Larry Vickers is a respected firearms trainer who has served with the U.S. Special Operations Forces (SOF). In the course of teaching classes he’s learned that many gun owners waste money on impractical gun accessories. In a well-reasoned Ammoland.com article, “Don’t Be a Tacti-Cool Fool”, Vickers examines today’s trend of over-accessorizing firearms, particularly AR-platform rifles. Vickers doesn’t mince words… he states that too many people are spending too much money on poorly-designed hardware that may be “useless” at best.
Equipment Selection Advice from Larry Vickers
Every class I teach I see and hear students talking about the realization that some things about their gear and shooting in general just doesn’t add up on the range. Everything looks good in a Brownells Catalog but a significant amount of the parts and accessories offered on the market today are: a) useless; b) poorly designed; c) of questionable value; or d) downright dangerous.
No one is better at taking fully-functional, factory-made firearms and turning them into junk than a certain segment of the American gun-buying public.
Some people really don’t apply the common sense approach of not messing with what is potentially a life-saving tool. Sadly some of those same people will get on the Internet and talk bad about how the firearm they modified no longer functions and therefore is junk. Or they will recommend to fellow shooters the same parts and modifications they have used to turn their gun into, at best, a range toy.
Some of this shows up in my classes and usually by lunch on the first day the obvious flaws of the equipment at hand become apparent for everyone in the class, most of all to the owner of said equipment. It may have cost the shooter some money but in turn he learned a serious life lesson –be careful what you read on the Internet about firearms modifications and there is no substitute for shaking out your equipment at the range in a structured class.
I’ve said it before and I’ll say it again: you’ll learn more about guns and shooting in one class than you could in a month on the Internet.
READ about guns, gear, and shooting on the Internet. LEARN about guns, gear, and shooting on the range during well-thought-out and useful training. This approach is proven and consistently produces results and shooter confidence.
Larry Vickers is a retired U.S. Army Special Operations Forces veteran with 20+ years of service. Vickers served in Panama, the Middle East (Desert Storm), Somalia, Bosnia, and other locations. During his time with Delta Force, Vickers worked on weapons R&D, and served as a combat marksmanship instructor training new operational members of Delta.
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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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For affordable, low-recoil shooting fun it’s hard to beat a semi-auto .22 LR. While Ruger’s 10/22 is the most popular semi-auto .22 LR rifle, manufacturers are now offering AR-style self-loading rimfire rifles. We like AR-style .22LR rigs for Rimfire Tactical Matches and 3-Gun cross-training. With an AR-style rimfire rifle you can train with low-cost ammunition while enjoying the same ergonomics, controls, and sighting systems found on your centerfire ARs.
Smith & Wesson has upgraded its M&P 15-22, a fun rifle that we’ve praised in the past. The new M&P 15-22 Sport MOE SL model (Magpul Original Equipment Slim Line) features a more comfortable handguard, an improved grip, and an adjustable Magpul buttstock. The dedicated .22 LR M&P rifle retains the look and features of the company’s popular M&P rifle line, with the enhanced ergonomics of Magpul furniture. It’s offered with Flat Dark Earth (tan) furniture or dressed in matte black.
These rimfire versions of the AR-15 are excellent training tools for 3-Gun and service rifle shooters. You can practice with less expensive rimfire ammo, and save wear and tear on your centerfire ARs. Rimfire AR clones also work great for Rimfire Tactical Matches.
Field Testing the Smith & Wesson M&P 15-22
Smith & Wesson’s 15-22 is a nice little rifle. The M&P 15-22 is designed and built as a true .22 LR semi-auto from the ground up, with ergonomics (and most controls) identical to a centerfire M&P 15 rifle. NRA reviewer Colon Noir tested the M&P 15-22 and was impressed: “This gun is unbelievably fun to shoot. There is virtually no recoil. The non-existent recoil makes shooting fast a breeze. Yeah, the magazine is a little quirky… but in the grand scheme of things, this gun feels like a full-out AR-15. The M&P 15-22 makes for a great training companion. I would place this gun in the ‘Fun Box’ — it’s reliable enough that you can have a fun time shooting. I’m picking one up, because it’s guns like these that make you truly realize how fun shooting is.”
Here’s a Video Review of the M&P 15-22 by the NRA’s Colin Noir
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Let’s face it, AR-platform rifles run dirty, at least compared to typical bolt-action rifles. The AR15 works by piping gas from the barrel back into the bolt carrier, causing the bolt to unlock and the carrier to move the bolt backward. The “exhaust gas” from the barrel contains soot and carbon. The carbon will form hard deposits on the bolt. In addition, the carbon can combine with lube on the bolt carrier to make a nasty, paste-like sludge. This can be particularly problematic when the black paste pollutes the ejector and extractor recess.
This Editor has inspected dozens of ARs over the years. Other than mag-related malfunctions, the most common cause of AR cycling problems I found was oily gunk in the extractor and ejector areas. Many AR owners overlook these critical areas. Look at an AR that hasn’t been cleaned properly and you’ll probably find black gunk (and small brass shavings) in the ejector and extractor recesses.
If you want to keep your black rifle running smoothly and reliably, you must clean it regularly and follow the correct maintenance procedures. Here are three videos that explain how to properly disassemble and clean AR-platform rifles.
Take-Down and Full Cleaning of AR15 by Jerry Miculek
Here ace shooter Jerry Miculek takes down and cleans an AR-platform rifle belonging to his daughter Lena. This is a good video because Lena’s rifle was “run hard and packed up dirty” so you can see where carbon and grease build up. This 35-minute video is very thorough. Jerry is one of the nation’s top action carbine shooters, so listen carefully to his advice on cleaning and lubrication.
How to Clean Your AR-Platform Rifle
This is a good basic video that shows the take-down and cleaning procedure for a typical AR15. It uses some fast-motion sequences to speed up the story. Check out this video if you don’t have the time to sit through the Miculek video above.
Cleaning and Lubricating AR15 Bolt Carrier Group
This video offers very specific advice on the bolt carrier group, which receives the dirty gas directly from the barrel. Be sure to check the extractor and ejector recesses. That’s where old lube, brass shavings, and carbon accumulate. Follow the directions in this video for lubrication, and don’t over-lubricate the bolt carrier — that will only capture more carbon.
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At SHOT Show 2017, Nosler showcased a new .22-caliber cartridge designed for AR-platform rifles. Called the 22 Nosler, the new cartridge resembles a 6.8 SPC necked down to .22 caliber. Comparing Nosler’s ammo specs with Hodgdon load data, it looks like the 22 Nosler can deliver about 250-300 fps more velocity than the standard .223 Rem cartridge. That’s significant for varminters looking for higher performance from an AR15-type rifle. With a 55-grain bullet, highest possible velocity is 3500+ fps with a max load of Hodgdon CFE 223 powder, based on this Nosler Load Chart:
Nosler will produce 22 Nosler ammunition in various bullet weights, starting with 55 grain and 77 grain. To run the 22 Nosler, an AR owner will need a new upper and 6.8 SPC type magazines. This video explains how to convert your AR-platform rifle to run the 22 Nosler.
“Everything Old Is New Again…”
Examining the 22 Nosler cartridge, our friend Grant Ubl had a case of “deja vu”. He thinks the new 22 Nosler bears a striking resemblance to a wildcat from the 1960s: “The .22 Nosler looks like a throwback to the 1963-vintage .224 Winchester E5 experimental cartridge, right down to the rebated rim.” Here is an old Winchester print:
Another poster said this cartridge resembles the “.220 Thunderbolt” a wildcat devised by John Scandale in 2004. Posting on Facebook, Mr. Scandale said the designs were very similar. According to Keystone Accuracy, the .220 Thunderbolt’s “design origin came from the now largely popular 6mm Hagar in its infancy stage back in 2003.” While it looks very similar to a 6.8 SPC necked to .224, the .220 Thunderbolt is different because the 6mm Hagar brass is 0.100″ longer than 6.8 SPC. Read History of .220 Thunderbolt.
Neck-up the 22 Nosler to .25 Caliber?
Dan Z. has inspected in the 22 Nosler ammunition and he’d like to see a .25 Caliber version. On Facebook, Dan posted: “I got my hands on some of the ammo a couple weeks ago. It does look like a .223 that has its body diameter expanded to that of a 6.8. Consequently, it is longer than the 6.8 overall and in the body. I necked a piece of fired brass to 6.8 and it looked like it would provide some improvement in velocity. A more interesting idea might be to neck it to .25 as a .250 Savage performance clone in an AR-15 platform.”
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The NRA has released new, updated versions of Competition Rules, with changes that have been adopted for 2016. There are quite a few minor changes affecting rifle competitors in High Power, Service Rifle, Prone AR Platform Rifle, F-Class, and Smallbore Disciplines. There are also new rules for matches with Electronic Targets.
You can download the updated rules, discipline by discipline, on the NRA Rulebook Page: http://rulebooks.nra.org. Bound copies of NRA Rule Books may be ordered online from the NRA Store: http://materials.nrahq.org.
Getting started in the shooting sports can be intimidating, especially for women. Thankfully, there are many training resources available. NSSF has compiled a series of target shooting tips for women, by women. These tips, presented by instructors Deb Ferns, Kay Miculek, and Lena Miculek-Afentul, cover basic shooting methods and safety. Topics include pistol grip, stance, eye dominance, and ear protection. These tips can benefit any novice shooter, not just the ladies.
Rifle Stance and Hold (for Action Shooting)
Champion 3-Gun shooters Kay Miculek and Lena Miculek-Afentul demonstrate rifle stance basics and how to properly hold an AR-platform rifle for action shooting.
Grip and Stance for Pistol Shooting
Mother/daughter team Kay Miculek and Lena Miculek-Afentul demonstrate proper grip and stance for shooting semi-automatic pistols in action disciplines.
Eye Dominance (and Hand/Eye Cross-Dominance)
Learn how to identify your dominant eye. Kay Miculek, a cross-dominant shooter, explains how other cross-dominant individuals can maintain a proper sight picture.
Ear Protection — Double-Up for Safety
Babes with Bullets Director Deb Ferns says the most common complaint among new shooters is, “It’s too loud!” Deb recommends “doubling up” — wearing muffs OVER soft foam earplugs. That’s “sound advice” for any shooter.
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In her latest video, Kirsten Joy Weiss shows off the 300 AAC Blackout, a popular .30-caliber cartridge for AR-platform rifles. Kirsten explains the advantages for the 300 BLK for hunters as well as those using an AR for self-defense. The 300 BLK is popular with suppressor owners because it works well with heavy bullets launched at subsonic velocities.
Reasons to Shoot a 300 AAC Blackout:
— You can use your current AR Bolt, Bolt Carrier, Buffer, and Magazine. The only part you need to change is the barrel.
— 300 BLK conforms to state hunting regulations which may require a cartridge larger than .22 Caliber. The 300 BLK shoots .308 caliber bullets.
— Lapua now sells 300 AAC Blackout brass so no case-forming is required. Just load and shoot.
— You can shoot light bullets supersonic or heavier bullets subsonic. The subsonic capabilities of the 300 BLK make it ideal for use with a suppressed AR.
— With a .30-caliber bore and a modest powder charge, barrel life is outstanding with the 300 BLK.
— You can make 300 BLK cartridges from fired .223 Rem brass, which is plentiful and cheap.
— The .300 BLK performs well with some very accurate powders, such as Hodgdon H4198 and IMR 4227.
The 300 AAC Blackout was created by Advanced Armament Corp. and Remington primarily for the military as a way to shoot .30-caliber bullets from the M4/AR15 platform while using standard magazines. As explained by Robert Silvers, AAC’s R&D Director: “Now there is a way to shoot 30 caliber from your AR while still using normal magazines with full capacity. Even the bolt stays the same, and all that changes is the barrel.” For more information visit www.300aacblackout.com and download the 300 BLK Cartridge Information Guide (PDF).
SAAMI, the industry standards organization, adopted and standardized the AAC 300 Blackout in 2010. The SAAMI diagram for the 300 BLK is shown above. Lapua now makes 300 BLK cartridge brass.
300 BLK for 3-Gun Competition
The 300 AAC Blackout has been touted as an important new hunting round, but we see it more as a specialized “rule-beater” 30-cal option that lets 3-Gun competitors “make major” with a low-recoil cartridge that also offers long barrel life. For those who need to run a .30-caliber cartridge from a standard AR15 platform (as opposed to the AR10), the 300 AAC Blackout makes some sense. But for hunters using a bolt gun, there are any number of tried and true options, such as the 7.62×39, .30-30, and, of course, the .308 Winchester (7.62×51 NATO).
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Do you like black rifles? Do you suffer from an irrepressible desire to modify, tweak, and upgrade every little component on your ARs? Then check out “Everything AR” in the GUNS Magazine Combat Special Edition. From upgrades and accessories to brand reviews and insight into AR operating systems, the Fall/Winter 2014 GUNS Magazine Combat Special Edition is a cover-to-cover AR love-fest.
This 194-page Special Edition includes a helpful review of direct gas versus piston operating systems by Richard Mann. Another article by this same writer, “Pistol Caliber Carbine Perfection”, explores the evolution of pistol-caliber AR carbines, discussing pros and cons of several pistol calibers. Publisher/editor Roy Huntington contributes a story on Black Rain Ordnance, a company known for its high-quality AR-platform rifles, and lifetime warranty.
Want gadgets for your AR? In “Ten Got-To-Have Accessories For Your MSR,” contributing editor Dave Douglas spotlights some of the best bolt-ons for “Modern Sporting Rifles”, from sling mounts and LED lasers to sights and rubber grips.
The Fall/Winter 2014 issue of GUNS Combat includes the all-new 2015 Buyer’s Guide. This 128-page, comprehensive catalog features hundreds of products ranging from all types of handguns and long guns, to knives, lights and lasers
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Who is buying ARs and AKs, and in what quantities? Jim Curcuruto, NSSF’s Director of Industry Research, answers those questions in the May 2014 Issue of AR Guns & Hunting. In this interesting article about “Modern Sporting Rifles” (MSRs), Curcuruto provides answers to questions such as “How many Americans own an MSR?”, “Why are they being purchased?”, and “Who is buying them?”.
What the Heck is a ‘Modern Sporting Rifle’?
The term “Modern Sporting Rifles” is used to describe “AR- and AK-Platform rifles” — semi-automatic rifles with detachable box magazines. These are generally derivative of the original AR15/M16 or AK47 designs, although Modern Sporting Rifles may have different furniture, modular components, and scope rails in place of iron sights. Note: The “AR” in “AR-15″ rifle stands for ArmaLite rifle, after the company that developed it in the 1950s. “AR” does NOT stand for “assault rifle” or “automatic rifle.”
MSR Questions and Answers
Q: How may AR-type and AK-type rifles have been sold in recent years?
We don’t have an exact sales number. However, since 1990, over 8,200,000 MSRs have been “brought to market” in the USA. This is based on manufacturing stats, ATF sales records, as well as International Trade Commission (ITC) import numbers.
Q: How Many Americans Own MSRs?
A: 4.8 million American have an AR-type or AK-type rifle, according to a consumer survey and ATF and ITC statistics.
Q: What Kind of People Purchase MSRs?
A: MSRs are purchased by successful, educated people: “The average MSR owner is 35+ years old, married and has at least some college education. 54% of MSR owners have a household income of more than $75,000 and they are spending approximately $1,060 on each MSR[.]” Roughly one-third of MSR owners are active or former law enforcement or military personnel.
Q: Why Do People Purchase ARs and AKs?
A: The main reason Americans purchase MSRs is for “recreational target shooting”. The second most important reason is for home defense.
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Compared to bolt-action rifles, direct gas impingement AR-platform rifles tend to be filthy, maintenance-intensive beasts, requiring regular disassembly and cleaning of the innards. Op-rod style AR variants run cleaner and cooler, but they still require regular maintenance. Now there is a versatile, compact multi-tool that performs a variety of critical servicing/maintenance tasks for AR-platform rifles.
Weighing just 6 ounces, the new D-CAT from Space Age Weaponry fits in the storage compartment of a standard AR-15 fixed butt stock. Brownells says the D-CAT (“Deployable Compact Armorer’s Tool”) is the “only tool necessary to assemble the AR-15/M16 from component parts, or perform a complete disassembly”. The video below explains the feature and functions of the $149.99D-CAT.
The D-CAT is made from quality materials: 6061-T6 Aircraft Aluminum, 303 Stainless steel, and H13 Tool Steel. Bits, punches, and other small parts are located in the tool magazine, within the torque handle. Simply rotate the magazine gate to expose the individual compartments. Within the magazine you will find a 1/8″ punch, a flat blade driver, front sight adjustment tool, and a 3/16″ and 9/64″ hex driver. There is also a spare punch pocket and a Hammer/Trigger pin pocket. This is also the mode in which the D-CAT is used as a screwdriver. The driver makes use of a standard ¼” hex well so the tool can be augmented to serve as a general purpose driver for any bit you choose to carry.
Tool Tip from EdLongrange. We welcome reader submissions.
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In our Shooters’ Forum, one member posed the question: “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 comprehensive answer to this question, based on his experience building and testing dozens 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 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.
Do you like black rifles? Do you suffer from an irrepressible desire to modify, tweak, and upgrade every little component on your ARs? Then check out “Everything AR” in the 
Q: How Many Americans Own MSRs?
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.
