AR-platform rifles are fun and versatile, but the standard, mil-spec triggers leave much to be desired. They tend to be gritty, with creep and heavy pull weight. One of the easiest, most effective AR upgrades is a trigger group swap. An improved fire control group makes a huge difference. There are many aftermarket trigger options for the AR platform rifles. Choose single-stage or two-stage, either standard trigger assembly or unitized “drop-in” trigger, such as those made by Timney or Triggertech.
When upgraded with a precision trigger and match barrel, AR-platform rigs work great in NRA High Power competitions (Photo from NRA Blog, at Camp Perry).
Two-Stage vs. Single-Stage Triggers
Two-stage triggers have two separate movements. The first stage offers a light, spring-loaded pressure that works against the shooter’s pull until stopping at the second stage – this is called “take-up”. If there is no spring pressure, it is known as “slack”. Should the shooter continue to pull the trigger once he’s arrived at the second stage, the mechanism will operate like a single-stage trigger from there until engaging the sear and firing the gun. Good trigger reset requires the shooter to keep pressure on the trigger, even during reset, to minimize movement of the muzzle.
Single-stage triggers feature no take-up or slack, as they begin engaging the sear as soon as the shooter begins pulling the trigger. Some competitive shooters prefer the two-stage trigger because of the feedback it provides during its first stage, while other shooters, including those using their rifle in tactical scenarios, may want the surety of a single-stage trigger, ready to engage and fire once their finger is inside the trigger guard. Regardless of preference, a good trigger will feature minimal creep and should be free of grittiness, providing a smooth, even break.
Drop-In Trigger Assembly vs. Standard Trigger Group
Once you decide between a single-stage or two-stage trigger, you can choose between standard and drop-in trigger groups. Standard trigger groups feature all the fire control group parts separated, and need to be pieced together and installed much like a mil-spec trigger, while drop-in trigger are pre-assembled and contained within a casing that simply drops in to the receiver and accepts the pins, hence the name.
After-Market Trigger Comparison
Some shooters prefer drop-in triggers due to the ease of installation, while others opt for standard groups so they can access the components individually for cleaning adjustment or replacement. If one piece of a drop-in trigger fails, you’ll need to either replace the entire unit or send it to the manufacturer for repair, whereas you may be able to simply replace the broken component of a standard trigger without needing a whole new trigger set.
Trigger Terminology — “Creep”, “Stacking”, “Overtravel”
“Creep” or “travel” is the distance the trigger moves between the end of take-up and when the trigger breaks to fire the fun. Too much creep can affect accuracy, but no creep can be unsafe, as the shooter may not be prepared to fire. “Stacking” occurs when the trigger weight actually increases during travel — this shouldn’t happen. Lastly, “overtravel” is the distance the trigger continues moving back after the gun fires.
This article is based on a longer story in the NRA Blog.
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Craters may look interesting on the moon, but you don’t want to see them on your primers. Certain mechanical issues that cause primer craters can also cause primer piercing — a serious safety problem that needs to be addressed. If you have a gun that is cratering primers (even at moderate pressure levels), there is a solution that works with many rifles — send your bolt to Greg Tannel to have the firing pin hole bushed.
Shooters who convert factory actions to run 6BRs, 6PPCs or other high-pressure cartridges should consider having the firing pin bushed. These modern cartridges like to run at high pressures. When running stout loads, you can get cratering caused by primer flow around the firing pin hole in the bolt face. The reason is a little complicated, but basically the larger the hole, the less hydraulic pressure is required to crater the primer. A limited amount of cratering is normally not a big issue, but you can reduce the problem significantly by having a smith fit a bushing in the firing pin hole. In addition to reduced cratering, bushing the firing pin often produces more consistent ignition.
This is a highly recommended procedure that our editors have had done to their own rifles. Greg Tannel (Gre-Tan Rifles) is an expert at this procedure, and he does excellent work on a wide variety of bolts. Current price for a bushing job, which includes turning the firing pin to .062″, is $80.00, or $88.00 with USPS Priority Mail return shipping.
If you have a factory rifle, a bushed firing pin is the way to go if you are shooting the high-pressure cartridges such as 6PPC, 6BR, 6-6.5×47 and 6.5×47. This is one of the most cost-effective and beneficial upgrades you can do to your factory rifle. For more info on the Firing Pin Bushing process, visit GreTanRifles.com, or email greg [at] gretanrifles.com. (After clicking the link for GreTanRifles.com, Click on “Services” > “Shop Services” > “Bolt Work”, and you’ll see a listing for “Bush Firing Pin Hole & Turn Pin”. Select “View Details”.)
Firing Pin Hole Bushing by Greg Tannel
Work Done: Bush firing pin hole and turn pin.
Functions: Fixes your cratering and piercing problems.
Price: $80.00 + $8.00 return shipping Total Price: $88.00
Actions for which Bushing is Offered: Remington, Winchester, Savage multi-piece pin, Sako, Kimber, Nesika, Stiller, BAT Machine, Kelbly, Lawton, Surgeon, Borden, Wichita, Hall, Ruger, Howa, Weatherby, Dakota, Pacific Tool, Phoenix, and Defiant bolt action rifle or pistol.
Actions for which Bushing is NOT Available: Case hardened receivers, ARs, Accuracy International (AI), Barnard, Big Horn, Cooper, Desert Tactical Arms, Kimber, Rosenthal, New Savage single piece pin, Rimfires, Falling block, Break-open, Lever, Pump rifles, 1903-A3, CZ, Mauser.
How to send your bolt in to be bushed:
You can send your bolt snail mail, priority mail, or UPS (Please do not use FEDEX as it sometimes has delivery delays). Pack your bolt carefully and ship to: Gre’-Tan Rifles, 24005 Hwy. 13, Rifle CO 81650. Please include your name, phone number, and return shipping address.
Due to the high volume of work, turn around is 5 to 8 weeks on bushing a bolt. Three or more bolts will be sent back to you UPS and we will have to calculate shipping. We can overnight them at your expense. You can pay by check, money order, or credit card. For more information visit GretanRifles.com.
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How is a modern, metal-chassis rifle built? This very cool video from Masterpiece Arms answers that question. The nicely-edited video shows the creation of a Masterpiece Arms tactical rifle from start to finish. All aspects of the manufacturing process are illustrated: 3D CAD modeling, CNC milling of the chassis, barrel threading/contouring, chamber-reaming, barrel lapping, laser engraving, and stock coating. If you love to see machines at work, you will enjoy this video…
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Need a new barrel for your Rem-actioned hunting or tactical rifle? Here’s a great DIY option for riflemen. McRee’s Precision offers complete, no-gunsmithing re-barreling kits for Remington and Rem-clone actions. These feature a high-quality, pre-chambered “PRE-FIT” stainless barrel from Criterion, a Savage-style barrel nut, a recoil lug, and a special barrel-nut wrench. With this system you can easily re-barrel your favorite Remington rifle yourself in less than an hour. You don’t need to pay gunsmithing fees, or wait weeks (or months) for a busy smith to do the job. And the price is under $500.00. McRee’s Precision even offers a Half-MOA Accuracy Guarantee with its pre-fitted barrel kits. NOTE: Check MrReesPrecision.net on Thanksgiving for a Holiday Special Price (probably 10% Off).
McRee’s Precision Remington DIY Barrel Kit includes Criterion Pre-Fit Stainless Barrel, Barrel Nut, Recoil Lug, Thread Protector, and Barrel Nut Wrench: The stainless steel Barrel Nut is set up for 1 1/16 x 16 barrel threads, while the stainless steel recoil lug has a 1/8 inch removable locator pin and is set up for 1.0625 dia barrel threads.Barrel Kit Specifications.
McRee’s Precision sells Rem-action Pre-Fit barrel packages (complete with barrel nut, recoil lug, and wrench) starting at $499.52 (get a Holiday Discount on that price commencing 11/24/2016). Choose from five chamberings: .243 Win, 6.5 Creedmoor, .260 Rem, .308 Win, and .300 Win Mag. These Pre-Fit barrel kits are “100% complete and ready-to-install”. All you need to do is remove your current barrel, place the recoil lug, spin on the new tube, follow the instructions for setting head-space, then torque the barrel nut against the lug. NOTE: You may require a barrel vise and action wrench to remove the original barrel. Minor inletting changes may be needed forward of the action.
The folks at McRee’s Precision say their Pre-Fit system offers many advantages: “Remington Pre-Fitted Barrel Kits have become popular over the years. If Savage can do it, why not for our Remingtons? Our [Criterion-supplied] barrels are spec’d to the McRee standard of performance. There are several places to get the tools required to remove your factory barrel correctly. Once you have your barrel removed all you have to do is follow the normal Savage procedure to install your new barrel. We recommend that you contact your local gunsmith for the install. Feel free to call us with any questions.”
Product Tip from Ed LongRange. We welcome readers’ submissions.
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Kevin Muramatsu’s black rifle book, the Gun Digest Guide to Customizing Your AR-15, is a great resource for fans of AR-platform rifles. All the AR options you can imagine are covered: suppressors, premium barrels, adjustable stocks, free-float handguards, ergonomic grips, buffer systems, tactical lights and much more. Those planning an AR rifle build will find application-specific suggestions for 3-Gun, Service Rifle, High Power (Space Gun), Hunting, and Self-Defense use.
Firearms expert Muramatsu offers advice on choosing the right stock/barrel/optics configuration for your particular game. He also discusses the wide variety of options for slings, grips, magazines and other accessories. With over 520 photos, the book includes a large photo gallery of customized ARs, and includes bonus coverage of the FAL and other “tactical” firearms. The Gun Digest Guide to Customizing Your AR-15 is available from Amazon.com for $21.87, and a Kindle eBook version is offered for $14.99. The book is also sold by Barnes & Noble, and most other major booksellers.
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Next time you have a barrel fitted, consider having your gunsmith create a “stub gauge” from a left-over piece of barrel steel (ideally taken from your new barrel blank). The outside diameter isn’t important — the key thing is that the stub gauge is created with the same reamer used to chamber your current barrel, and the stub must have the same bore diameter, with the same land/groove configuration, as the barrel on your rifle. When properly made, a stub gauge gives you an accurate three-dimensional model of the upper section of your chamber and throat. This comes in handy when you need to bump your case shoulders. Just slide a fired case (with spent primer removed) in the stub gauge and measure from base of case to the end of the gauge. Then, after bumping, re-measure to confirm how much you’ve moved the shoulder.
In addition, the stub gauge lets you measure the original length to lands and freebore when your barrel was new. This gives you a baseline to accurately assess how far your throat erodes with use. Of course, as the throat wears, to get true length-to-lands dimension, you need take your measurement using your actual barrel. The barrel stub gauge helps you set the initial bullet seating depth. Seating depth is then adjusted accordingly, based on observed throat erosion, or your preferred seating depth.
Forum member RussT explains: “My gunsmith [makes a stub gauge] for me on every barrel now. I order a barrel an inch longer and that gives him enough material when he cuts off the end to give me a nice case gauge. Though I don’t have him cut that nice-looking window in the side (as shown in photos). That’s a neat option. You can tell how much throat erosion you are getting from when it was new as well. For measuring initial seating depths, this is the most useful item on my loading bench next to calipers. Everyone should have a case gauge made by their smith if you have a new barrel put on.”
Forum member Lawrence H. has stub gauges made with his chamber reamers for each new barrel He has his smith cut a port in the stub steel so Lawrence can actually see how the bullet engages the rifling in a newly-cut chamber. With this “view port”, one can also see how the case-neck fits in the chamber. Lawrence tells us: “My stub gauges are made from my barrels and cut with my chamber reamers. With them I can measure where my bullets are ‘touching the lands’ and shoulder bump dimensions. This is a very simple tool that provides accurate information.” The photos in this article show the stub gauges made for Lawrence by his gunsmith.
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Brownell’s has prepared a useful video showing how to remove light rust from a firearm. This shows how to use soft cloths, polishes, and 0000 steel wool to eliminate light surface rust. CAUTION — if you have a very high gloss blued finish, ANY abrasive and even the finest grade of oiled steel wool can scratch or alter the finish. With something like a $1200.00 “Royal Blue” Colt Python, it may be better to tolerate a few small pits than to work it over with steel wool.
Watch Brownell’s Video on Rust Removal
Brownell’s technician, Steve Ostrem, notes that many things can promote rust — some you might not expect. In addition to moisture in the air, rust can be caused by the salts and oils from your hands, sweat, blood, or even insect repellent. Ostrem also observes that temperature changes can produce condensation which may lead to rust inside the gun that you don’t even notice: “In the real world we know that if you take the gun outside, sooner or later, it’s going to rust. When you come inside, wipe the gun down the first opportunity you get. If you bring a cold gun into a warm, humid house, you’re going to have an instant coating of moisture… make sure you get the gun dried off and you’ll avoid a lot of problems.”
We’ve conducted a comprehensive test of corrosion-fighters. Among the best products to prevent rust are Boeshield T-9, Corrosion-X, and Eezox. Break-Free also works well, but it leaves a somewhat greasy residue, and it did not perform as well during long-term salt exposure as did the other three products.
For long-term storage, nothing beats a coating of Cosmoline, Rig or similar grease. This provides a barrier layer that blocks the oxidation process, which is how rust forms. These greases performed extremely well in a comparison test of Rust Preventative Products performed by Brownell’s. CLICK HERE for Comparison Test.
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Jewell triggers are still the most-used triggers on competition benchrest and F-Class rifles and they are also popular for hunting, varmint, and tactical rifles (with or without safeties). While a Jewell trigger can work for years with minimal maintenance, if the trigger becomes gunked up, it may be necessary to disassemble the trigger for a thorough cleaning. Our friends Ed and Steve, aka the 6.5 Guys, have produced a helpful video that shows how to disassemble and then reassemble a Jewell trigger.
Why You May Need to Disassemble Your Jewell Trigger — the 6.5 Guys
Jewell triggers are a popular choice in the sport of long range precision shooting, and like everything else require regular cleaning and maintenance. In most cases they can be cleaned with charcoal lighter fluid or dropped into an ultrasonic cleaner. Should the situation require, they can be completely disassembled according to the Jewell Trigger Manual.
We ran into a situation where we had to dissemble a trigger due to the entrapment of some sticky dirt that couldn’t be removed with an ultrasonic cleaner. Our first step was to find some step-by-step instructions but we couldn’t find anything.
Recognizing that other shooters might be in the same situation we produced a step-by-step guide and video, published in full on 65Guys.com. These instructions will work with a left- or right-handed trigger. In our case we worked with a left-handed BR model trigger with safety and bolt release.
Step-by-Step Instructions are provided on 65Guys.com website. We recommend you read all the instructions carefully before you even think about disassembling your trigger. This video explains the process so you can get a sense of what is involved.
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Forum member Mike T. (aka “Watercam”), has cleverly adapted a tubegun cheek piece to conventional fiberglass and wood stocks. The cheek piece hardware comes from Competition Machine and is the same as used on Gary Eliseo’s tubegun stocks. Here is Watercam’s Project Report:
Installing Tubegun Cheek Piece on Conventional Gun Stock
All of my match rifles are equipped with thumb-wheel adjustable cheek pieces for the best of reasons — adjustments can be made while in position, on target. I’ve learned that variations in position, terrain, and vertical angle all demand adjustability to achieve optimal cheek weld.
I wanted a cheek piece for my hunting and tactical type stocks that gave the same adjustability without having to cut a chunk off of my butt stocks. It needed to be affordable and easy to install. I also wanted a unit that would not push my head laterally away from the centerline of the scope or iron sights. Turns out I already had what I needed on my Gary Eliseo B-1 tubegun. I ran the idea past Gary, who said: “If you’ll be the guinea pig I’ll send the hardware”.
Using Gary’s hardware, I mounted Eliseo alloy thumb-wheel adjustable cheek pieces on a Bell & Carlson Medalist hunting stock and a Boyd’s laminate tactical stock. Read Forum Discussion.
Building Version One on Bell & Calson Stock
I had a Bell & Carlson Medalist stock for a Mauser 98 chambered in 9.3×62. This test rifle was enough of a thumper to reveal if the metal cheek piece could handle strong recoil.
I started by drilling three 1/2″ holes into the top of the comb to match the two pillars and one threaded shaft on the cheek piece. I used aluminum tubing to make guides for each and epoxied them in place. Inletting the oval hole for the thumb wheel was reasonably straight forward and the fiber reinforced foam in the buttstock offered enough support. A large flat washer epoxied underneath where the thumbwheel lay gave a smooth bearing surface. Total adjustment (with 2.25″ pillars and shafts) is just about an inch. I chose to trim the bottom of the skirt of Gary’s cheek plate so as to allow better position behind the scope for me and allow maximum adjustment even with the cheek piece of the stock. Set screws could be used instead of the thumb-wheel or in conjunction with it. In the end it was exactly what I envisioned and works great! The only thing left to do is paint the metal to match the stock.
Version Two — Installed on Boyds Laminated Tactical Stock
Watercam’s second metal cheek piece installation was on a laminated tactical stock. This Boyds stock did have a movable comb, but the original adjustable cheek section was too awkward to adjust from position. So I adapted the Eliseo cheek piece to to the Boyds stock, as you can see:
Cheek piece installation for both stocks was straight-forward, and the new cheek pieces work every bit as well the systems on my match rifles. Aluminum tubes epoxied in place guide the rods and threaded shank. A matching-diameter flat washer epoxied under the wheel provides smooth bearing surface. The glass-filled filler of the butt stock is plenty strong enough to support the unit. A set screw and knob can be added to lock in changes if so desired.
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Muzzle brakes are controversial. Some people swear by them, while others swear at them. Still, there’s no question that a good brake can reduce felt recoil up to 45%. And likewise, the best brakes, when installed properly, seem to have no negative effect on accuracy.
Roy Bertalotto has done considerable experimentation with muzzle brakes, testing dozens of brake designs on his own rifles over the past few years. Roy’s article, Adventures with Muzzle Brakes, discusses various aspects of muzzle brake design and performance. Roy doesn’t claim that his testing is definitive, but his article is definitely worth a read. Here are some of Roy’s interesting findings:
Exit Hole Diameter
“Best accuracy and effectiveness of the brake was obtained with a hole .020″ over bullet diameter. If the exit hole is too small, such as +.005″ over bullet diameter, accuracy suffers. If the depth of the exit hole is too shallow, the metal around the hole will erode very quickly.”
“The most effective braking was with a brake 1″ in diameter with a 3/4″ exit hole on each side, just in front of the muzzle. The bullet passes through a cone of 35 degrees before it exits the brake. (Like the tank example), Incredible reduction of recoil. But loud and ugly. Very easy to make since you don’t need a spin fixture or a dividing head.”
Bottom Gas Venting Helps Accuracy
“In my tests, not having holes all around the brake effects accuracy a bit. I believe it does something to the bullet by the air pushed ahead of the bullet creating unequal turbulence in the bullet path. I’ve tried a few brakes where I drilled only holes on the top, test fired, and then completed holes on the bottom and in every case, accuracy improved.” Below are spiral-ported brakes crafted by Clay Spencer.
Brakes Work Best with High-Pressure Cartridges
“The higher the pressure of the particular round, the more effective the brake. I have over 20 rifles with brakes. The 220 Swift is the king of reduction. Followed very closely by the 25-06, 6mm Remington, any Weatherby small bore. With a proper brake and a hot handload under a 40 gr bullet, the Swift will move 1/2″ to the rear and 0 muzzle rise! Big boomers with low pressure like 45-70s and shot guns benefit the least.” [Editor’s Note: Roy is judging effectiveness by the percentage of recoil reduction rather than absolute levels of recoil. Obviously if you start with a heavier-recoiling round, the absolute amount of recoil energy reduction is greater. Roy is really talking about efficiency–brakes are most efficient when used with high-pressure cartridges.]
Installation is Key to Accuracy
Roy’s findings are fascinating and suggest that further study of muzzle brakes is warranted. But we can all agree that precision installation of the brake is essential for accuracy. A poorly-installed, mis-aligned brake will degrade accuracy, that is well-known.
Harrell’s Precision has made thousands of muzzle brakes, in many styles and port arrangements. The Harrell brothers offer some good advice for gunsmiths installing brakes: “Muzzle brakes aren’t magic, they reduce recoil by redirecting exiting gas. What’s important is that they are straight and the threads are perpendicular with the base. The only way to get the base and threads perpendicular is to thread, not tap, them on a lathe.”
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The NRA’s American Rifleman showcased an interesting project this week — an upgraded Ruger American Rifle Predator in 6.5 Creedmoor. The video below shows how a laminated wood stock from Boyd’s Gunstocks was adapted for the Ruger. A Boyds Prairie Hunter model in gray laminate was selected. This was custom-bedded to the Ruger’s action using Brownell’s Acraglas.
All Ruger American Rifle models employ dual aluminum V-Blocks to support the action. These fit slots in the underside of the action. Boyds makes its own version of these V-Blocks which were installed in the Boyds stock to secure the action.
Project leader Joe Kurtenbach says the size, shape, and geometry of the Boyds V-Blocks is very accurate, so they fit the Ruger action well. To further support the action, Acraglas bedding compound was applied to the inside of the stock, after release compound was applied to the barreled action. With this DIY bedding job, the Boyds laminated stock is definitely an improvement over this original “Tupperware” factory stock.
DIY Bargain Hunter Upgrade
American Rifleman states: “The Ruger American has some great features—hammer-forged barrel, reliable action, crisp trigger — but many would not consider the molded, polymer stock to be among them. Luckily, there are aftermarket options to enhance the rifle’s utility and aesthetics. A durable, attractive stock from Boyds Gunstocks and some DIY action bedding, using Brownells Acraglas, is the next step in the precision-driven hunting rifle build.”
Choice of Gun and 6.5 Creedmoor Chambering
For this project, American Rifleman’s Joe Kurtenbach selected one of his favorite cartridges, the 6.5 Creedmoor. Introduced in 2007 by Hornady, the accurate, flat-shooting 6.5 Creedmoor has proven very popular with both hunters and tactical/PRS shooters. The Ruger American Rifle Predator was chosen for its affordable price, reliable action, and Ruger Marksman adjustable trigger.
In this video, Kurtenback explains how and why the 6.5 Creedmoor chambering and Ruger American Rifle were chosen for the Precision Hunter rifle build project.
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Readers 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.
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.
What is “Overbore”? That’s a question rifle shooters can debate to no end. This article from our archives proposes one way to identify “overbore cartridges”. We think the approach outlined here is quite useful, but we know that there are other ways to define cartridges with “overbore” properties. Whenever we run this article, it stimulates a healthy debate among our readers — and that is probably a good thing.
Forum Member John L. has been intrigued by the question of “overbore” cartridges. People generally agree that overbore designs can be “barrel burners”, but is there a way to predict barrel life based on how radically a case is “overbore”? John notes that there is no generally accepted definition of “overbore”. Based on analyses of a wide variety of cartridges, John hoped to create a comparative index to determine whether a cartridge is more or less “overbore”. This, in turn, might help us predict barrel life and maybe even predict the cartridge’s accuracy potential.
John tells us: “I have read countless discussions about overbore cartridges for years. There seemed to be some widely accepted, general rules of thumb as to what makes a case ‘overbore’. In the simplest terms, a very big case pushing a relatively small diameter bullet is acknowledged as the classic overbore design. But it’s not just large powder capacity that creates an overbore situation — it is the relationship between powder capacity and barrel bore diameter. Looking at those two factors, we can express the ‘Overbore Index’ as a mathematical formula — the case capacity in grains of water divided by the area (in square inches) of the bore cross-section. This gives us an Index which lets us compare various cartridge designs.”
OVERBORE INDEX Chart
So what do these numbers mean? John says: “My own conclusion from much reading and analysis is that cartridges with case volume to bore area ratio less than 900 are most likely easy on barrels and those greater than 1000 are hard on barrels.” John acknowledges, however, that these numbers are just for comparison purposes. One can’t simply use the Index number, by itself, to predict barrel life. For example, one cannot conclude that a 600 Index number cartridge will necessarily give twice the barrel life of a 1200 Index cartridge. However, John says, a lower index number “seems to be a good predictor of barrel life”.
John’s system, while not perfect, does give us a benchmark to compare various cartridge designs. If, for example, you’re trying to decide between a 6.5-284 and a 260 Remington, it makes sense to compare the “Overbore Index” number for both cartridges. Then, of course, you have to consider other factors such as powder type, pressure, velocity, bullet weight, and barrel hardness.
Overbore Cases and Accuracy
Barrel life may not be the only thing predicted by the ratio of powder capacity to bore cross-section area. John thinks that if we look at our most accurate cartridges, such as the 6 PPC, and 30 BR, there’s some indication that lower Index numbers are associated with greater inherent accuracy. This is only a theory. John notes: “While I do not have the facilities to validate the hypothesis that the case capacity to bore area ratio is a good predictor of accuracy — along with other well-known factors — it seems to be one important factor.”
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Planning to put together an AR-platform rifle? Or are you looking to upgrade your AR with a new barrel, stock, or trigger group? Then you should check out the AR-15 Rifle Build DVD from our friends at UltimateReloader.com. This DVD covers all the details of a custom build, using high-resolution video sequences, and helpful supporting graphics.
In this DVD, Gavin Gear guides you through the entire process including selecting components, acquiring and using the necessary tools, assembly steps and details for each component, and even mounting a scope. Building an AR-15 can be overwhelming, but with the right guidance and help it’s not difficult and is a lot of fun. With this DVD you’ll be able to build your AR-15 with confidence.
Right now, as a New Year’s promotion, the AR-15 Build DVD is on sale for just $9.90 (plus $3.80 shipping/handling). This DVD can pay for itself many times over by showing you how to do your own gunsmithing (and get quality AR components at attractive prices).
Upper: Barrel / Gas Block / Gas Tube
Upper: Handguard Installation:
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Here are some of the fine rifles Mike Bryant has smithed. You’ll find dozens more on BryantCustom.com.
Texas-based gunsmith Mike Bryant has decided to start taking work again. It seems that retired life was just a bit too sedate for Mike. This is great news for fans of precision rifles. Mike is an superb smith who has produced many match-winning competition rigs along with fine hunting and varmint rifles.
The services Mike can provide are listed on his “re-activated” website at BryantCustom.com. Mike will still continue to specialize in Rem Action-based and Custom Action-based rifles with customer-supplied parts. He explains his decision to return to the business he does so well: “Retirement was short with what the economy has done in the oil and gas business. I am back at least part time. I am Looking forward to serving my customer’s needs as I have done in the past.”
Welcome back Mike — we wish you success in your “return to the fold”. As before Mike will offer complete custom rifles as well as a full range of gunsmithing services including chambering, barrel-fitting, stocking, and action truing.
Here’s a bit of Britain in blue — a 270-7mm WSM F-Classer belonging to Elwood in the UK.
One of the most popular items in our Shooters’ Forum is the ongoing “Pride and Joy” thread. Since 2009, Forum members have posted photos and descriptions of their most prized rifles. Here are some of the most recent “Pride and Joy” rifles showcased in our Forum. Do you have a gun you’d like to see featured there? Just Register for the Forum and you can add your gun to the list.
1. Dasher LowBoy. CigarCop just completed a lovely 6mm Dasher in a yellow/gray laminated PR&T LowBoy stock. CigarCop did the stock inletting and finish work himself. Very nice work indeed.
2. Varmint Special. Here’s a handsome varminter with a beautifully-figured walnut stock. This is one of three rifles Forum Member Dan Hall posted this month.
3. 6mm Trifecta. DixiePPC served up not one but THREE pretty rifles, all with pearlescent paint jobs. Details of the three rigs are provided below. Click the image to see a full-screen version.
Top: 6 PPC for 10.5-lb NBRSA LV Class, 1:14″, .262″-necked SS Hart Barrel chambered and fitted by Doug Pascal, Pearl Black Kelbly Stock, RB/RP Blueprint & Trued 40X Short Action (Glued) with a Doug Pascal Bolt Release. This gun is a 1994 build by Doug Pascal of Craftsmith.
Middle: 6 PPC 13.5lb NBRSA HV Class, 1:14″, .262″-necked SS straight-countour Hart Barrel, Pearl White Kelbly Stock/Aluminum Butt Plate, RB/RP Stolle Panda Action (Glued). Kelbly Double Screw Rings. 1994 Vintage Leupold/Premier BR 36X. This gun is a 1992-vintage Kelbly build for NBRSA Unlimited Class.
Bottom: 6mmBR 17-lb IBS Light Gun Class, 28″, 1:8″, .268″-necked SS Bartlein 5R Barrel tipped with a SS Harrell Spiral Muzzle Brake, Pearl Rust Orange 90s-vintage Lee Six Stock with home made Aluminum Butt Plate, RB/RP Blueprinted and Trued 1995-Vintage 700 Short Action.
4. Simple Elegance. This is Chopper Duke’s handsome 6mm PPC. It features a Remington action in a classic older-style benchrest stock. We like the flawless pale-green finish. Subtle but nice.
5. (Nearly) Identical Duo. Here are a matching pair of customs from Forum member NHM16. He tells us: “I sold my two Savages I was using for F-Open, and had these two built in their place. One reason I upgraded was so I could have two (nearly) identical rifles. The nice thing about these rifles is that most everything interchanges, including the barrels.”
Here Are Specs for Both Guns:
— Panda F-Class action (LRBP, no ejector, 20 MOA dovetail scope base, one action is polished, the other unpolished so I could easily tell them apart).
— PR&T LowBoy stocks with adjustable buttplates, with vents on the side and the bottom.
— Both have Bartlein 32″ 7mm, 1:8″-twist, 5R barrels, chambered in 7mm Walker (basically a .284 Shehane with the addition of a 40 degree shoulder).
— Rifles were built by Richard King (“Kings X” in Forum) in Arlington, Texas, though I did the clear coating myself.
6. First Custom. Here is Forum member Barrys’s very first custom rifle, and it’s a nice one. It features a BAT Machine VR action, Krieger #17 heavy varmint contour, chambered for the 6mmBR Norma with 0.272″ neck. The stock is a Shehane Varmint Tracker with a Walnut-color laminated Obeche stock. On top is a Sightron SIII 8-32x56mm scope in BAT Machine rings.
7. Basic Black. David P. offered this F-TR rig: “A buddy of mine just finished up new rifle for NRA F-TR competition. This rifle is built on a Kelbly action, chambered in .308 Win with a custom, tight-neck match chamber. It’s sitting in a PR&T stock, with a Broughton 32″, 1:11″-twist 5C barrel. The rifle was chambered and built by Brian at Plainfield Precision in Shelby, NC.
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As a visual treat for our Daily Bulletin readers, we went back to our Gun of the Week archives to showcase a very special rifle. This humdinger could be the prettiest prone rifle we’ve ever seen. Commissioned for Forum member Corbin S., this is one handsome rifle, built with all-premium components and a stunning Curly Maple thumbhole stock with adjustable cheekpiece. The rifle is chambered in .243 Winchester. It features a custom stainless RBRP action Nesika R action, with keycuts in the bottom instead of recoil lug. A Grünig & Elmiger trigger has been specially modified (milled and pinned) to work with the Nesika action. The barrel is a 30″ Broughton 5R Palma-contour tube, and there is another 30″ Broughton 6BR barrel that Corbin uses at shorter ranges. The trigger guard, fore-arm rail, cheek adjuster, and 4-way adjustable butt assembly are all custom metal, designed by Dan Gleason. The stock is cut from exhibition-grade fiddleback maple (from Cecil Fredi Gunstocks in Las Vegas) with a Gaboon Ebony tip wood and butt-plate spacer.
Very Accurate with Fast-Flyin’ Berger 105s
Corbin tells us the gun will put five shots into the size of a quarter at 300 yards “when he does his part.” Corbin shoots pointed Berger 105gr VLDs and 45.5 grains of H4831SC. That load runs 3180 fps. He can push it faster, but “that’s where the node was and where it shoots best”, according to Corbin.
Forum member Jim Hardy has seen (and shot against) this beautiful rifle. He reports:
“A casual observer might think that the trigger guard, cheek plate and butt plate hardware are Anschutz — as the stock takes on the Anschutz prone pattern. However, this is ALL custom metal. The G&E trigger breaks like a glass rod and will makes my BR triggers feel inferior at best. I had the pleasure of holding, shouldering, and lusting over this gun at Camp Perry last year, and it is even more impressive in person. The killer is that there is yet ANOTHER one in a beautiful, dark figured walnut owned by Corbin’s shooting partner. BTW, both guns will hammer at 1000 yards prone.”
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Our friend Erik Cortina told us that Jim Borden of Borden Accuracy has developed a new “wide-body” action, the Borden BRMXD. Erik is building a rifle around this action to shoot at the 2016 Berger SW Nationals. The new BRMXD is Borden’s first venture into action bodies larger than 1.350″ in diameter. The round BRMXD action measures a stout 1.470″ in diameter and comes standard with bottom recoil lug. If the customer prefers, Border can deliver the action with a conventional recoil lug on the front. We like the looks of Borden’s new BRMXD, and we bet this new stainless action will be a smooth runner.
Borden BRM-XD Action Specifications:
• Action: BRM-XD
• Length: 8-1/8″
• Outside Diameter: 1.470″
• Port Length: Single Port: 2.750″
— Dual Port w/ Mini Port for BR / PPC: 2.750″ Loading & 1.8″ Eject Port
— Dual Port w/ x47 Family Port: 2.750″ Loading & 1.9″ Eject Port
— Dual Port w/ .284 Family Port: 2.750″ Loading & 2.4″ Eject Port
• Weight: 42.6 oz for Single Port
• Price: $1325.00 with bottom lug for a single port – $1400.00 for a dual port + shipping
• Price: $1250.00 for no lug (Glue-In Only)
Borden Accuracy will also offer a 0.215″ spacer for shooters who wish to use their current PANDA barrels with a new BRMXD action. This hardened steel spacer will cost $50.00 (introductory price).
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Here are the main tools you’ll need to assemble an AR-platform rifle
Planning to put together an AR-platform rifle? Or are you looking to upgrade your AR with a new barrel, stock, or trigger group? Then you should check out the AR-15 Rifle Build DVD from our friends at UltimateReloader.com. This DVD covers all the details of a custom build, using high-resolution video sequences, and helpful supporting graphics.
In this DVD, Gavin Gear guides you through the entire process including selecting components, acquiring and using the necessary tools, assembly steps and details for each component, and even mounting a scope. Building an AR-15 can be overwhelming, but with the right guidance and help it’s not difficult and can be very rewarding. With this DVD you’ll be able to build your AR-15 with confidence.
Upper: Barrel / Gas Block / Gas Tube
Upper: Handguard Installation
UltimateReloader.com’s AR-15 Build DVD is available just $9.90 (plus $3.80 shipping/handling). This DVD can pay for itself many times over by showing you how to do your own gunsmithing (and get quality AR components at attractive prices).
See Parts Installed in See-Through AR-15 Lower
This isn’t part of UltimateReloader.com DVD, but this YouTube video shows how to install the AR trigger group and other parts in an AR-15 lower. A transparent, see-through Tennessee Arms Company lower receiver was chosen to make it easier to see how the parts are installed.
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A while back, Roy Bertalotto acquired a budget-priced Kimber 82G rimfire target rifle from the CMP. The Kimber comes with an oiled-wood stock that works fine for three-position training, but Roy wanted to shoot the gun for the bench. The original Kimber stock, with its narrow, radiused forearm, was not ideal for this purpose. Roy wanted a wide, flat fore-end, which is much more stable in the bags. Rather that spend hundreds on a new benchrest stock, Roy modified his Kimber’s original stock by slicing a section off the bottom of the stock and then replacing this with a 3/4″ X 2 3/4″ X 15″ piece of walnut.
WATCH Project Stages in Slide-Show Below:
Roy explains: “The modification I did on my Kimber 82G stock was done using a milling machine, hand planes, files, die grinder and sand paper. It can also be done with simple hand tools — it will just take longer. The first step is removing the wood on the bottom of the fore-end. This was accomplished in the milling machine. A scrap piece of 2X8 was mounted to the milling machine’s table and the surface milled to be perfectly flat. The Kimber stock was screwed to this 2X8 with two large screws and the bottom of the stock was milled flat. Once this was done, a piece of 3/4″ X 2 3/4″ X 15″ walnut was glued using West System epoxy to the cut out area. I use West System epoxy in boat building, but any good wood glue will work.”
After gluing the new bottom piece in place, Roy milled the sides to provide side flats with a radius to transition from the wider lower section to the narrower upper part of the fore-end. As a added enhancement, Roy contoured the rear of the fore-end to blend with the rear of the stock, adding what he calls “1965 Ford Mustang side scoops”. Roy then used a Die Grinder with a 1.5″ sanding wheel to modify the wrist area to provide more thumb relief.
Following the cutting, milling, gluing, and shaping, Roy sanded with 150 grit and 300 grit sandpaper before applying multiple coats of Tung Oil. Once the main stock was completed, Roy completed the project by crafting an extended buttplate from a couple pieces of 1/8″ aluminum and two 1.5″ aluminum tubes, “all polished to a slightly less than mirror finish”. NOTE: This metal buttplate assembly was made from scratch (other than the pad). This is not an aftermarket extension kit.
Overall the gun turned out very nicely. Log on to Roy’s RVB Precision webpage to learn more about this Kimber stock modification project, and view more photos of the building process.
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