McKee: Expert Advice on Care and Feeding of Your AR-15, AR-10, M1, & M14

Fulton Armory Gas Guns Lineup

Over 25 years ago, Clint McKee started Fulton Armory to build fine M14 rifles, and the business has grown to include selling and servicing all of the U.S. standard-issue gas-operated rifles of the 20th Century: the M14 (M1A), M1 Garand, M1 Carbine, AR-15, and AR-10, as well as virtually everything needed to care for these legendary rifles Fulton Armory uses original USGI receivers in its M1 Garands, and because original USGI M14, AR-15, and AR-10 receivers have never been available to the U.S. commercial market, and due to scarcity of serviceable original USGI M1 carbines, Fulton Armory has faithfully recreated semi-automatic versions of these receivers that meet all USGI material, heat treat, and geometry specifications. Indeed, Fulton Armory is the only company in the world that manufactures receivers for the M14 (M1A), M1 Carbine, AR-15, and AR-10 type receivers.

Fulton Armory’s Clint McKee holds one of the company’s M14 Service Rifles
Fulton Armory’s Clint McKee holds one of the company’s M14 Service Rifles. Along with the FN-FAL and the AK-47, the M14 is considered to be one of the finest military rifles ever issued. Adopted in 1957, the M14 has been used in every US conflict since Vietnam and after over 50 years, still remains the most highly coveted US issue rifle in American inventory.

Also, McKee has collaborated with Dr. Walter Kuleck on detailed books about the country’s favorite battle rifles: The M14 Complete Assembly Guide, The M1 Garand Complete Assembly Guide, and The AR-15 Complete Assembly Guide, and others.

The Cheaper Than Dirt! Chronicle recently had a chance to pose a few questions to McKee about care and feeding of these wonderful rifles.

CTD: Many thousands of Cheaper Than Dirt! customers are newish AR-15 owners who are still feeling their way around the rifle. Where do they start if they want to learn the basics?

McKee: For care and feeding, The AR-15 Complete Owner’s Guide can help them through the basics—familiarization, history, maintenance, etc.—and, for complete assembly, disassembly, and parts replacement, The AR-15 Complete Assembly Guide shows step-by-step instructions, along with detailed photos of every aspect of their AR-15-type rifles. Together, they offer a lot of maintenance tips and tricks, complete assembly/disassembly, part replacement, safety checks, etc. that experienced AR-15 enthusiasts and armorers have discovered over the years. It will make you a more knowledgeable owner of the “Swiss Army Knife” of rifles and allow you to do almost anything an armorer could do should the need arise!

CTD: What’s the best $5 we can spend for our ARs?
McKee: A chamber brush. If you do nothing else to your rifle, you must keep the chamber clean. It’s a safety issue. When the chamber brush is easy to insert and remove, it’s worn out—you need a new one—an Accu-Wedge. Personally, I find a rattletrap rifle very annoying. The Accu-Wedge does not hurt accuracy, and it eliminates the rattletrap noise between the upper and lower receiver. In addition, it helps dampen and protect the impact on the pivot and takedown pins.

CTD: What’s better in an M1 Garand: .308 Win. or .30-06?
McKee: They are both wonderful cartridges. The .30-06, with its long tapered case, is easier to extract and adds about 100 feet-per-second to velocity. A definite advantage at 1000 yards. The .308, on the other hand, is generally more available and is nearly as powerful in a much more efficient package. Both function and perform superbly when properly barrelled in an M1 Garand.

Perhaps a better question is, What type of .30-06 or .308 cartridge is appropriate for the Garand?

Here are my recommendations:
The best choices for the M14 (M1A), AR-10, and the M1 Garand are bullets with full metal jackets or full metal jackets with polymer tips, e.g., Hornady A-Max and V-Max or Nosler Ballistic Tip, as well as the boat-tail hollowpoint bullets with an open but pointy tip, e.g., the 168-grain Sierra MatchKing. The point here is (pun intended) gas guns use the bullet tip to navigate the cartridge into the chamber.

CTD: Other cartridge advice?
McKee: Do not use lead-tipped bullets in gas guns. Lead tips can mushroom in magazines, and pieces of the lead tip can break off, get into the chamber and create a safety hazard.

Never exceed a bullet weight of 175 grains in gas guns. So, do not use 180s, 190s, and so on in these gas-operated rifles. Once a bullet’s weight exceeds 175 grains, slower-burning powders must be used to keep chamber pressures safe. There’s no problem for bolt guns—there’s no gas system—but for gas guns, the slower-burning powders greatly increase gas-port pressures, which can cause the rifle to literally beat itself to death.

Also, buy only first-quality ammunition in its original packaging. Packaging helps determine what the ammo has been exposed to and its condition, and, has lot numbers to identify the ammo if there’s a problem.

While we are on that subject, do not buy or use the .308 win/7.62×51 “cbc75” headstamped ammunition. It has blown up all kinds rifles coast-to-coast.

CTD: What about shooting at 800 or 1000 yards?
McKee: At 1000 yards, the M1 Garand using the .30-06 cartridge offers a real advantage. The .30-06 cartridge has the wonderful ability to offer a little bit more power at reduced chamber pressure levels. Though it seems odd that the .30-06 has less chamber pressure than the .308 and yet a bit more power, it’s nonetheless true. And, since it’s the original caliber, it works. The real difference is cost and availability of ammo. The .308 will be easier to find and less expensive. It’s really a personal choice. Either selection can be the right one.

And, for state-of-the-art long-range precision, there is nothing more accurate than our FAR.308 Titan, an AR-10 type rifle chambered in 6.5 Creedmoor—a remarkable cartridge. It’s supersonic beyond 1200 yards; has a very flat trajectory, and is intensely accurate. In the future, we will be offering this chambering in our M14s (M1As).

CTD: Here’s a question we get in customer service every day: “What’s the difference between 5.56mm and .223 Remington chambers in the AR-15 rifle?””
McKee: If we are talking about .223 Remington SAAMI-spec chambers in an AR-15, do not use such a chambering if you ever plan on shooting any military NATO 5.56 ammo, which happens to be the most common, least expensive, and most widely used AR-15 cartridge available in all the world. In other words, never buy a .223 SAAMI-spec chamber in a battle rifle, especially if the barrel and chamber are chromed, as you cannot fix it!. Here’s the problem. Many NATO cartridges have bullets that will become jammed into the rifling of a SAAMI chambering because the throat is too short. This is very dangerous for a number of reasons.

CTD: So a standard 5.56 chamber is a better choice?
McKee: Fulton Armory uses a hybrid 5.56 Match chambering in our AR-15 type rifles, uppers and barrels. That’s a slightly modified SAAMI chamber with a tad longer throat to accommodate NATO bullets. The Fulton Armory 5.56 Match chamber allows for the safe and reliable use of all SAAMI and NATO ammo, while offering the accuracy potential of the SAAMI chamberings with match commercial cartridges.

CTD: Why do you sell the Krieger AR barrels with a 1-in-7 twist and the other barrel with 1-in-8 twist instead of the 1-in-9 twist? Reports from the military say that the 1-in-7 twist burns out quicker.
McKee: We sell Krieger barrels for the AR-15 in 1-in-7.75 twist rates as well as our National Match barrel in 1-in-8. All things being equal, the faster the twist, the quicker it will wear out. But things are never equal.

The faster twists are used to stabilize heavier bullets, and since heavier bullets have slower velocities, it wears less—kind of a Catch-22. The rule of thumb is, for 55-grainers and less, 1-in-12 is ideal. For 55- to 69-grainers, use 1-in-9 twist. For 75- to 77-grain bullets, pick 1-in-7.7 or 1-in-8 twist. And for 80-grain bullets, use a 1-in-7 twist. The best general-purpose, all-round twist and longest-lasting picks would be our 1-in-8 twist and 1-in-9 twist chrome-lined barrels.

CTD: For rifle lubrication, when do you use oil, and when do you use grease?
McKee: Oil is bad for semi-automatics. The robust cycling of the action throws oil all over the place. Grease is better in almost every situation. To be more specific, we use Tetra Oil and Tetra Grease for lubrication in specific kinds of mechanisms.

CTD: Could you be more specific?
McKee: Tetra Oil, or any oil for that matter, should only be used as a primary lubricant in captivated assemblies that do not have robust movement. For example, crankcases in engines and motors are sealed, as oil is designed fly around inside it, and lubricate all the moving parts contained within it. Of course, if the crankcase were not sealed, the oil would go everywhere. The same thing applies to gas guns and recoil-operated firearms.

CTD: For small parts?
McKee: We use Tetra Oil on parts such as springs, detents, plungers, gears, screws, levers, slides and so on, but only when enclosed in a housing, or in applications where inertial energy will not bleed out its effectiveness. In addition, Tetra Oil is a fabulous protectant due to its hydrophobicity, impregnation of the treated metal and corrosion resistance. For areas not enclosed, use Tetra Grease instead. And put lots of grease on recoil springs.

CTD: Is Tetra Oil okay to use in barrels?
McKee: Tetra Oil is terrific for treating barrel bores. The active ingredient, PTFE, actually gets imbedded into the metal surface and makes cleaning a dream.

CTD: It seems that rifle makers charge more for a two-stage trigger. Is it worth the extra money?
McKee: Most civilian rifle triggers are single stage. When you place your finger on it and apply pressure, the trigger shouldn’t move at all, until it “breaks” and the gun fires. If the trigger does move before firing, it’s called creep. Creep is when you think you are trying to fire, but you just seem to keep pulling the trigger and it does not break cleanly. Creep is found in both single- and double-stage triggers. Take-up describes the smooth trigger movement found in the first stage of a two-stage trigger. The first stage takes up part of the total pull weight of a gas gun, which requires a far greater pull weight than bolt guns to be safe and legal for competition. It’s nice to split the pull weight between two stages, instead of one. You pull through the first stage, and when you get to the “stop,” you know any movement of the trigger will fire the rifle.

CTD: Why don’t you condone reloading for the US Gas Operated Service Rifles?
McKee: What firearms manufacturer recommends reloads, or warrants the product for such? In all the world? One might reasonably ask “Why?” Well, there’s all the obvious stuff. Then, there’s destruction, maiming and death. Most of you are vastly more educated than I am about reloading, and I apologize for my ignorance, and, for disappointing you with my very unpopular position. So, why in the world don’t I just get with it and give you a load of the month? Because, I do not want you to get hurt.

CTD: Hundreds of thousands of people reload in the U.S.
McKee: It’s 50,000 psi only a few inches from your face. A supplier I know well in the military rifle business lost his eye using reloads in his Ruger Mini-14. A man I know well, who has been building NM Service Rifles and Match rifles for 25 years, blew up a customer rifle while test firing. His reloads? Military match M16s reloads that disintegrated. I knew a good guy who was killed by a surplus rifle shooting reloads. And so it goes. This stuff only needs to happen once in your lifetime.

CTD: And for those who will reload anyway?
McKee: Keep the following in mind:

  • If you make a sizing mistake—overall cartridge length, case length or headspace of case—in a bolt gun, you can feel the problem. The bolt won’t close. Nobody gets hurt. In a gas gun, due to its substantial inertial energy, it will shove the proverbial 10 pounds of crap into a five-pound bag. I have seen an M14/M1A chamber six .308 Win. cartridges with its headspace dimensions as much as .008-inch oversized—and they fired. Then, when the seventh round chambered and fired, the rifle blew itself apart.
  • Many gas guns have free-floating firing pins, which actually dent the primer upon loading. Bolt guns do not do this. Try it at the range sometime. From a magazine, load one cartridge and then extract it without firing. Look closely at the primer and you’ll see a little dent in it. That’s why gas guns need hard mil-spec primers. Not just any primer will do. [For more on the topic of slamfires, click here.]
  • Gas guns are very hard on brass. During the loading, extracting and ejecting phases, the brass gets beat up, further stressing and potentially hardening it.
  • The powder’s burn rate has to be correct for a gas gun. Again, not just any rifle powder will do.
  • When you use gauges to determine actual cartridge OAL, remember that you must measure every bullet for each cartridge, because the bullets do vary substantially. And stay about 20-thousandths off the lands. Closer can be safe, but it offers no real-world accuracy improvement in gas guns.
  • Never assume “resized” brass is properly resized, and never assume new brass is properly sized. These often are not. Use your gauges to verify. Never assume your sizing dies properly size your cases, for often they do not, and often need to be adjusted as it comes from the factory. Gauge everything.

Every catastrophic rifle failure that has come into Fulton Armory can be associated with reloads. You’d think at least one would come in that blew up with factory or USGI ammo in 25 years.


The Mission of Cheaper Than Dirt!'s blog, The Shooter's Log, is to provide information—not opinions—to our customers and the shooting community. We want you, our readers, to be able to make informed decisions. The information provided here does not represent the views of Cheaper Than Dirt!

Comments (5)

  1. I have two AR gas operated rifles one 5.56 and one 308 cal.. I also have a Yogo AK-47 and would like to pass these weapons on to my kids.

    As years pass what parts should I be purchasing that you see will become quickly worn overtime? I shoot but don’t consider myself a active shooter.

    However, I would like to have the most common needed/worn parts down the road.

    However, I would like to have parts available down the road. Thanks!!

  2. I had Fulton Armory build me an AR-15 upper a few years ago to my specs, with their advice. I have never been so pleased with the quality and accuracy/performance of a rifle in my life. In short, their reputation is well-earned, and I highly recommend their services.

  3. nik: When you say hammer forged I’m pretty sure you’re confusing one of the best ways to make a barrel with normal forging.

    You’re right that the original M14 receivers were forged, and there are of course concerns about investment cast receivers. That said, decades of experience has shown us that good cast receivers can make good guns. If you insist on a semi-auto forged based M14, send them a Norinco receiver (which Clint praised back then they were more available) in good condition and they’ll build a rifle based on it. Otherwise you’re limited to rifles made with investment cast or the machined (not forged) Smith Enterprise receivers (there may be more options, I don’t pay attention since I have a high quality Armscorp receiver I bought back when G. H. W. Bush started banning assault rifle importation and the like in the late ’80s).

    Personal note: when living in the D.C. area I had them refurbish a M1 Garand, and can attest that they do *very* good work.

  4. Fulton armory is not the only company manufacturing receivers for M14/M1A.
    Moreover, original mil-spec receivers for M14 were hammer forged, Fulton armory uses investment casting.

Your email address will not be published. Required fields are marked *

Your discussions, feedback and comments are welcome here as long as they are relevant and insightful. Please be respectful of others. We reserve the right to edit as appropriate, delete profane, harassing, abusive and spam comments or posts, and block repeat offenders. All comments are held for moderation and will appear after approval.

Discover more from The Shooter's Log

Subscribe now to keep reading and get access to the full archive.

Continue reading