May 9th, 2017

High-Tech Honing — Major Advance in Barrel Making

Sunnen honing barrel hone CNC computer honer machine Pac-nor

Some custom barrel makers are now honing barrels (after drilling) to improve bore diameter uniformity, smooth the interior finish, and reduce barrel lapping times. For years, large-scale manufacturers of hammer-forged barrels have employed honing. Now the process is being used by smaller, “boutique” barrel-makers. This article explains how and why barrel honing is done. Take the time to watch the video. For anyone with an interest in barrel-making, this video is an eye-opener…

Barrel Honing Process Demonstrated (Worth Watching!):

Barrel Bore honing cut-rifled rifling hammer forging accurateshooter.com

For custom barrel makers, honing is a time-saver and cost cutter. A few minutes on a honing machine can cut lapping times in half, leaving a cross-hatched surface finish in single or low double-digit Ra. Honing is the same process used to make diesel fuel injectors with bore roundness and straightness controlled to fractions of a micron (<0.000040″), with surface finish Ra ≤0.15 µm (6 µin).

A key manufacturing process used for hammer-forged barrels is now getting attention from the makers of custom button-rifled barrels. This process is precision bore-honing. Honing produces a high-quality bore surface fast, which is critical to hammer forging. (Why is honing so important with hammer forging? Surface finish is the one feature of the barrel that cannot be controlled in hammer forging. Surface imperfections in a barrel blank tend to be amplified as the blank is formed on the rifling mandrel. And if the bore is chromed afterwards, imperfections in the surface finish become even more obvious.)

Honing dramatically improves bore diameter size uniformity and accuracy, surface finish and roundness throughout the length of the barrel. It can certainly be used in place of a pre-rifling lap. The chief difference between a lapped and honed bore is the direction of the finish lines in the bore. Honing leaves fine spiraling crosshatch lines, while a lap leaves lines going longitudinally in the bore. After rifling the manufacturer can remove the crosshatch finish with a quick lap if desired. Honing is fast, accurate, and can be automated. Its surface quality and geometry can duplicate lapping, except for the longitudinal lines of the lapped finish.

Frank Green of Bartlein Barrels told us: “We worked with Sunnen and we did all the initial testing on the prototype machine for them. The machine works great! We ordered and received last year a new manufactured machine with the changes we wanted on it and we just ordered a second one a month or so ago. Should be here next month.”

(more…)

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May 7th, 2017

Your Worst Nightmare: Catastrophic .338 Lapua Magnum Kaboom

Kaboom Manatee Savage .338 LM, Lapua Magnum, catastrophic, explosion, cleaning rod, obstruction
Click to zoom image

We first ran this story a couple years back. We’re republishing it today as a reminder to our readers that safety should be their paramount concern at the range. Avoid distractions and always check your barrel for obstructions before you chamber a round or pull the trigger. A moment of inattention can result in a catastrophic kaboom …

Discharging a .338 Lapua Magnum round with a cleaning rod in the barrel — that’s a recipe for disaster. What happens when a fired .338 caliber bullet and a cleaning rod try to occupy the same place at the same time? Well you get a catastrophic kaboom, with metal pieces flying all over the place, and a shooter very lucky to escape without serious injury. This incident occurred recently in Manatee, Florida, as reported by Sniper’s Hide member Queequeg. We thank SnipersHide.com for granting permission to publish these revealing images in the Daily Bulletin. CLICK HERE for more Kaboom info on the ‘Hide.

Kaboom Manatee Savage .338 LM, Lapua Magnum, catastrophic, explosion, cleaning rod, obstruction

This story should serve as a chilling reminder to follow proper safety practices whenever you are at the range. Always check to make sure there is no obstruction in the bore BEFORE loading a live round.

.338 Lapua Magnum + Cleaning Rod + Inattention = Kaboom!

Kaboom at Manatee!
Sniper’s Hide member Queequeg recently published shocking photos of a catastrophic kaboom involving a .338 Lapua Magnum (Savage action). The action was blown off the rifle, shrapnel went through the roof, and the barrel split at the tenon before taking an excursion downrange. The action did crack in the front but the lugs remained engaged so the bolt did not slam to the rear (luckily for the shooter).

Here’s the report: “This happened [January 20, 2014] at the Manatee Gun and Archery Club. Al, Ren and myself were there with a couple other folks. Ren was at bench 12, I was at 13. The fellow at 11 was running a Savage .338 Lapua. He had a very bad day! He damn sure could have killed himself and quite likely Ren as well.”

Kaboom Manatee Savage .338 LM, Lapua Magnum, catastrophic, explosion, cleaning rod, obstruction

Queeqeg added: “After the boom, I heard Ren ask ‘Are you alright’ and then turned to look in time to see the fellow reacting in total shock — literally stunned. Ren and I went over to him and could not see any major injuries. Ren was uninjured as well but had a lot of fiberglass splinters on him. The barrel nut is what I presume punched the two holes in the roof. The shooter is a regular there[.] He had been having a problem with sticky cases though he said he was certain the loads were mild. That’s why he was content to knock the sticky ones out with the rod. He simply forgot to remove the rod after knocking out the last stuck case. You can see what happened next.”

Kaboom Manatee Savage .338 LM, Lapua Magnum, catastrophic, explosion, cleaning rod, obstruction

Kaboom Manatee Savage .338 LM, Lapua Magnum, catastrophic, explosion, cleaning rod, obstruction

Kaboom Manatee Savage .338 LM, Lapua Magnum, catastrophic, explosion, cleaning rod, obstruction

Kaboom Manatee Savage .338 LM, Lapua Magnum, catastrophic, explosion, cleaning rod, obstruction

To learn more about this incident, go to the original Snipers Hide Forum Thread. There you’ll find more details and over four pages of related discussions.

The Important Lesson Here
What did the .338 LM shooter do wrong here? You will say — “Well that’s obvious, he left a cleaning rod in the barrel and then shot a round.” Yes, that was a potentially fatal error. But that was his second mistake — one that occurred only because he made a more fundamental judgment error first.

The FIRST mistake was not acknowledging the problem with his ammo. Had he heeded the warning signs, he would still have a rifle (and an unsoiled pair of trousers). When he first observed that he was having problems with extracting cases, a warning light should have gone off in his head. Presuming his extractor was not broken (and that the chamber was cut properly) he should have been able to extract his brass if he was running safe loads. The lesson here we all need to learn is that if you observe a serious ammo-related issue, it is time to stop shooting. Don’t try to invent work-arounds just to extend your range session, when there are clear signs that something is wrong, very wrong.

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May 5th, 2017

.22 LR Ammo Performance — ELEY Offers Online Lot Analyzer

ELEY Lot Analyzer online database

How good is .22 LR rimfire ammo you just bought? Well, until now, you had to just cross your fingers and do your own testing (unless you could make the journey to the Eley or Lapua test centers). Now that’s changed. In a matter of seconds, you can access tons of test data for Eley rimfire ammo, seeing how any given lot has performed, and how consistent it has proven. You can view a wealth of data, including group size, percentage of shots within tenths of inches from center, velocity and more. There’s even a 50-shot consolidated group display that conveniently reveals large sample accuracy in a glance. With ELEY’s new web-based Lot Analyzer, you can easily compare various lot numbers, choosing the one that shows the best test results.

ELEY Lot Analyzer online database

With the ELEY Lot Analyzer, simply enter any ELEY lot number into the online database. You’ll then see a heap of information including 10-Shot Groups, 50-Shot Groups, Average Velocity, Ballistics Coefficient, Shot Distribution graphs, and even the Eley Coin Test — the percentage of this lot capable of hitting a dime at 54.7 yards (50m). We believe the ELEY Lot Analyzer delivers the most comprehensive lot-specific ammo performance information ever provided by any ammunition manufacturer.

ELEY Lot Analyzer online database

ELEY is to be commended for making this information available. Shown below are some of the data views available for ELEY Force ammo Lot 3H16-30356:

ELEY Lot Analyzer online database

Try It Yourself with Lot Number 1016-02107
To see how the ELEY Lot Analyzer works first-hand, CLICK HERE and enter this lot number 1016-02107 (be sure to include the dash).

Lot Analyzer Data Available from 2015 Forward
We think the ELEY Lot Analzyer is great for the consumer. It is now possible to select a box of ammo from a store shelf, enter the ELEY lot number, and instantly see the performance of the ammunition. Get together with fellow shooters and compare your ELEY ammo. This service will be available for all ELEY lot numbers in the USA from 2015 forward. You can find the year of your ammunition by the third and fourth numbers in the lot. For example, if your lot number is 3016-30xxx, it is from the year 2016.

EDITOR’s NOTE — Test Center Performance vs. the Real World:
Our staff has tested rimfire ammo in both the ELEY and Lapua Test Centers, and then shot that same ammo later in competition at outdoor ranges. We learned something in the process. First, ammo can do well in a test tunnel, with a clamped test fixture, yet perform very differently outdoors on a real range. Likewise, ammo may shoot superbly in one rifle, yet perform so-so in another rifle, even when the barrels are from the same manufacturer.

We commend ELEY for providing the Lot Analyzer — this really does offer invaluable information to the consumer. This represents a big step forward. That said, you need to understand that factory test results cannot necessarily be duplicated in the real world. And we can confirm that some ammo which was less than stellar in the test tunnel actually shot superbly in real rimfire benchrest competition. LESSON: Even with the ELEY Lot Analyzer, you still need to do your own testing, with your own rifle, to verify .22 LR ammo performance.

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April 29th, 2017

Sinclair Int’l Offers 8-Part Series of Reloading Videos

free reloading videos sinclair international

Sinclair International has created a series of instructional videos illustrating the basics of metallic cartridge reloading. The 8-part series starts with reloading basics and provides step-by-step, how-to instructions that will help new reloaders get started. Detailed, animated illustrations show you what happens inside the chamber when shooting, and inside the dies during each step of reloading. The videos can be viewed on Sinclair Int’l’s YouTube page. Shown below is the first video in the series:

Each of the eight videos is hosted by Sinclair Int’l President Bill Gravatt. Bill doesn’t just show you “how”, he tells you “why”. The how-to segments cover case inspection, proper die set up, case sizing, primer installation, powder measuring, bullet seating, crimping, and even goes into the record keeping needed for the handloader. “We wanted to give shooters who haven’t reloaded a look at all the advantages of creating your own ammo and how easy it is to get started,” said Gravatt, “without telling them they had to have any certain brand or type of equipment to do the job.” The eight videos are:

Part 1 — Intro to Video Series
Part 2 — Intro to Reloading Safety
Part 3 — Metallic Cartridge Components
Part 4 — The Firing Sequence
Part 5 — Tools for Reloading
Part 6 — Loading Bottle-Neck Cartridges
Part 7 — Loading Straight Wall Cartridges
Part 8 — Reloading Series Conclusion

Reloading Tools
Shown below is Part 5 of the video series, covering the tools used for precision reloading.

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April 29th, 2017

Do-It-Yourself Adjustable Ammo Caddy (Under $10.00)

Flex Arm Flexible Port Level gooseneck Ammo Block caddy

Here’s a great Do-It-Yourself (DIY) project from Martin Tardif. Build your own height-adjustable ammo caddy for under ten bucks. This is a great project for F-Open competitors as well as anyone who shoots with a pedestal front rest, either on the ground or from a bench. The ammo caddy attaches, via a flexible arm, to your front rest. The flexy arm allows you to position your ammunition close to your rifle’s feeding port. That makes it easy to grab cartridges and load them into the chamber without shifting your shooting position. Nice job Martin!

Martin Explains How to Build the Ammo Caddy
Here are some pics of my DIY P.L.A.B. (Port Level Ammo Block). I cannibalized the goose neck from a Craftsman bendy-style utility light and bought a 3.5″x 1″ Acetal disk on eBay. I then drilled out the disk to accept twenty .284 Winchester rounds and screwed the disk to the bendy arm. The arm, by itself, wasn’t sturdy enough to support my fully loaded ammo block, so I inserted a 1/8″-diameter steel rod cut to length into the arm before I screwed it to the disk. On this Bald Eagle rest, I wasn’t using the windage adjustment cable. That allowed me to secure the bottom end of the arm to the unused 5/16″ x 18 bolt hole for the cable. [Editor’s Note: For other pedestal rest types/brands you may need to drill a hole for the base of the flexy arm.]

Flex Arm Flexible Port Level gooseneck Ammo Block caddy

Kudos to Martin Tardif for his clever use of inexpensive materials. The total cost of the whole project, according to Martin, was just $8.00!

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April 28th, 2017

Shot Costs Calculated for .223 Rem, 6BR, 6XC, .308 Win, 6.5×284

Shooting Cost by Cartridge Caliber type USAMU

Estimating Actual Cost per Round by Caliber
This article comes from the USAMU, which provide shooting and reloading tips on its Facebook Page. This week’s USAMU TECH TIP outlines a ballpark-estimate method of calculating the actual cost per round of different calibers. Some applications, and some shooters, by virtue of their high level of competition, require the very best ballistic performance available — “Darn the cost, full speed ahead!

If you are in serious contention to win a major competition, then losing even a single point to inferior ballistic performance could cost you a national title or record. However, this “horsepower” does come at a cost! Some calibers are barrel-burners, and some offer much longer barrel life. Look at this comparison chart:

Estimated Cost Per Round by Cartridge Type

Below are some estimated total expense per round (practice and competition) based on component costs, type used, expected barrel life and a standard, chambered barrel cost of $520.00 across calibers.

5.56x45mm: $0.46/round (barrel life 6,000 rounds)*

6mmBR: $0.81/round (barrel life 2800 rounds)

6XC: $0.97/round (barrel life 2200 rounds)

.308 Win: $0.80/round (barrel life 4500 rounds)

6.5-284: $1.24/round (barrel life 1100 rounds)

*Note the high round count estimate for 5.56x45mm. This is a bit deceptive, as it assumes a period of “lesser accuracy” use. The USAMU says: “Much of the difference you see here between 5.56 and .308 is due to using the 5.56 barrel for 100-200 yard training with less-expensive, 55gr Varmint bullets after its long-range utility is spent”.

Moreover, while some applications require specialized, high-cost components, others do not. And, if the shooter is still relatively new to the sport and hasn’t refined his skill to within the top few percentile of marksmen, a more economical caliber choice can help stretch a limited budget. Translation: More skill per dollar!

In this post, the prices for all items mentioned here were taken from a major component supplier’s current advertisements, and all brass was of top quality, except in the case of 5.56mm. There, 200 top-quality, imported cases were reserved for 600-yard shooting, and the other brass used was once-fired Lake City surplus.

Cartridge cases were assumed to be loaded 10 times each. [Your mileage may vary…] Bullet prices assumed the use of less-expensive, but good-quality match bullets for the bulk of shooting as appropriate.

The cost of top-tier, highly-expensive match bullets was also calculated for a realistic percentage of the shots fired, based on ones’ application. Barrel life by caliber was taken from likely estimates based on experience and good barrel maintenance.

Brass Costs Based on 10 Loads Per Case
Often, handloaders may calculate ammunition cost per round by adding the individual costs of primers, powder charges and projectiles. Many don’t consider the cost of brass, as it is reloaded several times. Here, we’ll consider the cost of enough top-quality brass to wear out a barrel in our given caliber, at 10 loads per case, except as noted above.

Don’t Forget Amortized Barrel Costs
Few shooters factor in the full, true cost of barrel life. Depending on caliber, that can dramatically increase the cost per round. For example, consider a long-range rifle in 6.5/284 caliber. This cartridge performs amazingly well, but at a cost. Ballpark estimated barrel life [in a top-quality barrel] is 1100 rounds. Some wear out faster, some last longer, but this gives a rough idea of what to expect.

Accurate barrels are a joy to use, but they are an expendable resource!
Shooting Cost by Cartridge Caliber type USAMU

A top-quality barrel plus installation was estimated at about $520.00. At 1100 rounds, barrel life adds $0.47 per round to our total cost. Thus, what had started out as an [components-only estimate, with brass cost] of $0.76/round now totals $1.24 per shot!

Cost Considerations When Choosing a Catridge Type
Some shooters might ask themselves if they could meet their present needs with a more economical caliber. If so, that equates to more practice and matches per available dollar, and more potential skill increase on the available budget.

Each shooter knows his skill level, practice needs, and shooting discipline’s requirements. Some might shoot NRA Service Rifle or Match Rifle using a 5.56mm with a long barrel life. Others might be Match Rifle shooters faced with choosing between, say, a 6mm BR vs. 6XC. A realistic assessment of ones needs, performance-wise, may help guide the shooter toward a caliber that’s most optimized to their needs at the moment.

Admittedly, the factors affecting cost for any individuals circumstances can vary significantly. However, hopefully this will provide one useful method of evaluating one’s training and competition choices, based on their skill, goals and needs.

USAMU reloading Facebook Page army tips tech

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April 25th, 2017

A Dozen Handy Items to Pack in Your Range Kit

Range Kit Gear shellholder safety dozen essentials

The shooting season is now in full swing. When you head to the range you’ll want to be prepared. That means collecting all the gear you’ll need at the range. It’s easy to forget small, critical items, so we’ve provided a checklist of the small “extras” you should pack before you head out to the range. In addition to rifle, rests, ammo, targets, and cleaning gear, here are a dozen essentials you should include in your range bag.

Shell-Holder — If you don’t have calipers, you can use a shell-holder to check for excessive case expansion from hot loads. If a fired case doesn’t slip into the shell-holder easily, your load is definitely TOO HOT.

Extra Earplugs — Always use ear protection when shooting. We bring a 35mm film canister with extra sets of foam earplugs.

Hex Wrench or Screwdriver for action screws — Action screws can work loose with time. Always bring the appropriate hex wrench or screwdriver whenever you go to the range.

Small Wrench for Scope Rings — Check the tension of your scope base and ring fasteners before you go. Bring along a small Torx wrench for the ring screws (or other tool that fits your fasteners).

Normal and Under-sized Jags — It is often wise to use one-caliber undersize jags when applying solvent with cotton patches. You should have a couple sizes in your range kit.

Extra Batteries — Bring extra batteries for all your electronic gear — which can include chronograph, windmeter, digital camera, GPS etc.

Small Notebook and Pen or Pencil — Use the notebook to record chron data, log group sizes, and make notes about wind and weather conditions.

Adhesive dots — Bring a few sheets of adhesive dots (sold at office supply stores). Use small white or black dots as target pasters. Use larger red or orange dots as aiming points (target centers).

Folding Chair or Camp Stool — This comes in handy if you’re spotting for another shooter, or if you reload away from the firing line.

Water Bottle — You can’t shoot well if you’re dehydrated. Bring at least two quarts of water with you and keep a bottle at the bench.

Surveyors’ Tape and Wood Stakes — You can make inexpensive wind indicators using surveyors’ tape attached to the top of wood stakes.

Small Plastic Ruler — Use this to measure your group sizes. A transparent (see-through) ruler works best. Rulers are also useful for drawing lines on targets.

This list is not intended to be exclusive. There are many other items you may wish to include. Obviously bring safety glasses, and Sharpie-type pens are always handy to mark targets. We invite our readers to add other “essentials” to the list. The important thing is to plan ahead, packing your key items before you drive to the range.

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April 25th, 2017

Zediker Book Helps with Build-You-Own AR-15 Projects

AR15 Varmint rifle AR gunsmithing robert whitley

AR15 construction guideMany of our readers use AR-type rifles for Service Rifle matches, varmint hunting, 3-Gun competition, or defensive use. AR-platform rifles can be configured in a multitude of ways to suit the application. But if you plan to put together your own purpose-built AR rifle, how do you get started?

For AR Do-It-Yourselfers, we suggest reading Glen Zedicker’s book, the Competitive AR-15 Builders Guide. Following on Zedicker’s New AR-15 Competitive Rifle book (2008), the Builders Guide provides step-by-step instructions that will help non-professional “home builders” assemble a competitive match or varmint rifle. This book isn’t for everyone — you need some basic gun assembly experience and an aptitude for tools. But the AR-15 Builders’ Guide provides a complete list of the tools you’ll need for the job, and Zedicker outlines all the procedures to build an AR-15 from start to finish.

One of our Forum members who purchased the AR-15 Builders Guide confirms it is a great resource: “Much like any of the books Mr. Zediker puts out this one is well thought-out and is a no nonsense approach to AR building. I can not stress how helpful this book is from beginner to expert level.”

Along with assembly methods, this book covers parts selection and preparation, not just hammers and pins. Creedmoor Sports explains: “Knowing how to get what you want, and be happy with the result, is truly the focus of this book. Doing it yourself gives you a huge advantage. The build will honestly have been done right, and you’ll know it! Little problems will have been fixed, function and performance enhancements will have been made, and the result is you’ll have a custom-grade rifle without paying custom-builder prices.” Creedmoor Sports sells this Zediker AR-15 book and many other excellent shooting books. Visit www.creedmoorsports.com/category/Books or call 1-800-CREEDMOOR.

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April 23rd, 2017

Polish Inside of Seating Stems to Avoid Ring Marks on Bullets

Seating Stem Reloading Tip Sierra Bullet .223 Remington compressed loads

Here’s a helpful hint for hand-loaders from Sierra Bullets. While this article focuses on Sierra’s new Tipped Match-King bullets, the recommended solutions apply to other bullet types as well. The article explains how sharp edges on a seating stem can cause a ring to be pressed into the bullet jacket — especially with compressed loads that resist downward bullet movement. Here Sierra technician Rich Machholz diagnoses the problem and provides a solution.

Seating Stem Reloading Tip Sierra Bullet .223 Remington compressed loads

Solutions for Ring Marks Caused by Seating Stems

by Sierra Bullets Ballistic Technician Rich Machholz
Now that the new Tipped MatchKing® (TMK) bullets are being shipped and shooters are putting them to use I have received several calls regarding marking on the bullet ogive from the seating stem.

The cause can be traced to one of several things. In the .223 and especially with the long, 77 grain TMK seated at 2.250” or even 2.260” most loads of Varget® and Reloder® 15 are compressed loads, sometimes heavily compressed. This puts a great deal of pressure on the bullet through the seating stem. The result of all this pressure is a mark of varying depth and appearance on the ogive of the bullet. [Editor: We have seen this issue with a variety of other bullet types/shapes as well, including non-tipped VLDs. The solution is profiling the internal cone of the seating stem to match your bullet shape.]

Some older seating stems might even bear against the tip of the bullet which can make a slight bulge in the jacket just below the junction of the resin tip and the copper jacket in a compressed load. If this is the case there is not a ready fix other than calling the die manufacturer and requesting a new deeper seating stem.

Polish Your Seating Stem to Remove Sharp Internal Edges
If the seating stem is of proper depth the culprit most generally is a thin sharp edge on the inside taper of the seating stem. This is an easy fix that can be accomplished by chucking a spare 77 grain bullet in your drill, coating it with valve grinding compound or even rubbing compound or in a pinch even tooth paste.* Remove the seating stem assembly from the seating die. Turn the drill on and put the seating stem recess over the spinning bullet with the polishing compound to break or smooth the sharp edge that is making the offending mark. This might take more than one application to get the proper polish depending upon what you use, but the more you polish the better the blend of angles which will [ensure the stem matches the bullet contours, not leaving a sharp ring].

If the above is a little more than you care to tackle you might try very fine emery cloth twisted to a point that can be inserted into the mouth to the seating stem and rotated to polish the inside to eliminate any sharp edges that might be present.

Load Advice for 77gr TMKs in the .223 Rem
And last but certainly not least. Actually, even though we don’t say you need additional data for the TMKs, remember you are dealing with heavily-compressed loads in some cases because of the additional bullet length. Due to the additional length of these new bullets and in the interest of gaining some room in the case you might consider trying a slightly faster extruded powder like BenchMark or the 4895s or an even more dense powder like the spherical H335®, CFE223 or TAC. The extra room will allow for trouble free bullet seating also.

Good luck and remember we are no further away than your telephone: 1-800-223-8799.

Sierra Bullets Match-King Reloading Bullet Seating

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April 22nd, 2017

When and How Scopes Fail — How to Diagnose Optics Problems

Riflescope Repairs

Riflescopes are mechanical contraptions. One of the sad realities about precision shooting is that, sooner or later, you will experience a scope failure. If you’re lucky it won’t happen in the middle of a National-level competition. And hopefully the failure will be dramatic and unmistakable so you won’t spend months trying to isolate the issue. Unfortunately, scope problems can be erratic or hard to diagnose. You may find yourself with unexplained flyers or a slight degradation of accuracy and you won’t know how to diagnose the problem. And when a 1/8th-MOA-click scope starts failing, it may be hard to recognize the fault immediately, because the POI change may be slight.

When An Expensive Scope Goes Bad
A few seasons back, this editor had a major-brand 8-25x50mm scope go bad. How did I know I had a problem? Well the first sign was a wild “drop-down” flyer at a 600-yard match. After shooting a two-target relay, I took a look at my targets. My first 5-shot group had five shots, fairly well centered, in about 2.2″. Pretty good. Everything was operating fine. Then I looked at the second target. My eye was drawn to four shots, all centered in the 10 Ring, measuring about 2.4″. But then I saw the fifth shot. It was a good 18″ low, straight down from the X. And I really mean straight down — if you drew a plumb line down from the center of the X, it would pass almost through the fifth shot.

Is My Scope Actually Malfunctioning or Is This Driver Error?
That was disconcerting, but since I had never had any trouble with this scope before, I assumed it was a load problem (too little powder?), or simple driver error (maybe I flinched or yanked the trigger?). Accordingly, I didn’t do anything about the scope, figuring the problem was me or the load.

Scope Failure mechanical Point of Impact

Even expensive scopes can fail, or start to perform erratically — and that can happen without warning, or for no apparent reason. Here are some signs that you may be having scope issues.

1. Click count has changed signficantly from established zero at known range.
2. Noticeably different click “feel” as you rotate turrets, or turrets feel wobbly.
3. Inability to set Adjustable Objective or side focus to get sharp target image.
4. Shot Point of Impact is completely different than click value after elevation/windage change. For example, when you dial 2 MOA “up” but you observe a 6 MOA rise in POI.

Problems Reappear — Huge POI Swings Affirm This Scope is Toast
But, at the next range session, things went downhill fast. In three shots, I did manage to get on steel at 600, with my normal come-up for that distance. Everything seemed fine. So then I switched to paper. We had a buddy in the pits with a walkie-talkie and he radioed that he couldn’t see any bullet holes in the paper after five shots. My spotter said he thought the bullets were impacting in the dirt, just below the paper. OK, I thought, we’ll add 3 MOA up (12 clicks), and that should raise POI 18″ and I should be on paper, near center. That didn’t work — now the bullets were impacting in the berm ABOVE the target frame. The POI had changed over 48″ (8 MOA). (And no I didn’t click too far — I clicked slowly, counting each click out loud as I adjusted the elevation.) OK, to compensate now I took off 8 clicks which should be 2 MOA or 12″. No joy. The POI dropped about 24″ (4 MOA) and the POI also moved moved 18″ right, to the edge of the target.

Riflescope RepairsFor the next 20 shots, we kept “chasing center” trying to get the gun zeroed at 600 yards. We never did. After burning a lot of ammo, we gave up. Before stowing the gun for the trip home, I dialed back to my 100-yard zero, which is my normal practice (it’s 47 clicks down from 600-yard zero). I immediately noticed that the “feel” of the elevation knob didn’t seem right. Even though I was pretty much in the center of my elevation (I have a +20 MOA scope mount), the clicks felt really tight — as they do when you’re at the very limit of travel. There was a lot of resistance in the clicks and they didn’t seem to move the right amount. And it seemed that I’d have four or five clicks that were “bunched up” with a lot of resistance, and then the next click would have almost no resistance and seem to jump. It’s hard to describe, but it was like winding a spring that erratically moved from tight to very loose.

At this point I announced to my shooting buddies: “I think the scope has taken a dump.” I let one buddy work the elevation knob a bit. “That feels weird,” he said: “the clicks aren’t consistent… first it doesn’t want to move, then the clicks jump too easily.”

Convinced that I had a real problem, the scope was packed up and shipped to the manufacturer. So, was I hallucinating? Was my problem really just driver error? I’ve heard plenty of stories about guys who sent scopes in for repair, only to receive their optics back with a terse note saying: “Scope passed inspection and function test 100%. No repairs needed”. So, was my scope really FUBAR? You bet it was. When the scope came back from the factory, the Repair Record stated that nearly all the internal mechanicals had been replaced or fixed: “Replaced Adjustment Elevation; Replaced Adjustment Windage; Reworked Erector System; Reworked Selector; Reworked Parallax Control.”

How to Diagnose Scope Problems
When you see your groups open up, there’s a very good chance this is due to poor wind-reading, or other “driver error”. But my experience showed me that sometimes scopes do go bad. When your accuracy degrades without any other reasonable explanation, the cause of the problem may well be your optics. Here are some of the “symptoms” of scope troubles:

1. Large shot-to-shot variance in Point of Impact with known accurate loads.
2. Uneven tracking (either vertical or horizontal).
3. Change of Point of Impact does not correspond to click inputs.
4. Inability to zero in reasonable number of shots.
5. Unexpected changes in needed click values (compared to previous come-ups).
6. Visible shift in reticle from center of view.
7. Changed “feel” or resistance when clicking; or uneven click-to-click “feel”.
8. Inability to set parallax to achieve sharpness.
9. Turrets or other controls feel wobbly or loose.
10. Internal scope components rattle when gun is moved.

Source of Problem Unknown, but I Have a Theory
Although my scope came with a slightly canted reticle from the factory, it had otherwise functioned without a hitch for many years. I was able to go back and forth between 100-yard zero and 600-yard zero with perfect repeatability for over five years. I had confidence in that scope. Why did it fail when it did? My theory is side-loading on the turrets. I used to carry the gun in a thick soft case. I recently switched to an aluminum-sided hard case that has pretty dense egg-crate foam inside. I noticed it took some effort to close the case, though it was more than big enough, width-wise, to hold the gun. My thinking is that the foam wasn’t compressing enough, resulting in a side-load on the windage turret when the case was clamped shut. This is just my best guess; it may not be the real source of the problem. Remember, as I explained in the beginning of this story, sometimes scopes — just like any mechanical system — simply stop working for no apparent reason.

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April 20th, 2017

New Spin on BC — How Barrel Twist Rates Affect Bullet Drag

Bryan Litz bullet rpm BC Drag ballistics coefficient twist rate

You may not realize it… but to get the optimum BC from your bullets (i.e. the lowest aerodynamic drag), you must spin the bullets fast enough. Bullet drag increases (as expressed by lower BC) if the bullet spins too slowly. Bryan Litz of Applied Ballistics explains how BC changes with twist rates…

More Spin, Less Drag
In this article, we look at how twist rate and stability affect the Ballistic Coefficient (BC) of a bullet. Again, this topic is covered in detail in the Modern Advancements book. Through our testing, we’ve learned that adequate spin-stabilization is important to achieving the best BC (and lowest drag). In other words, if you don’t spin your bullets fast enough (with sufficient twist rate), the BC of your bullets may be less than optimal. That means, in practical terms, that your bullets drop more quickly and deflect more in the wind (other factors being equal). Spin your bullets faster, and you can optimize your BC for best performance.

Any test that’s designed to study BC effects has to be carefully controlled in the sense that the variables are isolated. To this end, barrels were ordered from a single barrel smith, chambered and headspaced to the same rifle, with the only difference being the twist rate of the barrels. In this test, 3 pairs of barrels were used. In .224 caliber, 1:9” and 1:7” twist. In .243 caliber it was 1:10” and 1:8”, and in .30 caliber it was 1:12” and 1:10”. Other than the twist rates, each pair of barrels was identical in length, contour, and had similar round counts. Here is a barrel rack at the Applied Ballistics Lab:

Applied Ballistics used multiple barrels to study how twist rate affects BC.

stability gyroscopic ballistics coefficient drag twist rate

“The Modern Advancements series is basically a journal of the ongoing R&D efforts of the Applied Ballistics Laboratory. The goal of the series is to share what we’re learning about ballistics so others can benefit.” –Bryan Litz

Barrel twist rate along with velocity, atmospherics, and bullet design all combine to result in a Gyroscopic Stability Factor (SG). It’s the SG that actually correlates to BC. The testing revealed that if you get SG above 1.5, the BC may improve slightly with faster twist (higher SG), but it’s very difficult to see. However, BC drops off very quickly for SGs below 1.5. This can be seen in the figure below from Modern Advancements in Long Range Shooting.

The chart shows that when the Gyroscopic Stability Factor (SG) is above 1.5, BC is mostly constant. But if SG falls below 1.5, BC drops off dramatically.
stability gyroscopic ballistics coefficient drag twist rate

Note that the BC drops by about 3% for every 0.1 that SG falls below 1.5. The data supports a correlation coefficient of 0.87 for this relationship. That means the 3% per 0.1 unit of SG is an accurate trend, but isn’t necessarily exact for every scenario.

It’s a common assumption that if a shooter is seeing great groups and round holes, that he’s seeing the full potential BC of the bullets. These tests did not support that assumption. It’s quite common to shoot very tight groups and have round bullet holes while your BC is compromised by as much as 10% or more. This is probably the most practical and important take-away from this test.

To calculate the SG of your bullets in your rifle, visit the Berger Bullets online stability calculator. This FREE calculator will show you the SG of your bullets, as well as indicate if your BC will be compromised (and by how much) if the SG is below 1.5. With the stated twist rate of your barrel, if your selected bullet shows an SG of 1.5 (or less), the calculator will suggest alternate bullets that will fully stabilize in your rifle. This valuable online resource is based directly on live fire testing. You can use the SG Calculator for free on the web — you don’t need to download software.


Learn More About SG and BC
Barrel Twist Rate Velocity Modern Advancements Book Bryan Litz Applied BallisticsThis article is just a brief overview of the interrelated subjects of twist rate, Gyroscopic Stability, and BC. The coverage of twist rates in Modern Advancements in Long-Range Shooting is more detailed, with multiple live fire tests.

Other chapters in the book’s twist rate section include:
· Stability and Drag – Supersonic
· Stability and Drag – Transonic
· Spin Rate Decay
· Effect of Twist rate on Precision

Other sections of the book include: Modern Rifles, Scopes, and Bullets as well as Advancements in Predictive Modeling. This book is sold through the Applied Ballistics online store. Modern Advancements in Long Range Shooting is also available in eBook format in the Amazon Kindle store.

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April 13th, 2017

Digital Level Is Handy Tool for Your Range Kit

Here’s a cool product that can help you level your front rest and rear bag, level your scope, align your target frame, and perform a myriad of tasks around the house. The Digital AngleCube (aka Electronic Level and Protractor Gauge) is basically a high-tech level that gives you exact angular read-outs to within 0.2 degrees. That’s a lot more precise than any bubble level.

Numerous Shooting-Related Applications
For you position shooters who like to run angled sights, this tool will help you set the rear sight and front tower to exactly the same angle. For High Power guys with 3-way and 4-way adjustable buttstocks, this digital angle gauge can help you quickly and precisely set buttstock angle and cast-off. Even tactical shooters and long-range hunters can use this device to confirm exact shot angle, with greater precision than a plastic protractor or even an expensive Angle Degree Indicator (ADI). Heck you can even use the thing as an anti-cant device (if you don’t mind the extra weight). We’re sure that our clever readers can find even more uses for a digital angle read-out tool.

The AngleCube Digital Level sells on Amazon.com for $29.95. It comes with magnets on the sides so you can attach the tool to any ferrous metal surface for a “hands-free” reading. You can find similar devices in hardware and home improvement stores. One of these square, magnet-equipped electronic protractor/levels is made by INSIZE. The illustration below shows how the INSIZE gauge can be used in the field.

Story Sourced by Edlongrange.
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April 9th, 2017

Don’t Kill the Chrono! Setting up Chronos to Avoid Stray Shots

chronograph placement, shooting chrony, chrono, advisory, tech tip

Each year we repeat this story as a caution to readers using conventional chronographs set up on tripods downrange. There is nothing more frustrating (or embarassing) than sending a live round into your expensive new chronograph. As the photo below demonstrates, with most types of chronographs (other than the barrel-hung Magnetospeed), you can fatally injure your expensive chrono if it is not positioned precisely.

When setting up a chrono, we always unload the rifle, remove the bolt and bore-sight to ensure that the path of the bullet is not too low. When bore-sighting visually, set up the rifle securely on the sandbags and look through the bore, breech to muzzle, lining up the barrel with your aim point on the target. Then (during an appropriate cease-fire), walk behind the chronograph. Looking straight back through the “V” formed by the sky-screens, you should be able to see light at the end of the barrel if the gun is positioned correctly. You can also use an in-chamber, laser bore-sighter to confirm the visual boresighting (see photo).

Laser boresighter chronograph

Adjust the height, angle and horizontal position of the chronograph so the bullet will pass through the middle of the “V” below the plastic diffusers, no less than 5″ above the light sensors. We put tape on the front sky-screen supports to make it easier to determine the right height over the light sensors.

Use a Test Backer to Confirm Your Bullet Trajectory
You can put tape on the support rods about 6″ up from the unit. This helps you judge the correct vertical height when setting up your rifle on the bags. Another trick is to hang a sheet of paper from the rear skyscreen and then use a laser boresighter to shine a dot on the paper (with the gun planted steady front and rear). This should give you a good idea (within an inch or so) of the bullet’s actual flight path through the “V” over the light sensors. Of course, when using a laser, never look directly at the laser! Instead shine the laser away from you and see where it appears on the paper.

chronograph set-up

Alignment of Chronograph Housing
Make sure the chrono housing is parallel to the path of the bullet. Don’t worry if the unit is not parallel to the ground surface. What you want is the bullet to pass over both front and rear sensors at the same height. Don’t try to set the chrono height in reference to the lens of your scope–as it sits 1″ to 2″ above your bore axis. To avoid muzzle blast interference, set your chronograph at least 10 feet from the end of the muzzle (or the distance recommended by the manufacturer).

chronograph laser sky screens

Rifles with Elevated Iron Sights
All too often rookie AR15 shooters forget that AR sights are positioned roughly 2.4″ above the bore axis (at the top of the front sight blade). If you set your bullet pass-through point using your AR’s front sight, the bullet will actually be traveling 2.4″ lower as it goes through the chrono. That’s why we recommend bore-sighting and setting the bullet travel point about 5-8″ above the base of the sky-screen support shafts. (Or the vertical distance the chronograph maker otherwise recommends). NOTE: You can make the same mistake on a scoped rifle if the scope is set on very tall rings, so the center of the cross-hairs is much higher than the bore axis line.

Laser boresighter chronograph

TARGET AIM POINT: When doing chrono work, we suggest you shoot at a single aiming point no more than 2″ in diameter (on your target paper). Use that aiming point when aligning your chrono with your rifle’s bore. If you use a 2″ bright orange dot, you should be able to see that through the bore at 100 yards. Using a single 2″ target reduces the chance of a screen hit as you shift points of aim. If you shoot at multiple target dots, place them in a vertical line, and bore sight on the lowest dot. Always set your chron height to set safe clearance for the LOWEST target dot, and then work upwards only.

Other Chronograph Tips from Forum Members:

When using a chronograph, I put a strip of masking tape across the far end of the skyscreens about two-thirds of the way up. This gives me a good aiming or bore-sighting reference that’s well away from the pricey bits. I learned that one the hard way. — German Salazar

A very easy and simple tool to help you set up the chronograph is a simple piece of string! Set your gun (unloaded of course) on the rest and sight your target. Tie one end of the string to the rear scope ring or mount, then pull the string along the barrel to simulate the bullet path. With the string showing the bullet’s path, you can then easily set the chronograph’s placement left/right, and up/down. This will also let you set the chrono’s tilt angle and orientation so the sensors are correctly aligned with the bullet path. — Wayne Shaw

If shooting over a chrono from the prone position off a bipod or similar, beware of the muzzle sinking as recoil causes the front of the rifle to drop. I “killed” my first chronograph shooting off a gravel covered firing point where I’d not given enough clearance to start with and an inch or two drop in the muzzle caused a bullet to clip the housing. — Laurie Holland

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April 9th, 2017

Tech Tip: Always Check Headspace with New Barrels

A friend of ours recently took delivery of a new barrel which was chambered by a smith who had done the original build on the rifle, but who had not headspaced the barrel on the action itself this time. The smith headspaced based on his old records. Our friend happily screwed on his nice, new barrel and headed to the range. After the first few rounds, with known, safe loads, he was seeing deep craters on his primers, and then he even pierced a few primers with loads that should never have done that. Interestingly, the brass was not showing any of the other pressure signs. This was with bullets seated .015″ out of the rifling.

We were thinking maybe too much firing pin extrusion or maybe he got a hot lot of powder. Then I asked him to email me dimensions off his fired cases compared to new, Lapua brass. He emailed me that his shoulder moved 0.0105″ forward. I sent an email back saying, “hey, that must be a typo, you meant 0.0015″ right — so your shoulder moved one and a half thousandths correct?” The answer was “No, the shoulder moved over TEN thousandths forward”. Ahah. This explained some of the cratering problem in his brass. His cases were able to bounce forward enough in the chamber so that the primer material was smearing over the firing pin. And now he has brass that is “semi-improved”.

go no-go field headspace gauges

The point of the story is always check your headspace when you receive a “pre-fit” barrel, even from the smith who built the rifle. Purchase Go/No Go gauges for all your calibers. Headspace is not just an accuracy issue, it can be a safety issue. Pierced primers are bad news. The debris from the primer cup can blow into the firing pin hole or ejector recess causing a myriad of problems.

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April 7th, 2017

Wind Wizardry — How to Use a Kestrel Correctly

Kestrel Wind Meter Direction Vane Applied Ballistics

A lot of folks use a Kestrel Wind Meter every time at the range. That’s a good thing. However, many Kestrel owners may not be employing the Kestrel properly when seeking wind direction.

A Kestrel Wind Meter will record wind speed with its impeller wheel. However, to get the most accurate wind velocity reading, you need to have your Kestrel properly aligned with the wind direction. To find wind direction, first orient the Kestrel so that the impeller runs at minimal speed (or stops), and only then turn the BACK of the Kestrel into the wind direction. Do NOT simply rotate the Kestrel’s back panel looking for the highest wind speed reading — that’s not the correct method for finding wind direction. Rotate the side of the Kestrel into the wind first, aiming for minimal impeller movement. The correct procedure is explained below by the experts at Applied Ballistics.

How to Find the Wind Direction with a Kestrel Wind Meter

Here is the correct way to determine wind direction with a Kestrel wind meter when you have no environmental aids — no other tools than a Kestrel. (NOTE: To determine wind direction, a mounted Wind Vane is the most effective tool, but you can also look at flags, blowing grass, or even the lanyard on your Kestrel).

Step 1: Find the wind’s general direction.

Step 2: Rotate the Wind Meter 90 degrees, so that the wind is impacting the side (and not the back) of the wind meter, while still being able to see the impeller.

Step 3: Fine-tune the direction until the impeller drastically slows, or comes to a complete stop (a complete stop is preferred). If the impeller won’t come to a complete stop, find the direction which has the lowest impact on the impeller.

Step 4: Turn the BACK of the Kestrel towards the direction from which the wind is blowing. Then press the capture button, and record your wind speed.

Do NOT simply point the Kestrel’s back into the wind until you get the highest wind speed — that’s not the correct method.

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April 6th, 2017

Going Big (.338 and Beyond) — Big Bore Basics with Bryan Litz

Big Bore Bryan Litz Applied Ballistics .416 Barrett .376 CheyTac .408 CheyTac .50 BMG BC Solid Bullets

In this video Bryan Litz of Applied Ballistics offers tips on Big Bore shooting (i.e. .338 caliber and above). Bryan offers advice on bullet selection and he explains the challenge of handling the blast, noise, concussion, and recoil of big boomers such as the .416 Barrett and .50 BMG.

Bryan goes big … very big, shooting a monster .50 BMG bullpup.
Watch the recoil pulse shove Bryan backwards at 1:40 time-mark:

Big Bore Basics — Tips for Shooting Big Boomers by Bryan Litz
There are some unique things to consider with big-bore shooting. One is bullet design. For long-range shooting you want high-BC bullets. You get high BC from heavy bullets and bullets that have low drag. The interesting trade-off in big calibers is that there are a lot more lathe-turned solid bullets in copper and brass available than there are in the smaller calibers. You’ve got bullets that have slightly lower drag profiles but they are made of materials that are slightly less dense (than lead) so they are relatively light for their caliber. With that trade-off, the BCs might not be as high as you think for big calibers, although the bullets are heavy enough that they carry a lot of energy.

Energy really has a lot to do with shooting these big-caliber rifles. As with any kind of shooting, the fundamentals of marksmanship are the most important thing. However, it can be hard to maintain good fundamentals (e.g. trigger control and sight alignment) when you’re burning 100 grains of powder. There’s a lot of concussion (you want a muzzle brake no matter what your cartridge is above .338). It certainly can be challenging with all the muzzle blast and all the energy coming out of the barrel.

For long-range shooting with big bore rifles, you are still looking for the same things that you want with smaller-caliber rigs. You want a high-performance bullet, you want consistent ammunition, and you want a good fire solution to be able to center your group at long range. Basically you’re just dealing with the challenges that the high energy brings, and being smart about your bullet selection.

Big Bore Bryan Litz Applied Ballistics .416 Barrett .376 CheyTac .408 CheyTac .50 BMG BC Solid Bullets

In the video above, Bryan is shooting the DesertTech HTI bullpup. This rifle can shoot four (4) big bore chamberings, with barrel conversion kits for: .375 CheyTac, .408 CheyTac, .416 Barrett, and .50 BMG. These can be quickly swapped in the HTI chassis, which employs an internal barrel-clamp system.

Big Bore Bryan Litz Applied Ballistics .416 Barrett .376 CheyTac .408 CheyTac .50 BMG BC Solid Bullets

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April 5th, 2017

TECH Tip: Video Shows How to Hydro-Form Cartridge Brass

6mm Dasher hydroforming case die hornday

Can you form a wildcat cartridge such as the 6 Dasher without expending primer, powders, and bullets? Absolutely. Using the hydro-forming method you can form improved cases in your workshop with no firing whatsoever, so there is no wear on your precious barrel. Watch this video to see how it’s done:

6 Dasher Case Hydro-Forming Demonstration:

Forum member Wes J. (aka P1ZombieKiller) has produced a helpful video showing how to form Dasher cases use the Hornady Hydraulic forming die kit. This includes a two-part die (body and piston), and a special shell holder. To form the case, you insert a primer in your virgin brass, top the case off with with a fluid (water or alcohol), then run the case up into the Hydro-forming die. A few stout whacks with a hammer and your case is 95% formed.

6mm Dasher hydroforming hydraulic 6mmBR hornadyHydro-Forming Procedure Step-by-Step:
1. Insert spent primer in new 6mmBR brass case.
2. Fill with water or alcohol (Wes prefers alcohol).
3. Wipe excess fluid off case.
4. Place case in special Hornady shell-holder (no primer hole).
5. Run case up into Hydraulic forming die.
6. Smack top piston of forming die 3-4 times with rubber mallet or dead-blow hammer.
7. Inspect case, re-fill and repeat if necessary.
8. Drain alcohol (or water) into container.
9. Remove primer (and save for re-use).
10. Blow-dry formed case. Inspect and measure formed case.

Wes achieves very uniform cartridge OALs with this method. He measured ten (10) hydro-formed 6 Dasher cases and got these results: two @ 1.536″; 2 @ 1.537″; and 6 @ 1.538″.

Three or Four Whacks Produces a 95%-Formed Case
With a Hornady hydro-forming die, hydraulic pressure does the job of blowing out the shoulders of your improved case. The process is relatively simple. Place a spent primer in the bottom of a new piece of brass. Fill the case with water, and then slip it into a special Hornady shell-holder with no hole in the middle. Then you run the case up into the forming die. Now comes the fun part. You gently insert a plunger (hydraulic ram) from the top, and give it three or four stiff whacks with a mallet (or better yet, a dead-blow hammer). Remove the plunger and you have a 95% formed case, ready to load.

Walter Queen Hydraulic Hornady DieHornady supplies a shell holder made specifically for the hydro die; there’s no hole in the bottom of it. Just insert a spent primer into the primer pocket and you’re ready to go. The spent primer combined with the solid shell holder, keeps the water from seeping out of the primer pocket. The primer pushes out a little bit during this process, but it’s impossible for it to come out because of the way the shell holder is designed. The shell holder has a grove which allows the case to slide out of the shell holder even when the primer protrudes a bit.

Story tip from Boyd Allen. We welcome reader submissions.

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March 26th, 2017

Five Great Tech Articles: Bedding, Target Software, Case Prep, Action Torque, Stock Painting

Technical Article AccurateShooter OnTarget, Stock painting, Pillar Bedding

AccurateShooter.comReaders who have just recently discovered the Daily Bulletin may not realize that AccurateShooter.com has hundreds of reference articles in our archives. These authoritative articles are divided into mutiple categories, so you can easily view stories by topic (such as competition, tactical, rimfire, optics, shooting skills etc.). One of the most popular categories is our Technical Articles Collection. On a handy index page (with thumbnails for every story), you’ll find over 100 articles covering technical and gunsmithing topics. These articles can help you with major projects (such as stock painting), and they can also help you build more accurate ammo. Here are five popular selections from our Technical Articles archive.

pillar Bedding

Stress-Free Pillar Bedding.
Richard Franklin explains how to do a top-quality bedding job, start to finish.

On Target Software Review

OnTarget Software Review.
Our Editors test free software that measures shot groups with great precision. We explain how to use the program and configure advanced features.

Savage Action Tuning Torque Settings

Savage Action Tuning.
Top F-TR shooter Stan Pate explains how to enhance the performance of your Savage rifle by optimizing the torque settings of the action screws.

Precision Case Prep for Reloading

Complete Precision Case Prep.
Jake Gottfredson covers the complete case prep process, including brass weight sorting, case trimming, primer pocket uniforming, neck-sizing, and, case-neck turning.

rifle stock painting and spraying

Stock Painting Instructions.
Step-by-step guide for stock painting by expert Mike Ricklefs. Mike shows both simple coverage and fancy effects.

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March 24th, 2017

Verify Your TRUE Scope Click Values with Tall Target Test

Scope Click Verify Elevation Tall Target Bryan Litz NSSF test turret MOA MIL

Have you recently purchased a new scope? Then you should verify the actual click value of the turrets before you use the optic in competition (or on a long-range hunt). While a scope may have listed click values of 1/4-MOA, 1/8-MOA or 0.1 Mils, the reality may be slightly different. Many scopes have actual click values that are slightly higher or lower than the value claimed by the manufacturer. The small variance adds up when you click through a wide range of elevation.

In this video, Bryan Litz of Applied Ballistics shows how to verify your true click values using a “Tall Target Test”. The idea is to start at the bottom end of a vertical line, and then click up 30 MOA or so. Multiply the number of clicked MOA by 1.047 to get the claimed value in inches. For example, at 100 yards, 30 MOA is exactly 31.41 inches. Then measure the difference in your actual point of impact. If, for example, your point of impact is 33 inches, then you are getting more than the stated MOA with each click (assuming the target is positioned at exactly 100 yards).

Scope Click Verify Elevation Tall Target Bryan Litz NSSF test turret MOA MIL

How to Perform the Tall Target Test
The objective of the tall target test is to insure that your scope is giving you the proper amount of adjustment. For example, when you dial 30 MOA, are you really getting 30 MOA, or are you getting 28.5 or 31.2 MOA? The only way to be sure is to verify, don’t take it for granted! Knowing your scopes true click values insures that you can accurately apply a ballistic solution. In fact, many perceived inaccuracies of long range ballistics solutions are actually caused by the scopes not applying the intended adjustment. In order to verify your scope’s true movement and calculate a correction factor, follow the steps in the Tall Target Worksheet. This worksheet takes you thru the ‘calibration process’ including measuring true range to target and actual POI shift for a given scope adjustment. The goal is to calculate a correction factor that you can apply to a ballistic solution which accounts for the tracking error of your scope. For example, if you find your scope moves 7% more than it should, then you have to apply 7% less than the ballistic solution calls for to hit your target.


CLICK HERE to DOWNLOAD Tall Target Worksheet (PDF)

NOTE: When doing this test, don’t go for the maximum possible elevation. You don’t want to max out the elevation knob, running it to the top stop. Bryan Litz explains: “It’s good to avoid the extremes of adjustment when doing the tall target test.I don’t know how much different the clicks would be at the edges, but they’re not the same.”

Should You Perform a WIDE Target Test Too?
What about testing your windage clicks the same way, with a WIDE target test? Bryan Litz says that’s not really necessary: “The wide target test isn’t as important for a couple reasons. First, you typically don’t dial nearly as much wind as you do elevation. Second, your dialed windage is a guess to begin with; a moving average that’s different for every shot. Whereas you stand to gain a lot by nailing vertical down to the click, the same is not true of windage. If there’s a 5% error in your scope’s windage tracking, you’d never know it.”

Scope Tall Test level calibrationVerifying Scope Level With Tall Target Test
Bryan says: “While setting up your Tall Target Test, you should also verify that your scope level is mounted and aligned properly. This is critical to insuring that you’ll have a long range horizontal zero when you dial on a bunch of elevation for long range shots. This is a requirement for all kinds of long range shooting. Without a properly-mounted scope level (verified on a Tall Target), you really can’t guarantee your horizontal zero at long range.”

NOTE: For ‘known-distance’ competition, this is the only mandatory part of the tall target test, since slight variations in elevation click-values are not that important once you’re centered “on target” at a known distance.

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March 22nd, 2017

Chronograph Testing — Tips from the USAMU

USAMU Marksmanship Unit Velocity Chronograph Testing Sample Sizes

Each Wednesday, the U.S. Army Marksmanship Unit publishes a reloading “how-to” article on the USAMU Facebook page. This past week’s “Handloading Hump Day” article, the latest in a 7-part series, relates to chronograph testing and statistical samples. We highly recommend you read this article, which offers some important tips that can benefit any hand-loader. Visit the USAMU Facebook page next Wednesday for the next installment.

Chronograph Testing — Set-Up, Sample Sizes, and Velocity Factors

Initial Chronograph Setup
A chronograph is an instrument designed to measure bullet velocity. Typically, the bullet casts a shadow as it passes over two electronic sensors placed a given distance apart. The first screen is the “start” screen, and it triggers an internal, high-speed counter. As the bullet passes the second, or “stop” screen, the counter is stopped. Then, appropriate math of time vs. distance traveled reveals the bullet’s velocity. Most home chronographs use either 2- or 4-foot spacing between sensors. Longer spacing can add some accuracy to the system, but with high-quality chronographs, 4-foot spacing is certainly adequate.

Laboratory chronographs usually have six feet or more between sensors. Depending upon the make and model of ones chronograph, it should come with instructions on how far the “start” screen should be placed from one’s muzzle. Other details include adequate light (indoors or outdoors), light diffusers over the sensors as needed, and protecting the start screen from blast and debris such as shotgun wads, etc. When assembling a sky-screen system, the spacing between sensors must be extremely accurate to allow correct velocity readings.

Statistics: Group Sizes, Distances and Sample Sizes
How many groups should we fire, and how many shots per group? These questions are matters of judgment, to a degree. First, to best assess how ones ammunition will perform in competition, it should be test-fired at the actual distance for which it will be used. [That means] 600-yard or 1000-yard ammo should be tested at 600 and 1000 yards, respectively, if possible. It is possible to work up very accurate ammunition at 100 or 200 yards that does not perform well as ranges increase. Sometimes, a change in powder type can correct this and produce a load that really shines at longer range.

The number of shots fired per group should be realistic for the course of fire. That is, if one will be firing 10-shot strings in competition then final accuracy testing, at least, should involve 10-shot strings. These will reflect the rifles’ true capability. Knowing this will help the shooter better decide in competition whether a shot requires a sight adjustment, or if it merely struck within the normal accuracy radius of his rifle.

How many groups are needed for a valid test? Here, much depends on the precision with which one can gather the accuracy data. If shooting from a machine rest in good weather conditions, two or three 10-shot groups at full distance may be very adequate. If it’s windy, the rifle or ammunition are marginal, or the shooter is not confident in his ability to consistently fire every shot accurately, then a few more groups may give a better picture of the rifle’s true average.

(more…)

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