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May 21st, 2014
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).
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.
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).
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.
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
May 4th, 2014
 Harrell’s Precision sells “semi-custom” full-length bushing dies for the PPC and 6BR chamberings. While the Harrell brothers do not cut the die to spec, they carry a large selection of dies made with slightly different internal dimensions. When you send in your fired brass, the Harrells choose a die from inventory with just the right amount of sizing (diameter reduction) at the top and bottom of the case. Given the quality, and precise fit, Harrell’s full-length dies are a good value at $75.00 plus shipping.
 Bump Measuring Collar
The Harrell brothers provide a nice bonus item with each full-length die — a neat, little shoulder bump measuring device as shown in the photo at right. Hornady/Stoney Point sells a stand-alone tool that does the same job, but the Harrell’s bump collar is simpler and faster. To measure your shoulder bump, simply place the Harrell’s bump collar over the upper section of your deprimed case (before sizing) and measure the OAL with your calipers. The collar should seat on the shoulder without any wobble. After taking the measurement, then size the case in your full-length die, replace the collar and repeat the measurement. You want to set your die so the shoulder moves back about .001″ to .0015″ for most applications. (With semi-auto guns you may want more bump — .003″ or more.)
When measuring for shoulder bump, you need to remove the primers first. Our friend Boyd Allen explains: “Use a decapping tool or die to remove the fired primer before taking the initial measurement. When working to thousandths, even the raised edge of a crater or a slightly raised primer can throw you off by a significant amount.”
May 3rd, 2014
 On German Salazar’s Rifleman’s Journal website, you’ll find an excellent 5-Part Series on barrel chambering. The Series, entitled The Voyeur’s Guide to Barrel Chambering, is not intended to be a “how-to” instructional treatise for gunsmiths. Instead, German’s 5-Part Guide is aimed at the end user — the shooter. German explains: “This Series isn’t intended for anyone who owns a lathe; instead it is for those of us who send an action off to get a new barrel installed. Those who have the equipment know what to do and how to do it and I have nothing to teach them. On the other hand, if you’ve ever wondered just what goes into barrel fitting, this is it.”
PART I | PART II | PART III | PART IV | PART V
With well-written text and dozens of very high-quality images, German takes you through the chambering, threading, shoulder-fitting, and crowning processes from start to finish. The idea is to give the “barrel consumer” a clear idea of the processes involved when a barrel blank is converted into functional form, complete with chamber, threaded tenon, fitted breech, and crown.
We highly recommend German’s 5-Part Voyeur’s Guide to Barrel Chambering. German, with the aid of John Lowther (who ran the machines), did a great job. The series has already drawn much attention from our Forum members, along with praise. After reading the articles, John C. from Australia wrote: “Your Chambering articles… really are excellent [and] informative for those of us too scared to watch our gunsmith chamber one of our barrels lest we distract him at a crucial moment!”
We know you’ll learn something from reading through German’s 5-Part Series. And if you see a photo on German’s website that intrigues you, simply click on it to see a larger, higher-resolution version. All the images in the Voyeur Series on RiflemansJournal.com can be zoomed to larger formats.
April 28th, 2014
Gunsmiths often have to serve as gun “doctors” as well as gun builders. Gunsmith (and Hall-of-Fame shooter) Thomas “Speedy” Gonzalez was recently asked to fix a trigger problem. A customer was complaining about a trigger that was erratic and “mushy”. Speedy quickly diagnosed the problem. The Jewell trigger was clogged with gunk and sludge — left-over solvents and lubricants had gummed up the mechanisms. Here’s how the cleaning process unfolded…
Speedy: “Gee why would I want to blueprint my Jewell trigger….it has just got a little mushy lately. It may just need some adjustment. Yeah right — take a look at this”:
Speedy: “Should I go get a tetanus shot now?”
Gunsmith Mike Bryant comments: “I’ve seen a lot of Remington 700 triggers that were gummed up like [that] Jewell was. Also have seen lots of 700 triggers that had the weight-of-pull screw adjusted [by the owner] to where it had no compression on the spring. I wonder how many of the Remington accidental discharges involved triggers with one or the other of these conditions.”
Speedy: “What?! Powder in trigger as well… hmmmmmm.”
Clean up done with Iosso Lubricant/Cleaner. Speedy says this is the “Best parts cleaner I have ever found if you don’t have an ultra sonic cleaning tank. I just melted that crud off with a Q-Tip”.
Same Jewell trigger all happy now — clean as a whistle.
Trigger ready for final re-assembly, looking better than new. Thanks Speedy!
April 19th, 2014
 At long range, small bullet holes are much easier to see in the white than in the black. When you’re practicing at long range on high power targets, one way to enhance your ability to see your bullet holes is to print a “negative” version of the regulation bullseye target.
How do you create a “negative” of a target image? Many image programs, including the FREE Irfanview software, have a “Negative” function in the pull-down menu. If you don’t see a “Negative” menu option in your program, look for a “substitute colors” option. Many printers also have a “reverse colors” function. If you can’t find a solution with your computer or printer, just take a normal bullseye target to a copy shop, and the staff can easily print you a set of targets with white centers in black fields.
Forum member Watercam uses a Pentax PF-80ED spotting scope. With his 80mm Pentax he can see 6mm bullet holes in the white at 600 yards (in very good conditions), but holes in the black are only visible out to 400 yards or so. Accordingly, Watercam uses a modified “reversed” black-to-white target for 600-yard practice.
Watercam told us: “The view through the Pentax is very sharp and contrasty with great color. Eye relief with the Pentax 10-60 power zoom is 18-22mm (much more than the Kowa zoom), so I can use glasses with no problem. With my 6mm and limited mirage I’m seeing defined, 6mm holes in the white out to 600. In the black, I can see bullets holes at about 400 with my eyes. I am printing reverse-color targets for training without a pit partner at the 600-yard line.”
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Brits Use New White-Field Target for F-Class
In the UK, ranges are now using a “reverse-style” target with a mostly white area. Laurie Holland says this allows shooters to see shots much more easily. Laurie reports: “Here’s a photo of the 500/600 yard F-Class match target we use in PSSA comps at Diggle Ranges with club members Chris Hull (L) and Terry Mann (R). We now use this target form at all ranges up to 1K for F-Class, and, yes you can often see your hits at 600 on the target before the markers pull it. Regards from England — Laurie”.
Day-Glo Stick-on Targets
If you’re not concerned with official scoring rings, you can use an all-white target with a bright, fluorescent target dot in the middle. A 2″- or 3″-diameter stick-on target dot is highly visible at 600 yards. With a high-quality scope, you can use the small black diamonds in the center for precise aiming. The Birchwood Casey Target Spots® assortment (item #33928-TSA) offers neon orange target dots in 1″, 2″, and 3″ diameters. This “value pack” includes 72-1″, 36-2″, and 24-3″ self-adhesive circles.
April 15th, 2014
When he chooses to measure his loads or sort bullets by weight, Forum Member Boyd Allen likes 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.”
April 11th, 2014
 The 2014 National Junior Olympic Shooting Championships (NJOSC) take place this month in Colorado Springs, Colorado. The prestigious event, which runs through April 26th, kicked off yesterday with air pistol matches.
Following the pistol competition, Women’s Rifle takes to the range April 16-20, and then the NJOSC will conclude with Men’s Rifle, April 22-26. Both rifle weeks will include both Air Rifle and Three-Position (smallbore) competition.
For the first time in the history of the National Junior Olympics, all competitors will shoot on electronic targets. USA Shooting completed a massive range upgrade to improve lighting and enhance the spectator experience by incorporating more than 70 new electronic targets. This is cutting-edge technology that allows both real-time scoring and even live video streaming on the internet. Shown below are the target print-outs for Air Pistol.
In our dreams we could hope for electronic scoring at high power and long-range centerfire events. Wouldn’t it be cool to have scores appear instantaneously, in real time? In addition, after firing a relay you could get a print-out that would show the exact placement of your shots in the scoring rings. That would be handy for analyzing your wind calls. But best of all, with electronic targets, shooters would no longer have to pull pit duty in the hot sun! Over time we may see more of this technology for centerfire competition. We’re told that the new 500-acre, $20 million CMP Talladega Marksmanship Park, being built in Alabama, will have some electronic scoring capabilities.
USA Shooting Video Streaming of Junior Olympics Events
On its YouTube channel, USA Shooting will provide Live and recorded events from the USA Shooting Olympic Training Center Ranges in Colorado Springs. As we write this, the NJOSC 2014 Men & Women Air Pistol Day 2 Air Pistol Relays are streaming. CLICK Here for NJOSC Videos and Streamed Events.
April 11th, 2014
This Article Originally Appeared in Sinclair International’s The Reloading Press.
Pre-Season Gun Maintenance,
by Ron Dague, Sinclair International
 I give my rifles a pre-season check before the shooting season starts. This starts with a general inspection starting with the butt-plate or recoil pad and making sure that all the screws and adjustable parts (on an adjustable butt-plate) move freely up or down and side to side. If you got caught in rain some of these screws and adjustable parts may not move when needed. I disassemble parts as needed and put rust preventative or a light oil and/or grease on threads and sliding parts. On rifles with recoil pads and fixed butt-plates, make sure the screws are tight and that holes in the stock aren’t stripped out. Make sure there are no cracks in the stock and around the butt-plate. If the recoil pad is glued-on, just make sure it hasn’t come loose.
Next I take the action out of the stock and check for cracks and wear marks. I look at the bedding to make sure that oils and cleaning solvents have not damaged the bedding. While the action is out of the stock, I look for any surface rust or dirt/dust in the recoil lug area and magazine well. Clean as needed and repair or re-bed if needed.
Trigger Assembly and Action
 With the barreled action out of the stock, it is a good time to spray out the trigger with cleaner. I use Ronson oil or lighter fluid. [Editor’s Note: Some trigger-makers advise against using any kind of lubricant, grease or oil — so plain lighter fluid is preferred.] After the trigger is cleaned you may want to check the trigger pull weight. If you don’t feel comfortable doing this, take it to a gun smith and have it checked. It is worth every penny to not have a trigger issue and/or a safety malfunction. I also take the bolt apart and clean the firing pin spring and bolt housing with Gun Scrubber or automotive brake cleaner. Then lube the firing pin-spring and firing pin with light oil. I use Kel Lube and/or Butch’s gun oil. Put a small dab of gun grease on the [bolt locking lugs] and cocking ramp.
I will also spray the outside of the action and barrel and give that a light coating of oil for rust prevention. I clean the action with Sinclair’s action cleaning tool. Don’t forget to clean the bore. Even though you didn’t fire the rifle, this makes sure nothing obstructs your barrel.
Checking Metal Fixtures and Fasteners
 Next I look at the trigger guard and hinged floor plate and make sure it works as designed. Make sure there are no cracks in the trigger guard from an accidental drop. Check guard screws and /or action screws for tightness and tighten to proper spec. There are torque specs for this, but on wood stocks the wood can crush and this should be checked throughout the year as weather change can affect this. My entire collection of rifles are bedded and I just tighten them just snug with screw driver or Allen wrench. The rimfire rifles have a spec of 55 to 74 inch/lbs and I think would carry over to center fire as well. I would caution you about torque wrenches as you need a good quality wrench, and read the directions on how to use it. You can over torque if not careful. Check the swivel studs and bipod to make sure there tight as well. You may want to take scope off and check the base screws and check the rings.
Test Fire the Rifle After Maintenance
After all cleaning and is done and everything is reassembled, take a few rounds out to the range and test fire to make sure everything works as it should. Don’t forget to run 3-5 rounds through the magazine at least two times for function. I look at this as preventive maintenance on the rifle. If you give it a look over you shouldn’t have any trouble during the rifle matches or hunting trip.
Ron Dague
Certified Reloading Instructor
Certified Range Safety Officer
Email: rond [at] sinclairintl.com
Phone: 800-717-8211
April 6th, 2014
As a cartridge case is reloaded multiple times, burnt powder residue and carbon builds up on the inside of the case. Unless the case interior is cleaned in some fashion, eventually you’ll see a reduction in case capacity. One of our Forum members from Australia wonders about the effects of reduced case capacity: “If the capacity of the case decreases as the crud builds up, then it effectively reduces the chamber size. Wouldn’t that change the pressure produced from that of an equivalent clean case?”
Ultrasonic Cleaning Example:
Interesting Test of Case Capacity Changes
Forum member Fred Bohl has actual test results that can help answer the above question. Fred proved that, over a 20-reload cycle, the case capacity of uncleaned cases did, indeed, decline a small amount. However, surprisingly, this did not seem to affect the actual chronographed velocity of the load. ES did increase, but Fred believes the higher ES was due to changes in case-neck tension, rather than due to the slight reduction in case capacity.
Fred reports: “Back when beginning to use ultrasonic case cleaning, part of the motivation was to get the inside clean based on the assumption that allowing burnt residue to build up inside cases would affect capacity, and, ultimately, performance. An experiment was done to test this hypothesis. The load used, 30.5 grains of RL15 behind 107gr SMKs in a 6mmBR, was selected for best group and lowest ES in prior load development. It turned out to be 92% of initial case capacity and neither “full” or compressed. (I would suspect that different powders, load weight, and total case capacity might produce very different results.)
We took 30 cases of identical initial capacity and tracked three lots of 10 each:
LOT 1: No Internal cleaning
LOT 2: Cleaned with media in tumbler
LOT 3: Cleaned with Ultrasound machine
Each case (in each lot) was shot and reloaded 20 times. The simplified results after 20 reloads of each lot were as follows:
Lot 1 (not cleaned) – 0.3 to 0.4 gr. loss of capacity, 5 to 8 fps greater ES.
Lot 2 (tumble cleaned) – 0.1 to 0.3 gr. loss of capacity, 4 to 6 fps greater ES.
Lot 1 (ultrasonic cleaned) – no loss of capacity, no detectable change in ES.
FINDINGS
There was no detectable correlation of velocity change to the lots. An oddity was that on very hot days Lot 1 velocities were, occasionally, slightly higher. [Editor’s note: That does suggest that the carbon build-up inside the uncleaned cases might cause a slight increase in pressure that shows up on hot days. Fred has posted that “A local shooter reported doing the 20 reload, no clean test on a .308 that gave a loss of capacity of 2.0 grains, doubled ES and signficant velocity changes. However, I don’t have any details on his load weight or powder.”]
NOTE: From results of another ongoing test, I believe the above differences in ES are probably due more to variance in bullet grip tension than case capacity. The ultrasound cleaned cases (LOT 3) did maintain the lowest ES, but we are not 100% sure of the reasons why. More consistent bullet seating might be the reason.
[Editor’s comment: Jason found that with his ultrasonically-cleaned cases, the inside of the necks got so “squeaky clean” that he needed to use dry lube in the necks. Jason uses the $10.95 dry lube kit from Neconos.com. This applies ultra-fine Moly powder to the neck using small carbon steel balls]
April 6th, 2014
by Bill Gravatt
(This article was written when Bill was President of Sinclair International, Inc.)
Chamber casting is an easy task for the handloader to perform. A chamber casting is valuable if you run across a firearm that you believe has a custom barrel on it and you want to find out the dimensions of the chamber. Some gunsmiths will chamber a barrel and not mark it properly with the neck dimension or the exact cartridge name or specifications. We also get calls from some customers that have military firearms without cartridge stampings on the barrel; this will help these shooters identify their chambering.
Another reason to make a chamber casting would be for a die manufacturer to manufacture custom dies for you. A chamber casting is often required when fired cases are not available. Some reloaders will make a chamber casting that shows them the exact configuration of the throat and leade so they can determine what bullets to try. Shooters using cast bullets will make a cast so they can choose a mould that better fits their throat taper and grove/lands diameter.
A product called Cerrosafe is the most common, reliable, and the safest material to use for making chamber castings. Cerrosafe is a metal alloy that has some unique properties which make it ideal for chamber casting. First, it has a relatively low melting point of 158 to 190° Fahrenheit. This makes it easy for the handloader to melt the Cerrosafe in his home shop. Second, it shrinks slightly during cooling which allows it to be extracted from the chamber easily. It then re-expands to the chamber’s original size after about one hour at room temperature. After cooling for about 200 hours, the chamber cast will expand to about .0025″ larger than the actual chamber size. Most good reloading die makers are used to working from Cerrosafe chamber casts.
As we said, using Cerrosafe is fairly easy and comes with complete instructions.
Making a Cerrosafe Chamber Cast — Step by Step:
1. First, clean and dry the chamber and barrel thoroughly.
2. Disassemble the firearm as necessary to gain access to the chamber.
3. Insert a tight fitting cleaning patch with a jag into the bore from the muzzle end to form a plug for the Cerrosafe. The patch should be positioned in the bore, just forward of the throat by approximately ½” to 1”.
4. Heat a Cerrosafe ingot in a small ladle. A heavy cast iron bullet caster’s ladle works fine or a plumber’s ladle. Any source of heat will do (a small propane torch will work fine).
5. Pour the Cerrosafe into the chamber until a little mound forms at the rear of the chamber. Too much and it can become more difficult to remove the cast from the chamber. If this happens, simply heat the barrel a little and re-melt the Cerrosafe. Don’t worry, your barrel gets a bit hotter than 190 degrees during firing.
6. The chamber can be difficult to access, so some people find it easier if they make a pouring tube out of steel, brass, or aluminum tubing to funnel the Cerrosafe into the chamber.
7. After the Cerrosafe has hardened, the chamber casting can be pushed out of the chamber coming from the muzzle end using a cleaning rod or a wooden dowel. It is recommended that you push it out within a half-hour of casting the chamber. We usually push our cast out within a few minutes. If the cast does not push out easily, insert a cleaning rod from the muzzle and tap the rod handle with the palm of your hand to start the cast out of the chamber. You can put a paper towel in the action to catch the cast or lay the rifle on the bench with a towel or bench mat underneath it to catch the cast as it falls from the action. This will prevent damage to the cast.
8. Take your measurements shortly after one hour of cast, and then put the casting away until you need it again. A medicine container or something similar makes a great container. If you are going to keep the cast be sure to mark the cast or the storage container so you know which rifle it came from. If you have no need to keep the cast you can re-melt the Cerrosafe and use it again when you need to make another cast. |
This article originally appeared in Sinclair International’s The Reloading Press Blog.
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