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September 3rd, 2009
When developing a load for a new rifle, one can easily get consumed by all the potential variables — load weight, seating depth, neck tension, primer options, neck lube, and so on. When you’re fully focused on loading variables, and the results on the target are disappointing, you may quickly assume you need to change your load. But we learned that sometimes the load is just fine — the problem is the trigger puller, or the set-up on the bench.
Here’s an example. We were recently testing two new Savage F-Class rifles, both chambered in 6mmBR. Initial results were promising, but not great — one gun’s owner was getting round groups with shots distributed at 10 o’clock, 2 o’clock, 5 o’clock, 8 o’clock, and none were touching. We could have concluded that load was no good. But then, another shooter sat down behind the rifle and put the next two shots, identical load, through the same hole. Shooter #2 had his own issues with the bag and rest and eventually produced a 6-shot group that was a vertical line, with 2 shots in each hole but at three different points of impact. OK, now we can conclude the load needs to be tuned to get rid of the vertical. Right? Wrong. Shooter #3 sat down behind the gun and produced a group that was pretty much a horizontal line with almost no vertical. Hmmm… what gives?
Well each of the three shooters had a different way of holding the gun and adjusting the rear bag. Shooter #1, the gun’s owner, used a wrap-around hold with hand and cheek pressure, and he was squeezing the bag. All that contact was moving the shot up, down, left and right. Shooter #2 was using no cheek pressure, and very slight thumb pressure behind the tang, but he was experimenting with different bag positions. His hold eliminated the side push, but variances in bag position and down pressure caused the vertical string. When he kept things constant, the gun put successive shots through the same hole. Shooter #3 was using fairly heavy cheek pressure. This settled the gun down vertically, but it also side-loaded the rifle. The result was almost no vertical, but a lot of horizontal.
A “Second Opinion” Is Useful
Conclusion? Before you spend all day fiddling with a load, you might want to adjust your shooting style and see if that affects the group size and shape on the target. Additionally, it is nearly always useful to have another experienced shooter try your rifle. In our test session, each time we changed “drivers”, the way the shots grouped on the target changed significantly. We went from a big round group, to vertical string, to horizontal string. Interestingly, all three shooters were able to diagnose problems in their shooting styles, and then refine their gun-handling. As a result, in a second session, we all shot that gun better, and the average group size dropped from 0.5-0.6 inches into the threes.
That’s right, we cut group size in half, and we didn’t alter the load one bit. Switching shooters demonstrated that the load was good and the gun was good. The skill of the trigger-puller(s) proved to be the limiting factor in terms of group size.
August 5th, 2009
RELOADING TIP: Andris Silins has come up with a simple way to measure length to the lands in your rifle:
“Here’s what I did to find length to lands for seating my bullets. I made four cuts into the neck of fire-formed brass. Then I pressed the bullet in lightly and chambered the entire gauge. As the cartridge chambers, the bullet slides back into the case to give you length to lands. It took less than five minutes to get it cut and working. A little light oil in the barrel just past the chamber helps ensure the bullet does not get stuck in the lands. It works great and is very accurate.
I made the cuts using a Dremel with a cut-off wheel. You can adjust tension two ways. First, you can make the cuts longer or shorter. Longer cuts = less tension. If you used only three cuts insted of four you would get more tension. The trick is to be gentle when you open and close the bolt. If you ram the bolt closed you may wedge the bullet into the lands. When you open the bolt it helps to keep a finger or two near by to guide the case out straight because the ejector wants to push it sideways.”
July 21st, 2009
Benchrest shooter Bill Gammon offers a nice product that helps prevent solvents and oils from marring the finish of a fine wood stock, or a painted fiberglass stock. The STOKBOOT also prevents solvents from softening the bedding, while guarding against nicks and scratches. Gammon’s STOKBOOT fits over the rifle stock during cleaning of the barrel. The quilt on the outside soaks up the solvent before it reaches the stock and holds it until it evaporates. A twin layer of vinyl on the inside stops any solvents from getting through, but Gammon cautions that you should not leave the STOKBOOT on overnight, because solvents could soak through. The basic colors are Red, Wine, Black, Blue, and Green. Typical retail price is about $16.00.
Gammon explains how he came up with the STOKBOOT: “My wife Barbara and I started this business in 1992 as a means to support a very expensive sport, namely Bench Rest. My wife had been in the sewing business for many years. Her experience included sewing, layout, cutting, and management, so it was only logical that the next step was opening our own business. I had complained about having to use a rag over my stock to prevent solvents that I was using from ruining the paint job on the stock, and also seeping into the bedding area and softening up the bedding. So between her expertise in the sewing world and my practical knowledge, we came up with our first STOKBOOT.”
Currently, Gammon offers wholesale orders. His STOKBOOTs are available through popular shooting sports vendors including: Borden Rifles, Kinneman’s Products, Russ Haydon’s Shooters’ Supply, Sinclair International. European dealers are Reloading Solutions for the UK, and Heinz Henke Online in Germany.
July 11th, 2009
One of our writers is shooting in the SoCal Precision Rifle Competition (SCPRC) match this weekend. When assembling his gear for this tactical match we realized there was a problem. He needed to carry 10 rounds “at the ready”, but his rifle lacked detachable magazines. He didn’t want to depend on ammo stored in a backpack or carried in a belt caddy. To quickly access the ammo on his belt or in his pack he would have to get up out of firing position. Our challenge was to figure out the most efficient way to stow 10 rounds on the gun itself.
Elastic Ammo Sleeves
To secure the needed 10 rounds on the gun, we looked at a variety of options. First we tried some slide-on elastic sleeves. These were cheap ($4-$6), but the elastic sleeve tended to slide forward on the buttstock, and as it moved forward it could also rotate. Plus these elastic sleeves held only 9 rounds max. One too few. Shown in the photos are the $4.99 Cabela’s 8-round “Bullet Band” and the Allen 9-round ammo carrier ($3.49 on sale at MidwayUSA). Yes our writer could carry an extra round in his pocket, but we figured there was a better solution.
8-Round Eagle Ammo Carrier
Next we looked at the Eagle Industries Gunstock Ammo Carrier. With THREE velcro-secured straps, including one around the back, this holder was secure. It didn’t slide forward or rotate on the butt-stock. However it cost $28.00 locally, and it only held 8 rounds. Too much money for too little capacity….
Plastic Ammo Caddy Solution — 10 Rounds, Zero Dollars
We then came up with a very simple solution. Federal ammunition comes in sturdy, TEN-round plastic ammo caddies that protect the bullet tips. The caddies have plastic loops at either end so that you can carry the unit on a belt (or other strap). These cartridge-holders cost nothing — people toss them into the trash at ranges.
 Using strapping tape — one strand through the loops on the backside, and another layer over the top — we had our “field expedient” 10-round ammo carrier for an all-up cost of $0.00. Zip. Nada. (Duct-tape works as well, but the strapping tape is a cleaner install. See photo right.)
Ugly? Yes — but hey, it works.
Another option with the plastic caddy is body-mounting. Using the belt loops, you can sew the cartridge-holder to an elastic (fabric) arm brace and just slip it on your forearm. That gives you a 10-round, easy-access ammo carrier for under $5.00.
Gunstock Ammunition Carrier (Plus Plastic Caddy in Pocket)
OK, even if it IS a cheap, functional solution, some of you guys will NEVER duct-tape a plastic cartridge holder to your $4500.00 tactical wondergun. It’s just not… how shall we say… “Tacti-Cool”. We know that some Tac shooters are acutely image-conscious. For them it would be a major fashion faux pas to duct-tape an ammo caddy to an Accuracy Int’l or GAP Crusader.
If you don’t mind dropping $40.00 or so, there is a solution that gives you a proper tactical set-up, PLUS 15 rounds on the rifle. This, ultimately, is what our writer chose. He purchased an Eagle Industries Stock Pack ($39.09). This features a padded, suede cheekpad, and secure elastic straps at the rear and bottom. Our writer now can mount five (5) rounds on the outside of the pack. In addition, he carries ten (10) more rounds on his Federal plastic cartridge holder, stowed in the Stock Pack’s zippered pocket.
July 5th, 2009
When he chooses to measure his loads or sort bullets by weight, Forum Member Boyd Allen likes to use his trusty RCBS 10-10 scale. He finds that it works predictably, time after time, and it doesn’t suffer from the drift and calibration issues that plague some of the less expensive electronic scales on the market.
To make it easier to see the balance point, Boyd has adapted a magnifying glass with a mirror. This makes the end of his balance beam easier to view from his normal position on the bench. Boyd explains: “This set-up uses a cheap magnifier with positioning arms that was probably designed to hold and magnify small objects while soldering them. I think that it came from Harbor Freight many years ago. The mirror lets you look at the scale as if is was at eye level, and of course the magnifier makes the image easier to see.”
May 28th, 2009
Three-gun match competitor Zak Smith employs a simple, handy means to store his elevation and wind dift data — a laminated data card. To make one, first generate a come-up table, using one of the free online ballistics programs such as JBM Ballistics. You can also put the information in an Excel spreadsheet or MS Word table and print it out. You want to keep it pretty small.
Below is a sample of a data card. For each distance, the card includes drop in inches, drop in MOA, drop in mils. It also shows drift for a 10-mph cross wind, expressed three ways–inches, MOA, and mils. Zak explained that “to save space… I printed data every 50 yards. For an actual data-card, I recommend printing data every 20 or 25 yards.” But Zak also advised that you’ll want to customize the card format to keep things simple: “The sample card has multiple sets of data to be more universal. But if you make your own data card, you can reduce the chance of a mistake by keeping it simple. Because I use scopes with MILS, my own card (bottom photo) just has three items: range, wind, drop in MILS only.”
Once you have the card you can fold it in half and then have it laminated at a local office store or Kinko’s. You can keep this in your pocket, tape it to your stock, or tie the laminated card to your rifle. If you regularly shoot at both low and high elevations, you may want to create multiple cards (since your ballistics change with altitude). To learn more about ballistic tables and data cards, check out the excellent “Practical Long-Range Rifle Shooting–Part 1″ article on Zak’s website. This article offers many other insights as well–including valuable tips on caliber and rifle selection.
Another option is to place your ballistics card on the back of the front flip-up scope cover. This set-up is used by Forum member Greg C. (aka “Rem40X”). With your ‘come-up’ table on the flip-up cover you can check your windage and elevation easily without having to move up off the rifle and roll the gun over to look at the side of the stock. Greg tells us: “Placing my trajectory table on the front scope cover has worked well for me for a couple of years and thought I’d share. It’s in plain view and not under my armpit. And the table is far enough away that my aging eyes can read it easily. To apply, just use clear tape on the front objective cover.”
May 18th, 2009
 Mark your calendars for Wednesday, May 20th, when a “must-watch” episode of ShootingUSA television is broadcast. On the 20th, Sergeant Grant Singley and other members of the USAMU Service Rifle Team explain wind-reading for long range competition. This should be a very informative segment, enhanced with on-screen graphics illustrating key points.
Sgt. Singley notes: “A 5-mph crosswind at 600 yards will move an 80gr .223 bullet about 15 inches. You can see that being able to accurately read the wind will greatly enhance your success on the rifle range.” The USAMU uses a clock method to estimate wind value based on the direction. Then you add in the measured (or estimated) velocity for the vector value (wind strength and angle).
Sgt. Singley recommends the use of a wind meter, such as a Kestrel, to gauge wind speed. But observed conditions will also indicate wind velocity. Sgt. Singley explains: “Zero-to-three mph, is hardly felt on the shooters face, but smoke will drift. Three-to-five mph is felt lightly on the shooter’s face. Five-to-eight mph keeps leaves in constant movement. Eight-to-12 mph will blow dust and loose paper, and 12-to-15 mph winds cause small trees to sway.”
Using Mirage to Estimate Wind Speed and Direction
Long-range shooters also need to learn how to read mirage. Mirage is the reflection of light through layers of air that have a different temperature than the ground. These layers are blown through by the wind, and can be monitored through a spotting scope, to detect direction and speed. You can see what appear to be waves running across the screen. This is the mirage. The waves appear to be running right to left, which indicates a wind coming out of the right. To clearly see the mirage through a spotting scope, you bring the target into focus, then adjust the focus about a quarter turn counter-clockwise.”
Graphics copyright 2009 ShootingUSA, used with permission.
April 27th, 2009
 We’ve learned that many first-time visitors to AccurateShooter.com may come in via a link to the Daily Bulletin rather than through our home page. As a result, they may not be aware that there is a wealth of other content available to our readers. Our Shooters’ Forum, with nearly 8,000 registered members, is one of the best places on the web to discuss precision shooting and advanced reloading. We also offer FREE Forum Classifieds. On the editorial side, AccurateShooter.com offers hundreds of pages of content, with thousands of photos. Our Cartridge Guides are considered definitive sources of tech info for popular match calibers, and our Guns of the Week articles provide in-depth reports on outstanding custom rifles, most of which have competition pedigrees. In addition, we offer videos, gear reviews, book reviews, an event calendar, and even FREE downloadable targets.
If you’re a new visitor to AccurateShooter.com, you should check out all that we have to offer. There are hundreds of informative articles to read … and they’re all free.
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April 25th, 2009
 Ever wondered what twist rate is required to stabilize a particular bullet? Or would you like to see how changes in spin rates (rpm) affect bullet stability? Well thanks to our friends from Canada, you’ll find helpful formulas online that answer many questions about external ballistics.
The Ballistics Page for the Canadian National Firearms Association (NFA) website offers a variety of useful programs and data charts created by Peter Cronhelm. These include:
Caliber Twist Rate Chart
Greenhill Formula Twist Calculator
Bullet Stability Calculator (requires MS Excel)
Ballistic Coefficients Chart (MS Word), (Or DOWNLOAD HERE.)
Ranging Ballistics Computer (Scroll to bottom of page.)
This exterior ballistics computer works in conjunction with range data as well as computing a conventional drop and windage chart. Using an FFP (Final Firing Point) and multiple TRP’s (Target Reference Points) the system will simultaneously calculate Drop and Windage data for up to 30 TRP’s 360 degrees around the FFP. Windage is corrected for the TRP direction compared to the primary wind direction. The spreadsheet consists of six individual pages. Each page performs a distinct function and contains all the information required to complete a shot at a target or targets. The entire system can be used in any laptop or handheld computer capable of running MS Excel or Excel CE.
CLICK HERE to download Ranging Ballistics Computer (requires MS Excel)
Rimfire Ammo Comparison Table
Canada’s NFA even provides a detailed table with bullet weights and velocities for over 100 varieties of 22LR Rimfire ammunition from Aguila, CCI, Eley, Federal, Fiocchi, Lapua, PMC, Remington, RWS, and Winchester. This Rimfire Ammo Table is a “must-have” resource for any smallbore shooter. Shown below is the section for Lapua:
April 9th, 2009
Now through April 30, 2009, MidwayUSA has the Hornady (formerly Stoney Point) Lock-N-Load Overall Length Gauge (item 570611) on sale for $25.99. That’s $4.50 off the regular price. Note, in addition to the Gauge itself, you’ll need a threaded modified case for each caliber you shoot, and we recommend having a comparator body with caliber-specific insert. The comparator allows you to measure from base of case to bullet ogive (rather than bullet tip).
OAL Gauge shown with Comparator to allow measurement from bullet ogive.
This Editor personally uses the Hornady Overall Length Gauge to find the distance to the lands for all his centerfire rifles. With practice, using the right technique, you can achieve measurements that are very repeatable. Here’s my method:
1. After screwing the modified case securely to the gauge, insert the case (with a bullet in neck) into the chamber. Make sure the modified (threaded) case goes ALL the way into the chamber. (Note: a heavily-fouled chamber can interfere with the seating of the modified case.)
2. Slide the gray pusher rod gently forward until you feel the first, slight resistance, then stop.
3. Now with the tip of your finger, tap the gray rod gently two or three times. This should give you a good, repeatable bullet contact with the lands, without going into the rifling.
4. You do NOT want to push hard on the gray rod. This will cause the bullet to engage the rifling. That will cause the bullet to stick, and you will end up with inconsistent length-to-lands measurements.
Some folks complain that this tool is not particularly repeatable. Well, if you use and practice the technique above, I think you’ll find the opposite is true. Using the Hornady OAL Gauge with a Berger bullet in a 6PPC, I recently measured length to lands five times in a row, with a couple witnesses to the procedure. Each of the measurements was consistent within .0007″ as recorded with a set of Mitutoyo Digital calipers. The key is using the same technique and pressure every time. CLICK HERE for a complete review of the Hornady OAL Gauge, with many photos
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