For the very first day of 2023 we present a precision rifle built with a relatively new cartridge — the 6GT. Developed by George Gardner of G.A. Precision and Tom Jacobs of Vapor Trail Bullets, the 6GT was designed to have the efficiency of a 6mm Dasher without the need for case forming. It was also designed with a longer case body so it feeds better from magazines. Even with the added capacity, the 6GT is still very efficient, and can achieve good velocities with less powder than a 6mm Creedmoor.
Today’s Sunday Gunday feature rifle was smithed and tested by Gavin Gear of UltimateReloader.com. Gavin did all the gunsmithing — chambering the barrel, fitting the muzzle brake, and even laser engraving the barrel. In building this 6GT rifle, Gavin used top-tier components: BAT TR action, Krieger 28″ 1:7.5″-twist 4-groove 6mm barrel, TriggerTech Diamond Rem 700-compatible trigger, and Area 419 Hellfire Muzzle Brake. The barreled action was then fitted in a handsome and rugged MDT ACC Chassis. On top is a Zero Tech 4.5-27×50mm FFP Trace Advanced scope in 30mm Hawkins Precision high rings.
We recommend you watch the video above — it covers the rifle build, load development, and then features some remarkable shooting sequences across snowy hills in the Pacific Northwest. Gavin’s team actually used a drone to capture overhead footage of the location.
After developing a promising load with Berger 109gr LRHT bullets, Varget powder, and Alpha brass, Gavin literally headed for the hills to test his new rifle at longer ranges, shooting from bipod. His load had shot well under half-MOA at 100 yards in testing so he was hoping he could hit multiple steel targets positioned at 340 yards, 760 yards, and 1000 yards. Indeed he did, proving the rifle’s great accuracy and Gavin’s fine trigger-pulling skills. You can see the hits at these time points in the above video:
340 Yards — 18:15 time | 760 Yards — 19:00 time | 1000 Yards — 19:54 Time
Gavin’s 6GT Hit Highlights on Steel out to 1000 Yards
Building Gavin’s 6GT Precision Rifle
Gavin Gear did all the gunsmithing on this project, using his own Precision Matthews TL-1660 lathe for the chambering with an Alpha carbide 6GT reamer. The barrel work took about four hours total. Shown below is the reamer cutting the chamber, which was finished with a 0.170″ freebore and 0.270″ neck diameter. For other brands of brass you might want the chamber to have a larger 0.272″ neck diameter.
Chambering the Krieger barrel with Alpha carbide 6GT reamer, 0.170” freebore, .270″ neck diameter.
This project when smoothly, with Gavin able to install the barreled action in the MDT Chassis and fit the buttstock in an hour or so. So total build time was about five hours. One nice “finishing touch” on the project was laser engraving the 28″ Krieger barrel — a process you can see in the video below.
Laser engraving of Krieger 28″ barrel.
About the 6GT — Sort of a 6 Dasher on Steroids
6GT Cartridge Design Features
The 6GT was designed to have an optimal length and capacity for mag-fed PRS/NRL tactical rifles. The 6GT is longer than a 6mmBR and 6 Dasher, but shorter than a 6mm Creedmoor and 6.5×47 Lapua. That gives the 6GT ample case body length to feed reliably from a magazine, while the case capacity is sufficient to run popular powders at reasonable pressures. It has a 35-degree shoulder angle.
On paper the 6GT seemed like the perfect cartridge for PRS- and NRL-style centerfire competition. It has the low recoil of a 6 Dasher, with good feeding and mag compatibility. With the 6GT, a competitor can push 6mm 105gr bullets at 3000+ FPS or run heavier bullets at ~2950 FPS. With this 28″ Krieger barrel, Gavin actually achieved 3004 FPS running 109gr Bergers.
Gavin started with quality Alpha Munitions brass. The cases were then annealed with an AMP Annealer and trimmed to length with a Henderson powered trimmer (see video below). After sizing with a Forster Co-Ax press, Federal SR Primers were seated using a Primal Rights competition seater. Next the powder was measured with an A&D FX120i force restoration scale. Finally, the Berger 109gr LR Hybrid Target bullets were seated with a Forster Micrometer die, again using the smooth Forster Co-Ax press.
Initial Load Testing with Berger and Hornady Projectiles
Before it got cold and snowy, Gavin did load development, shooting from a bench with a Sinclair front rest. The Krieger cut-rifled barrel was accurate right from the start and Hodgdon Varget powder proved to be a very good choice for the 6GT.
Gavin’s 6GT boasts a MDT ACC short action chassis with SRS-X Elite buttstock, vertical grip, and MDT CKYE-POD Bipod.
Gavin did initial load testing with both Hornady 110gr A-Tip Match and Berger 109gr Long Range Hybrid Target bullets. The Berger 109gr LRHT bullets were the most promising. A variety of charge weights were tested, with Gavin settling on 34.6 grains of Varget. This delivered fine accuracy with a 3004 FPS muzzle velocity. Group size measurements with this load are shown in the chart. At 100 yards, four three-shot groups averaged 0.361 MOA, and the rifle produced a nice 0.387 MOA (0.405″) five-shot group.
———————————————— Winter Wonderland for Shooters ———————————————–
Coming Soon — Ultimate Reloader Rifles Business
Gavin Gear is in the process of opening his own gunsmithing business. He will be offering a variety of custom-built rifles for multiple disciplines — hunting, PRS/NRL, ELR, and other competitive disciplines. Gavin explains: “Ultimate Reloader is gearing up to do custom rifle work for the general public starting (hopefully) in Spring 2022. We will most likely start with complete custom rifle builds using parts from our inventory. We will focus on high-end, bolt-action rifle builds and gunsmithing, primarily Remington 700 and clones. We will entertain limited gunsmithing work outside of complete builds (i.e. chambering, muzzle threading).
As we release this story, the East Coast has just entered a new year 2023. Perhaps you’ve been eagerly awaiting for the big event, getting champagne (and sparklers) to celebrate the New Year. 2023 will hopefully be a much better year than 2022, a tough year with inflation, the border crisis, War in Ukraine, and shocking incompetence in Washington. To mark the dawning of 2023, with hope for a much better year, we expect many folks will open a bottle of champagne. You could pop the cork the traditional way, or read on and learn how to release the celebratory champagne with a rifle shot, as demonstrated by the talented Kirsten Joy Weiss.
Recently at Thorton Winery in Temecula, California, a champagne vintner, we were shown the best way to open a champagne bottle. We were told you should hold the bottle nose up at an angle then rotate the BOTTLE slowly while holding the cork. That works great… but it’s not as stunning as the way sharpshooter Kirsten Joy Weiss opens a bottle of bubbly.
A former competitive smallbore rifle shooter, ace trigger-puller Kirsten Joy Weiss tried a special New Year’s trick shot a few seasons back. In keeping with the festive New Year’s spirit, Kirsten attempted to shoot the cork off a champagne bottle. After a few unsuccessful tries, she managed to hit the cork with at least two shots. But alas the cork did not fly. She actually hit the cork, but it did not release. That was surprising…
Undaunted, Kirsten changed her strategy, aiming for the neck of the bottle. This duplicates the process of “sabering” a champagne bottle — a method of liberating the bubbly by slashing off the end of the neck with a blade. Aiming for the neck of the bottle, Kirsten successfully blew off the top of the bottle. (Apparently, when “sabering” it is actually the pressure within the champagne bottle which does most of the work).
UltimateReloader.com offers some of the most thorough firearms and reloading tool tests on the internet. And UltimateReloader’s YouTube Channel has hundreds of great videos that showcase reloading tools, accurate firearms, precision optics, gunsmithing methods, and top-tier reloading components. For today’s Saturday at the Movies feature, we showcase six great videos recently created by Gavin Gear and his UltimateReloader team. These videos highlight a superb Long-Range Target Camera, the remarkable AMP Press, the new Hornady PRC cartridges, and other interesting topics. On this final day of 2022, enjoy our Saturday Video Showcase.
With the high price of centerfire powders, bullets, and brass, everyone should have an accurate .22 LR rimfire rifle for marksmanship training and competition at 25 to 200 yards. In this video, Ultimate Reloader’s Gavin Gear tests the impressive Anschutz 54.18 BR50-U7 match rifle using a quality Sinclair Int’l front rest. Anschutz offers several versions of the 54.18 and BR-50. There are two barreled actions available: 20″ threaded and 25.9″ non-threaded. Gavin tested the 20″ threaded model with the U7 stock. In this video, Gavin tested the trigger with a sophisticated TriggerScan TS-11. The trigger was superbly repeatable at a measured 3.8 ounces. Gavin also did a bore examination. He then tested the Anschutz with a variety of premium ammo. In this rifle, Lapua Midas+ producing the smallest groups. FULL STORY HERE.
This video features the impressive, high-tech AMP Bullet Seating Press. The AMP Press combines a motor driven ram, a distance sensor, and a load cell to deliver extremely accurate and precise force/distance bullet seating measurements. The AMP Press offers unrivaled consistency in the bullet seating process. And as the AMP Press is linked to a computer, seating data can be stored and you can chart variations in seating resistance. A wealth of precise data is collected during the bullet seating process. This helps you optimize your brass prep and annealing for the best, most consistent results. FULL STORY HERE.
Past 400 yards or so, it can be difficult to see bullet holes on paper, even with spotting scopes. That’s why we recommend a high-quality wireless target camera. The best long-range target cameras on the market are produced by Longshot Camera Systems. The Longshot Target Cam provides a live WiFi camera feed. This comes back to your shooting station and you can view the image with a laptop or mobile device. You don’t need internet coverage and no separate tall antennas are required. Simply place the camera unit next to your target and the receiver unit close to your rifle or bench. The Longshot system is completely self-contained. Longshot produces a variety of cameras starting at $449.00 for the LongShot Marksman. We recommend the $899.00 LR-3 unit which works out to two miles! In this video Gavin Gear of UltimateReloader tests the LR-3 at long range. PRODUCT INFO HERE.
This video examines how muzzle brakes reduce recoil. Just how important is bore clearance for a muzzle brake? Should you have an exit diameter that’s just slightly larger than bullet diameter, or will a larger diameter work well also? Along with no brake at all (bare muzzle), Ultimate Reloader tested multiple different brake bore clearances on a 6.5 Creedmoor rifle: 0.010″ over bullet diameter, 0.020″, 0.030″, 0.050″, 0.100″, and 0.200″. The testers expected to get the best recoil reduction with the tightest fit. Surprisingly, this wasn’t quite the case.
Using all brake configurations (all bore clearances) Ultimate Reloader saw a significant reduction in recoil, almost half, as compared to a bare muzzle: “What we didn’t expect was how close together the rest of the clearances would cluster. All of the clearances that we tested had good recoil reduction.” FULL STORY HERE.
Dillon Precision continues to be the leader among progressive press makers. Dillon offers the largest variety of progressives, the most accessories, and legendary customer service. In this video, Gavin Gear of Ultimate Reloader looks at a variety of Dillon machines to help buyers decide which progressive best suits their needs. Featured Dillon progressives include: Square Deal B, Xl750, and RL1100. Along with basic press feature, Gavin shows the operation of Dillon’s automated bullet feeder and case feeder accessories. The video also provides pricing summaries with various configurations. FULL STORY HERE.
Hornady’s PRC (Precision Rifle Cartridge) family of cartridges are becoming quite popular. The 6.5 PRC fits in a short action, while the 7mm PRC and 300 PRC both require a long action. The 7mm PRC is a long-action centerfire hunting cartridge designed to shoot 180gr bullets at 2950+ FPS. The 6.5 PRC is a good hunting cartridge that can fit a standard-length action. And, a number of top F-Open shooters are necking up the 6.5 PRC for 7mm bullets. This 7-6.5 PRC wildcat has shown excellent F-Class accuracy with a higher velocity node than the .284 Winchester. Along with these two cartridges, Hornady has a 300 PRC that can shoot the big .308-caliber bullets. In this video, Ultimate Reloader analyzes and compares each of the three PRC cartridge types. FULL STORY HERE.
With major forest fires this past year in Western states, many have wondered about hazards faced by gun owners in fire zones. This important video shows what really happens when loaded ammunition burns. You will probably be surprised. Contrary to Hollywood notions, the ammo doesn’t ignite in a massive explosion. Far from it… basically the rounds “cook off” one by one, and the bullets release at relatively low velocity. We’ve featured this SAAMI research project before, but it is worth reprising for those who have not yet seen the burn tests.
A few years back, SAAMI released an important video concerning ammo and fire. With professional fire-fighters standing by, over 400,000 rounds of ammo were incinerated in a series of eye-opening tests. If you haven’t had the chance to view this video yet, you should take the time to watch it now
The Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) has produced an amazing 25-minute video that shows what actually happens to sporting ammunition involved in a fire. This video shows the results of serious tests conducted with the assistance of professional fire crews. We strongly recommend you watch this video, all the way through. It dispels many myths, while demonstrating what really happens when ammunition is burned, dropped, or crushed.
Watch SAAMI Ammunition Testing Video
Video Timeline
2:10 Impact Test (ignited outside firearm)
3:40 65-foot Drop Test
5:08 Bullet Impact (.308 Win firing)
7:55 Blasting Cap Attacks
9:55 Bulldozer and Forklift Tests
12:20 Boxed Ammo Bonfire
15:37 Bonfire without Packaging
17:21 Retail Store Simulation Burn
20:55 Truck Trailer Burn
Over 400,000 rounds of ammunition were used in the tests. Some of the footage is quite remarkable. Testers built a bonfire with 28,000 rounds of boxed ammo soaked in diesel fuel. Then the testers loaded five pallets of ammo (250,000 rounds) in the back of a semi-truck, and torched it all using wood and paper fire-starting materials doused with diesel fuel.
The video shows that, when ammo boxes are set on fire, and ammunition does discharge, the bullet normally exits at low speed and low pressure. SAAMI states: “Smokeless powders must be confined to propel a projectile at high velocity. When not in a firearm, projectile velocities are extremely low.” At distances of 10 meters, bullets launched from “cooked-off” ammo would not penetrate the normal “turn-out gear” worn by fire-fighters.
We are not suggesting you disregard the risks of ammo “cooking off” in a fire, but you will learn the realities of the situation by watching the video. There are some amazing demonstrations — including a simulated retail store fire with 115,000 rounds of ammo in boxes. As cartridges cook off, it sounds like a battery of machine-guns, but projectiles did not penetrate the “store” walls, or even two layers of sheet-rock. The fire crew puts out the “store fire” easily in under 20 seconds, just using water.
Additional Testing: Drop Test, Projectile Test, Crush Test, Blasting Cap Test
Drop Test
The video also offers interesting ammo-handling tests. Boxes of ammo were dropped from a height of 65 feet. Only a tiny fraction of the cartridges discharged, and there was no chain-fire. SAAMI concludes: “When dropped from extreme heights (65 feet), sporting ammunition is unlikely to ignite. If a cartridge ignites, it does not propagate.”
Rifle Fire Test
SAAMI’s testers even tried to blow up boxes of ammunition with rifle fire. Boxes of loaded ammo were shot with .308 Win rounds from 65 yards. The video includes fascinating slow-motion footage showing rounds penetrating boxes of rifle cartridges, pistol ammo, and shotgun shells. Individual cartridges that were penetrated were destroyed, but adjacent cartridges suffered little damage, other than some powder leakage. SAAMI observed: “Most of the ammunition did not ignite. When a cartridge did ignite, there was no chain reaction.”
Bulldozer Crush Test
The test team also did an amazing “crush-test” using a Bulldozer. First boxes of loaded ammo, then loose piles of ammo, were crushed under the treads of a Bulldozer. A handful of rounds fired off, but again there was no chain-fire, and no large explosion. SAAMI observed: “Even in the most extreme conditions of compression and friction, sporting ammunition is unlikely to ignite. [If it does ignite when crushed] it does not propagate.”
Blasting Cap Test
Perhaps most amazingly, the testers were not able to get ammunition to chain-fire (detonate all at once), even when using blasting caps affixed directly to live primers. In the SAAMI test, a blasting cap was placed on the primer of a round housed in a large box of ammo. One cartridge ignited but the rest of the boxed ammo was relatively undamaged and there was no propagation.
The paper targets you use can make a big difference during load development and training — helping you align your crosshairs, estimate group size visually, and also record load data/gun type. Here’s a collection of FREE printable precision and training targets. This selection includes popular load development targets AccurateShooter created as well as other useful grid targets. You can download ALL these targets as PDF files and then print them out on 8.5×11″ heavy paper.
AccurateShooter.com offers an online archive with over 50 FREE downloadable targets. You’ll find all types of FREE targets — sight-in targets, varmint targets, rimfire targets, bullseye targets, tactical targets, load development targets and more. CLICK HERE for all our free targets, including our LOAD DEV target.
Since we created this target a decade ago, it has proven very popular as a load development target, since all your load data fits neatly in the boxes under each target. In fact this target is used by both rifle-makers and barrel-makers (including Criterion) to test their products. The diamonds have 1/2″ sides and you can align your cross-hairs on the horizontal and vertical lines. It is a clean design that is easy to see even at 200 yards. When we test, we usually crank in a little elevation, setting the point-of-impact higher. That way our shots land in the gray circles, leaving the red squares intact for precise aiming.
This is a nicely-designed six-bull grid target. Use this for load development or accuracy testing. Set your scope so you can aim at the orange diamonds while your shots impact in the box above. This target has a visible background grid so it is easy to estimate your group size. You’ll find other load development targets in this Shooters’ Forum Thread.
Five Diamond Grid Targets
Here’s a popular grid target with multiple red diamond aiming points. The background includes a grid pattern with 1″ squares — that helps to quickly estimate group size through your scope. We recommend using a color printer for this target so the diamonds and grid lines are bright red.
We use the two targets below for load development and precision practice. For the left target, use the corners of the diamonds to align your cross-hairs precisely. The circle dot target (on the right) can also be used for informal rimfire competition at 50 yards. Right-Click Each Target to Download Printable PDFs.
Know-Your-Limits Target for Rimfire Training & Fun Matches
Here’s a rimfire training target with “big to small” target circles. Start with the largest circles, then move to the smaller ones in sequence. This systematic drill provides increasing challenge shot-by-shot. Novices often are quite surprised to see their accuracy improve as they move from bigger to smaller aiming points. That provides positive feedback — always a good thing.
This target was created using Open Office (Draw) by Forum member TwoBoxer for 100-yard load development and practice. He tells us: “The color, size of the center dot, crosshair lines, etc. were varied to work with my scope and magnification at 100 yards. I expect the group POI to move as elements of the load are varied. So concern about obliterating the aim point is minimal, and needs to be controlled by how you zero the rifle in any case.”
RED Center Pistol Target
Here’s a NRA-type target for pistol shooting. The bright red center helps when shooting indoors because well-placed bullet holes are much more visible. This target includes data entry boxes to record gun type, score, and load data. This is one of many good free targets available at Targets4free.com.
The Pew Pew Tactical website has interesting article on rifle and pistol cartridges and bullet types. This contains a large selection of interesting photographs and illustrations. If you load and/or shoot for a wide variety of cartridge types, you’ll find that article well worth reading. It has nearly 50 photographs and more than a dozen short videos. READ FULL Article.
The article shows all types of pistol bullets, along with a variety of rifle projectiles. It even illustrates multiple types of shotshell cartridges.
The article also explains the basic components of modern cartridges –bullet, case, powder, and primer:
Photo courtesy Ammunitiontogo.com which sells ammo from many leading brands.
Popular Cartridge Types Profiled
The article provides quick summaries of popular ammunition types including 9mm Luger (9x19mm), .357 Magnum, .40 SW, .45 ACP, .223 Rem, and .308 Winchester. The author’s favorite pistol round is the 9mm Luger: “9mm is my personal favorite and if there was a “Goldilocks” round, this would be it. The very first gun I bought was a 9mm. They’re fun at the range. They’re good for defense. It is the standard round for NATO countries and the majority of police forces around the world. It is mild shooting, can vary in weight from 115 to 147 grains, and has varying stopping power based on the type of bullet.”
This Pew-Pew Tactical guide to cartridge types also provides a quick explanation of cartridge ignition — both centerfire and rimfire: “The rimfire’s primer is built into the rim while the centerfire cartridge has the primer in the center. Pro tip — if you can see a circle in the middle…it’s a centerfire cartridge.”
There are two common types of centerfire primers — Boxer and Berdan. This helpful Wikipedia illustration shows how Boxer, Berdan, and rimfire primers ignite the powder in the cartridge:
This centerfire and rimfire ignition animation is by BBODO – Own work, CC BY-SA 3.0 licensed under the Creative Commons Attribution-Share Alike 3.0 license.
Many shooters these days clean their cartridge brass ultrasonically, or wet-tumble their cases with stainless media (above). Both methods get brass clean and shiny, inside and out. However, when those wet-cleaning processes are completed, you’re left with a pile of soaking wet brass. How do you dry your brass quickly and efficiently, without unsightly water spots? Read on for some great answers…
In our Shooters’ Forum, Member Terry asked: “How do you dry your brass after Ultrasonic cleaning?” In a Reloading Forum Thread, many smart suggestions were posted. A dozen fellow members outlined a variety of effective case-drying procedures, which work equally well for both wet-tumbled brass and ultrasonically-cleaned cases. Here are the Top 10 brass-drying suggestions from our Forum members.
TOP TEN Ways to Dry Cartridge Brass After Wet Cleaning
1. Food Dehydrator — Shake the brass in towel to get the bulk of water off. Next leave in the food dehydrator for 45 minutes or until there are no signs of moisture inside the cases. — Lawrence97
2. Lyman 5-Level Case Dryer — Rinse off cleaning solution(s), then load brass by type into racks in Lyman Cyclone Case Dryer. This is easier to load/unload than food dehydrators and holds more cases.
3. Hot Water + Compressed Air — Rinse all your cases as a batch using scalding hot water from the kitchen sink. Hot water evaporates off of brass very very quickly. Then hit them with compressed air. Takes 10 minutes. Simple. — SG4247
4. Oven Dry in Pre-Heated Oven — After pre-heating to 200° or so, turn off oven and put brass inside on a tray. Most important! Tell your wife what you are doing so she doesn’t crank it up to 425 to heat pizza! — MClark
NOTE: Many other members suggested oven drying at 150-200°. We recommend turning OFF the oven so you don’t cook your brass if you forget to remove the cases.
5. Towel Dry then Warm with Heat Gun — Roll brass in a towel until no more water shakes out. Lay out on cardboard box top and blow off with Harbor Freight heat gun. $9.99 on coupon. Two minutes of heated air and about half hour of wait and they are good to go. This is with primers removed. — Shaggy357
6. Compressed Air, then Sun Dry Outside – I rinse the brass, then blow them out with compressed air. Then, dependent on the time of year, lay them on a towel in the sun. — HogPatrol
7. Dishwasher on Dry Cycle – In the winter, I drop my wet brass cases neck-down on the rack pegs in the dishwasher, then turn on the dry cycle. In the summer…well, I’m in Texas. They go to the porch for a bit. — Toolbreaker
8. Alcohol Rinse then Air or Oven Dry — Rinse in 90% Isopropyl alcohol and either let air dry or stick in 175° oven for half an hour. Alternatively, use a dehydrator. — Zipollini
9. Slow Air-Dry in Loading Blocks — I have a reloading block with holes drilled in it. I simply load the block up and let it air-dry in the cupboard for a couple of days. — JCS
10. Wipe with Towel Then Anneal Normally — This thread is stirring my OCD side. Seems complicated for just drying — my brass dries just fine when I anneal it. This entire process can’t take an hour per batch. When finished, the brass is cleaned, annealed, and ready to size. — CHLuke
Deprime, then tumble brass with stainless media, water, Lemishine, and dish detergent.
Shake them easily in a strainer to knock out most media then grab 4-5 pieces, shake them over the bucket for the last of the media then inside a towel.
Finally blow out the primer pockets and wipe with a towel, load in the Annealeez.
Matchlocks, Wheellocks, Flintlocks, Breechloaders, Lever Actions — All these historically significant firearms designs (and more) are featured in a fascinating series of videos produced by Ruger.
Sturm, Ruger & Co. has created a series of 11 short videos that trace the history of firearms, from matchlocks to modern semi-autos. Ruger’s “History of the Gun” video series provides a fascinating look at firearms technology throughout the years. The host is Garry James, Senior Editor of Guns & Ammo magazine. Featured here is Segment 7 on Rifling. Other installments in the series are linked below. If you are interested in the history of gun design and manufacturing, this series is definitely worth watching.
One Shooters’ Forum member asked: “What makes an AR accurate? What parts on an AR can really affect accuracy — such as free-floating handguards, barrels, bolts, bolt carriers?” He wanted an honest, well-informed answer, not just sales pitches. Robert Whitley posted a very detailed answer to this question, based on his experience building/testing scores of AR-platform rifles. Robert runs AR-X Enterprises, which produces match-grade uppers for High Power competitors, tactical shooters, and varminters.
Building an Accurate AR — What is Most Important
by Robert Whitley
There are a lot of things that can be done to an AR to enhance consistent accuracy, and I use the words “consistent accuracy” because consistency is a part of it (i.e. plenty of guns will give a couple great 5-shot groups, but won’t do a very good 10- or 20-shot groups, and some guns will shoot great one day and not so good on others).
Here are 14 key things we think are important to accuracy.
1. Great Barrel: You’ll want a premium match-grade barrel, well-machined with a good crown and a match-type chambering, true to the bore and well cut. The extension threads must also be cut true to the bore, with everything true and in proper alignment.
2. Rigid Upper: A rigid, heavy-walled upper receiver aids accuracy. The typical AR upper receiver was made for a lightweight carry rifle and they stripped all the metal they could off it to make it light to carry (which is advantageous for the military). The net result are upper receivers that are so thin you can flex them with your bare hands. These flexible uppers are “strong enough” for general use, but they are not ideal for accuracy. Accuracy improves with a more rigid upper receiver.
3. True Receiver Face: We’ve found that truing the receiver face is valuable. Some may argue this point but it is always best to keep everything related to the barrel and the bore in complete alignment with the bore (i.e. barrel extension, bolt, upper receiver, carrier, etc.).
4. Barrel Extension: You should Loctite or glue the barrel extension into the upper receiver. This holds it in place all the way front to back in the upper receiver. Otherwise if there is any play (and there typically is) it just hangs on the face of the upper receiver completely dependent on the face of the upper receiver as the sole source of support for the barrel as opposed to being made more an integral part of the upper receiver by being glued-in.
5. Gas Block: You want a gas block that does not impose pointed stress on the barrel. Clamp-on types that grab all the way around the barrel are excellent. The blocks that are pinned on with tapered pins that wedge against the barrel or the slip on type of block with set screws that push up from underneath (or directly on the barrel) can deform the bore inside of the barrel and can wreck the accuracy of an otherwise great barrel.
6. Free-Float Handguard: A rigid, free-float handguard (and I emphasize the word rigid) really makes a difference. There are many types of free-float handguards and a free-float handguard is, in and of itself, a huge improvement over a non-free-float set up, but best is a rigid set-up. Some of the ones on the market are small diameter, thin and/or flexible and if you are shooting off any type of rest, bipod, front bag, etc., a rigid fore-end is best since ARs want to jump, bounce and twist when you let a shot go, as the carrier starts to begin its cycle before the bullet exits the bore.
7. Barrel Contour: You want some meat on the barrel. Between the upper receiver and the gas block don’t go real thin with a barrel (we like 1″ diameter if it’s workable weight-wise). When you touch off a round and the bullet passes the gas port, the gas system immediately starts pressuring up with a gas impulse that provides vibrations and stress on the barrel, especially between the gas block back to the receiver. A heavier barrel here dampens that. Staying a little heavier with barrel contour through the gas block area and out to the muzzle is good for the same reasons. ARs have a lot going on when you touch off a round and the gas system pressures up and the carrier starts moving (all before the bullet exits the bore) so the more things are made heavier and rigid to counteract that the better — within reason (I’m not advocating a 12-lb barrel).
8. Gas Tube Routing Clearance: You want a gas tube that runs freely through the barrel nut, through the front of the upper receiver, and through the gas key in the carrier. Ensure the gas tube is not impinged by any of them, so that it does not load the carrier in a stressed orientation. You don’t want the gas tube bound up so that when the gas tube pressures up it immediately wants to transmit more force and impulse to the barrel than would normally occur. We sometimes spend a lot of time moving the gas block with gas tube on and off new build uppers and tweaking gas tubes to get proper clearance and alignment. Most gas tubes do need a little “tweaking” to get them right — factory tubes may work OK but they typically do not function optimally without hand-fitting.
9. Gas Port Tuning: You want to avoid over-porting the gas port. Being over-gassed makes the gas system pressure up earlier and more aggressively. This causes more impulse, and increases forces and vibration affecting the top end and the barrel. Tune the gas port to give the amount of pressure needed to function properly and adequately but no more.
10. Front/Back Bolt Play: If accuracy is the game, don’t leave a lot of front/back bolt play (keep it .003″ but no more than .005″). We’ve seen factory rifles run .012″ to .015″ play, which is OK if you need to leave room for dirt and grime in a military application. However, that amount of play is not ideal for a high-accuracy AR build. A lot of front/back bolt play allows rounds to be hammered into the chamber and actually re-formed in a non-consistent way, as they are loaded into the chamber.
11. Component Quality: Use good parts from a reputable source and be wary of “gun show specials”. All parts are NOT the same. Some are good, some are not so good, and some aftermarket parts are simply bad. Don’t be afraid to use mil-spec-type carriers; by and large they are excellent for an accuracy build. Also, remember that just because a carrier says “National Match” or something else on it does not necessarily mean it’s any better. Be wary of chrome-plated parts as the chrome plating can change the parts dimensionally and can also make it hard to do hand-fitting for fit and function.
12. Upper to Lower Fit: A good upper/lower fit is helpful. For quick and dirty fit enhancement, an Accu-Wedge in the rear helps a lot. The ultimate solution is to bed the upper to a specific lower so that the upper and lower, when together, are more like one integral unit. For the upper receivers we produce, we try to get the specs as close as we can, but still fit the various lowers in the market place.
13. Muzzle Attachments: Don’t screw up the muzzle (literally). Leave as much metal on the barrel at the muzzle as you can. People like to thread the muzzle for a flash hider, suppressor, muzzle brake, or some other attachment, but if you really want accuracy, leave as much metal as you can there. And, if you have something that screws on, set it up so that it can be put on and have it stay there without putting a lot of torque and stress on it right where the bullet exits the bore. If you are going to thread the end of the barrel, make it concentric with the bore and make sure what you screw on there is as well. For all muzzle attachments, also ensure that the holes through which the bullet passes through are dead true to the bore. Many aftermarket screw-on things are not so good that way. Anything that vents gas should vent symmetrically (i.e. if it vents left, it should vent equally right, and likewise, if it vents up, it should vent down equally). Uneven venting of gas can wreck accuracy.
14. Quality Ammunition: Ammo is a whole story by itself, but loads that are too hot typically shoot poorly in an AR-15. If you want accuracy out of an AR-15, avoid overly hot loads. Shown below are test groups shot with four (4) different uppers, all with moderate loads. These four uppers all pretty much had the same features and things done to them as explained in this article, and they all shot great.
Here’s a “must-read” article for .22 LR rimfire shooters. The October 2018 issue of Shooting Sports USA (SSUSA) includes a great article with data on thirty-one (31) different types of popular .22 LR rimfire ammunition. The line-up includes low-speed, standard, and Hi-Velocity types, plus choices for plinking, varminting, and target applications. Brands tested include: Aguila, American Eagle, CCI, Federal, Fiocchi, Lapua, Remington, and Winchester. The slowest ammo, CCI Quiet-22 Lead RN, clocked 727 FPS. The fastest ammo, CCI Short-Range Green Lead-Free HP, ran 1735 FPS, 2.4 times the speed of the Quiet-22.
For each ammo type, SSUSA lists the bullet weight, velocity (FPS), and average of two, 5-shot groups at fifty yards. The most accurate ammo was Lapua Center-X LRN, with a 0.37″ average 50-yard group size. Second best was Lapua X-ACT LRN at 0.42″. Ammo was tested from a bench with a Cooper Model 57-M rifle fitted with 3-9x33mm Leupold VX-2 scope. The ammo offerings were grouped into three categories: (1) Varmints/Small Game; (2) Target; and (3) Plinking. (See ammo tables below.)
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Different types of .22 LR (Long Rifle) rimfire ammo have different applications. Subsonic ammo, typically, is best for 25m to 50m target work with precision rimfire rigs. Hi-Velocity .22 LR ammo provides a flatter trajectory for longer ranges. SSUSA explains: “The array of .22 LR loads… turns a person’s head every which way. Subsonic target loads are the key to decisive accuracy on targets, while hyper-velocity cartridges provide striking bullet expansion on small varmints. In between, standard and high-velocity .22 LRs are loaded with a variety of bullet weights and styles for everything from small-game hunting to plinking[.]” READ Full SSUSA .22 LR Rimfire Ammo Story.
A former competitive smallbore rifle shooter, ace trigger-puller Kirsten Joy Weiss tried a special New Year’s trick shot a few seasons back. In keeping with the festive New Year’s spirit, Kirsten attempted to shoot the cork off a champagne bottle. After a few unsuccessful tries, she managed to hit the cork with at least two shots. But alas the cork did not fly. She actually hit the cork, but it did not release. That was surprising…
The Sporting Arms and Ammunition Manufacturers’ Institute (
We are not suggesting you disregard the risks of ammo “cooking off” in a fire, but you will learn the realities of the situation by watching the video. There are some amazing demonstrations — including a simulated retail store fire with 115,000 rounds of ammo in boxes. As cartridges cook off, it sounds like a battery of machine-guns, but projectiles did not penetrate the “store” walls, or even two layers of sheet-rock. The fire crew puts out the “store fire” easily in under 20 seconds, just using water.
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Popular Cartridge Types Profiled
5. Towel Dry then Warm with Heat Gun — Roll brass in a towel until no more water shakes out. Lay out on cardboard box top and blow off with Harbor Freight heat gun. $9.99 on coupon. Two minutes of heated air and about half hour of wait and they are good to go. This is with primers removed. — Shaggy357
5. Gas Block: You want a gas block that does not impose pointed stress on the barrel. Clamp-on types that grab all the way around the barrel are excellent. The blocks that are pinned on with tapered pins that wedge against the barrel or the slip on type of block with set screws that push up from underneath (or directly on the barrel) can deform the bore inside of the barrel and can wreck the accuracy of an otherwise great barrel.
