April 22nd, 2021

Bet You Ain’t Seen This Before — Barrel-Indexing Rimfire Action

Bill Myers Indexing Action

The late Bill Myers was recognized as one of greatest rimfire gunsmiths who ever lived. Myers crafted many match-winning, record-setting rimfire benchrest rigs. Here we feature one of Bill’s most interesting creations — a clamping action that allows a rimfire barrel to be indexed (rotated) around the bore axis.

Bill was a creative thinker, and his own exhaustive testing has convinced him that barrel indexing can enhance accuracy in rimfire benchrest guns. Myers did acknowledge that, particularly with a very good barrel, the advantages of indexing may be subtle, and extensive testing may be required. Nonetheless, Myers believed that indexing could improve rimfire accuracy.

Indexing with the Myers’ Clamping Action
To index the barrel, Myers simply loosens the three clamping-bolts and rotates the barrel in the action. Because there is no thread to pull the barrel in or out, the headspace stays the same no matter how much the barrel is rotated. In other words you can rotate the barrel to any position on the clockface and the headspace remains unchanged.

Bill Myers Indexing Action
Bill Myers Indexing Action

The Challenge of Barrel Indexing
cone breech bill myers rimfire indexable actionWith a conventional barrel installation, employing a shoulder with a threaded tenon, it is difficult to index the barrel. Even with a cone breech (photo right) that eliminates the problem of extractor cuts, you’d have to use shims to alter the barrel index position, or otherwise re-set the shoulder each time you screwed the barrel in further.

Clamping Action Allows Barrel to Be Rotated to Any Position
Bill has come up with a masterful solution to barrel indexing. He designed and built his own prototype custom action that clamps the barrel rather than holding it with threads. The front section of the action is sliced lengthways, and then clamped down with three bolts. A special bushing (the gold-color piece in photos) fits between the barrel and the action. By using bushings of different inside diameters, Bill can fit any barrel up to an inch or so diameter, so long as it has a straight contour at the breech end. To mount the barrel, Bill simply places the fitted bushing over the barrel end-shank, then slips the “sleeved” barrel into the front end of the action. Tighten three bolts, and the barrel is secure.

Bill Myers Indexing Action

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April 22nd, 2021

BYOB — Build Your Own Barricade for PRS/NRL Practice

6.5 Guys Ed Mobley Steve Lawrence

Here’s a great Do-It-Yourself project for tactical shooters. Ed and Steve of the 65Guys.com have created a versatile wooden barricade designed for easy transport. The goal with this design was to create a stable barricade that offers a variety of shooting positions, but can also fit in the bed of a pick-up or the back of an SUV. The 69″ tall barricade is hinged in the middle, so it’s just 27″ wide. To deploy the Barricade you simply fold it open and then nest the lower wings in ground-level stands.

We call this the BYOB Project — Build Your Own Barricade. Anyone with basic wood-working skills should find the Barricade prettyeasy to make. The only tricky part is cutting the side Dado joints for the left and right lower wings. But when you’ve got it completed, you have a low-cost unit that is versatile and sturdy yet easy to pack in a truck and carry out on the range. In the video below the 6.5 Guys showcase their Gen 2 barricade and explain how to build one just like it.

Looking at the 6.5 Guys Modular Barricade
The Modular Barricade was drawn up by Steve in PowerPoint and then dimensions added. Once the entire plan was created, Steve cut components to size and then used ordinary wood screws and wood glue to assemble the barricade frame. This was done to ensure maximum rigidity due to the light weight construction using 2″ x 2″ frame members. A long piano hinge was used to allow the Barricade to fold in half, while still having high torsional rigidity. Each of the Barricade openings are 12″ x 12″ square. This consistent ‘window’ spacing allows interchangeable panels with different cut-out shapes to be placed at varies heights/locations in the Barricade.

Modular Barricade Key Features
— Lightweight construction using low-cost 2×2 wood beams.
— Collapsible frame with center hinges for easy transport and deployment.
— Multiple Support levels at 6″ vertical intervals (6″ variance R to L).
— Modular port design allows ports to be changed and moved as desired.

6.5 Guys Ed Mobley Steve Lawrence


CLICK HERE to Download 6.5 Guys Barricade Plans PDF »

6.5 Guys’ Modular Barricade — Construction Tips
The Modular Barricade can be constructed over a weekend with the proper materials and basic shop tools such as a power saw and electric screwdriver. Steve used a router for the side panel dado joints but a table saw could also be used for that task. Steve’s only real issue with the build involved the port panels — getting them to fit right. The 2″ x 2″ frame wood wasn’t always straight; even a small variation in the wood could cause a port panel to be too tight or too loose. Steve had to do a lot of extra sanding and planing to get the port panels to fit just right.

Where and How to Use the Barricade for Training
Because the 6.5 Guys’ Modular Barricade is so easy to move, you can simply pack it up and deploy it at your local range for practice. (Do ensure club/range rules allow shooting from barricades.) While the Barricade is designed to sit on the natural ground, the base stands can also be placed on concrete if your range does not allow deployment forward of the normal firing line. While you can use the Barricade for training on your own, Ed and Steve say novice shooters can benefit from a formal clinic.

In the video below, the 6.5 Guys discuss precision rifle training with Scott Satterlee, an instructor with Core Shooting Solutions. This video explains why new shooters should consider enrolling in a formal training clinic. Topics covered are: typical course format and “curriculum”, the gear needed to participate in a precision rifle clinic, and skills shooters should practice before attending the clinic.

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April 22nd, 2021

AR, Garand, M1A — Six Rules for Semi-Auto Gas Gun Reloading

Reloading for Service Rifles
SFC Lance Dement as featured in CMP’s First Shot Online.

The U.S. Army Marksmanship Unit (USAMU) has published a great series of reloading “how-to” articles on its Facebook Page. This post covers key factors to consider when loading ammunition for Match Rifles and Service Rifles, with a particular focus on self-loading “gas guns”. Visit the USAMU Facebook Page each Wednesday for other, helpful “Handloading Hump-Day” tips.

We offer some “cardinal rules” to help new gas-gun handloaders with safety and efficiency. These address both Match Rifle and Service Rifle versions of the AR15, M1 Garand, M1A, and M110. However, they can also improve safe reloading for many other auto-loaders such as M1 Carbines, FALs, SIGs, etc. The author distilled these principles many years ago to help focus on the essential aspects of these rifles.

RULE ONE: Service Rifles Are Not Benchrest Rifles
Gas-guns require a relatively loose fit between ammunition and chamber (vs. bolt actions) for safe, smooth operation. Many techniques, such as neck sizing and keeping cartridge headspace quite tight, are popular in the extreme bolt gun accuracy realm. However, they are of little value with Service Rifles, and some could even be hazardous. Before adopting a specialized technique, seriously consider whether it is appropriate and beneficial in a gas-gun.

RULE TWO: Never Compromise Safety to Obtain Accuracy
Example: If choosing a brand of great, but ultra-sensitive match primers offers possibly better accuracy at the risk of slam-fires in your design of rifle, don’t do it! You are issued exactly two eyes and ten fingers (best-case scenario). Risking them trying to squeeze 0.25 MOA better accuracy out of an M1A, etc. simply isn’t worth it.

Reloading for Service Rifles

RULE THREE: Tailor the Precision to Your Individual Skill and Your Rifle’s Potential
This has been addressed here before, but bears repeating for newcomers. If you are struggling to break out of the Marksman Class, or using a CMP M1 “As-Issued,” then laboriously turning the necks of your 600-yard brass is a waste of time. Your scores will improve much faster by practicing or dry-firing. On the other hand, if the reigning champions anxiously check your scores each time you fire an event, a little neck-turning might not be so far-fetched.

Verifying Load Improvements — Accuracy hand-loading involves a wide variety of techniques, ranging from basic to rather precise. Carefully select those which offer a good return on investment for your time and labor. In doubt? Do a classic pilot study. Prepare ammo for at least three or four ten-shot groups with your new technique, vs. the same with your standard ammo. Then, pick a calm day and test the ammo as carefully as possible at its full distance (e.g. 200, 300, or 600 yards) to verify a significant improvement. A little testing can save much labor!

RULE FOUR: Be Your Own Efficiency Expert
Serious Service Rifle shooters generally think of ammunition in terms of thousands of rounds, not “boxes”, or even “hundreds”. Analyze, and WRITE DOWN each step in your reloading process. Count the number of times each case is handled. Then, see if any operations can be dropped or changed without reducing safety or accuracy. Eliminating just two operations saves 2000 steps per 1000 rounds loaded. Conversely, carefully consider any measurable benefits before adding a step to your routine.

RULE FIVE: In Searching for Greater Accuracy with Efficiency, Look for System Changes
For example, instead of marking your 300-yard rounds individually to differentiate them from your 200-yard ammo, would a simple change in primers work? If accuracy is maintained, using brass-colored primers for 200 and silver for 300 provides an indelible indicator and eliminates a step! Similarly, rather than spending hours selecting GI surplus brass for weight and neck uniformity, consider splurging on some known, high-quality imported match brass for your 600-yard loads. Results should be excellent, time is saved, and given limited shooting at 600 yards, brass life should be long.

RULE SIX: Check All Your Primers Before Packaging Your Loaded Ammo
This seems simple and even intuitive. However, many slam-fires (which were much more common when M1s and M1As were the standard) are due, at least in part, to “high” primers. Primers should be seated below flush with the case head. The USAMU has addressed this at length in a previous column, but each round should be checked for properly-seated primers before they are packaged for use.

Reloading for Service Rifles

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