Little things to increase an ARs' reliability

Trajectory

johnwill, while you are correct that gravity is always pulling down on the bullet, you could not be more incorrect in saying it never rises after leaving the barrel, at least with reference to the horizontal plane. To prove the point with an extreme example, aim the gun at a 45 degree angle from the horizontal. Obviously the bullet "rises" from the horizontal plane.

You are likely thinking of a bullet fired with the barrel parallel to the ground, or angled downward. In those cases, the bullet will indeed start moving downward upon leaving the barrel.

But remember that the sights are above the bore, so the bullet necessarily starts below the line of sight. If we didn't shoot upward from the bore line, we'd never hit what we were aiming at, since the line of sight is always above the bore line. The sights are set so when the bullet is fired, it _rises_ above the line of sight, starts falling after achieving maximum trajectory, and returns to the line of sight at some point further.

If we take a rifle sighted for, say, 300 yards, the bullet indeed rises to intersect the line of sight some distance away from the muzzle (roughly 50 yards), and arcs to cross back down to the point of impact (300 yards).
 
Badger, why is it bad?

All gas-operated arms have to do it so why not minimize the weight of the operating parts? For one thing, the op-rod will never bend on the AR. Sure the gas tube can bend but its well-protected under the hand guards.

All of the improvements have made the 0-300 meter rifle good out to 550 meters on point targets and up to 800 on area targets. Sure the burst feature limits its use as a area target weapon but it can and will reach to this distance.

FWIW, the forward assist is a tactical issue and the AF declined its use for SP/MP use. Army and USMC need it for silent (nearly) charging.

Reliability tips? Quality rifle and quality ammo.
Clean every 400 rounds (yes, I've gone to 600 w/o malfunction)and keep it buttoned up when not shooting.

Improvements? How about a magwell boot to keep crud out? Ditto for the mag base. And the bolt stop opening. Reverse the spring on the dust cover so it auto closes instead of opening.


Its a great rifle.
 
Keith:

It's really telling how posts by the Stonerphiles out there tend to contradict themselves. I'm not sure you even realize it, but you did the same thing. For one thing, you say how the forward assist is necessary for silent closing but then ask for an improvement in keeping gunk from getting in through the mag well. Why is gunk a bad thing? This is typical M-16 thinking that has us believe EVERY gun has to be kept clean to operate. This comes from being conditioned on rifles like the M-16 without ever having experienced the beauty of a properly designed battle rifle chewing up cases of ammunition without the need for a cleaning. The AK-47 doesn't mind. My SKS doesn't mind. Mini-14 chews it up. The FAL, Galil, HK G36, G3, Garand, Carbine, Sig 551, etc, etc, ALL eat up debris without problems. The problem is that the AR-15 is NOT as battle-reliable as ANY of the guns above.

As for the OP rod, you said it was easier to bend, BUT you knocked op-rod designes because they might bend? On the AK, AR-18, and G36, the Operating Rod is always protected and I don't hear about problems with them!

As for the gas venting into the bolt, THE M-16 IS THE ONLY RIFLE OF THE ABOVE MENTIONED THAT VENTS OPERATING GAS INTO THE BOLT. Keith, do you understand what we mean when we say that? Not sure how you can stand by your assertion that all rifles do this. The operating gas for any of the piston guns mentioned dumps into the gas port/piston area which is (more or less) self-cleaning. The HK G3 doesn't do this, but still gets dirty.
 
Regarding AR reliability. I've fired most all the above posts rifles and experienced various jams and failures. After years of shooting my ARs I've had ONE that stovepiped regularly and a pistol variant that we never did manage to make run quite right. My others have been essentially failure free. And I have NEVER been one to do a great deal of cleaning. Point being I fail to see any great difference between any of the rifles in question regarding reliability. They are ALL good stuff. It's all just a question of personal preference and bias.

And about bullet "rise". There is no such thing. Hold the barrel level and the bullet begins to drop as soon as fired. Lift the muzzle for a longer shot and you get ARC, not rise. People got this odd idea about bullet rise from illustrations attempting to demonstrate the elevated placement of the muzzle, thus the "lift" shown in these illustrations. American Rifleman had a write up on this recently, I think in the January edition.
 
Why is gas dirty?

Or more importantly, why is the M16 design bad? The gas is vented in between the back of the bolt and the forward portion of the carrier. Nothing complex there to foul up. Matter of fact, the gas desposits build up only to a certain level and then stay constant. Cleaning here only causes wear. Dirt actually HELPS as it reduces the metal to metal contact at the rear of the bolt. This is a gas-sealing area which likes to run dirty.

As far as cleaning, it was NOT the M16 which duped the services into overcleaning. Matter of fact, once the "teething problem" due to inferior Ball (tm) powder was resolved, less cleaning was required than any other service rifle. 5.56 was the first cartridge introduced into US service that was never loaded the corrosive priming. And there is the key.....Before Pb-Styphanate priming, perchlorate priming was the norm. Its use left a thin layer of potassium chloride (KClO4 decomposes to KCl + 2 02)which being a neutral salt, promoted corrosion. This salt is held in conjunction with carbon, graphite etc from firing and removal of the dirt meant the KCl was gone and the rifle would be resonably protected. Hence, the "white glove" test arose.

Op rods are well protected but can bend from a hot round or higher than normal pressures. The M16 handles hot ammo just fine and even functions on very weak ammo. No gas regulator is required.

I will admit the M16 family requires tighter tolerances on some parts but is that a bad design?
 
Sorry if this is too rude...

But couldn't a gas tube feeding a short-stroke piston that whacks the bolt carrier blend the best of the gas tube and op rod worlds?

It couldn't be more than 2-3 ounces more than the simple "tube gunks up the works" system.

Designed properly, it could also be self-regulating. I'm NOT convinced that the vaunted FAL multi-position gas port is really the best answer. Anything that can be SET, can be set WRONG, sometimes with results far more disastrous than the last time someone screwed with your sights.

Still sounds to me like the AR system has some design-related reliability problems that cannot be blamed on the flimsy magazines (another design problem I've fought with--cured by the Or-Light magazine??? Never handled one.)

I hear denial in this thread, and I'm not talking about a river in Egypt. Most may plug along fine, but the misbehaving samples are most troublesome.
 
Design......

The gas system in the M16 was designed to limit impact stress to the aluminum receiver to that caused by the buffer contacting the end of the tube. The bolt is comfortably nested in the steel receiver extension with the carrier free to move aginst the buffer and spring.

I'm sure a system could be kludged into the M16 receiver but is the gas system the weak link? I have only heard of the very first ammo lots causing any problem and that was due to recycled powder with excessive calcium carbonate levels. Gas tubes don't clog (velocity is too high) and the crud that builds up in the bolt/carrier does not affect functioning.

Magazines and non-ammo related dirt are the two big problems with the M16. Back in my service days, FTF's were induced by placing dummy rounds in the magazine! I never had a "real" FTF, only simulated. With blanks, a different story but then again so do all other autos.

Sure there is a little crud that builds up in the front of the bolt but its a soft kind of crud and is easily displaced.

BTW, I've fired over 10k rounds out of various M16's and AR15's with the only FTF's in brand-new parts rifles or ones with improper "basement gunsmithing" repairs. I had one malfunction that was ammo related but it was due to a American Eagle reload (very bad juju). Compared to my M1 carbine experience, the M16 shines. Compared to my M1 Garand experience, the M16 is far easier to shoot. Compared to my AK/SKS expereince, the M16 outshoots either and is faster to recover.
 
Again, I'll qualify my previous statements by saying that I have two AR-15's and think they handle great, are easy and quick to operate, and are more accurate than any of my other guns save two particularly good bolt guns I have. The basis for this thread was increasing the reliability of the AR type weopons. The way to do that would be to use an AK-47 style piston-attached-to-carrier style of gas operation. This would do nothing to the 'metal contacting metal' type of operation principle, would eliminate the gas-rings failures, and would preclude any fouling going into the action from the gas system.

As for propellant gas not creating solid fouling, that's bunk. Ever look at the muzzle and cylinder of your revolver after firing? Lots of solids and fouling there.

There is a reason I own the AR-15, I like it. I'd like it better if the design flaws were corrected. Had several FTF with three of the AR-15 style guns I've had over the years. One was an AR-10 with a tight chamber and a quirky mag. Another was an ammo problem (funny, my mini-14 ate them up). A third gun had two unexplained FTF's with factory ammo that cleared up after I cleaned the gun.
 
You must log in or register to reply here.
Back
Top