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TheKernel
April 9, 2010, 10:24 AM
I just got my AR-Pistol a few weeks ago, its an older spikes tactical but looks almost brand new. I tried to shoot it for the first time this week and it will not cycle a round after firing the first on from the magazine. I tried 4 different kinds of ammo and 3 different mags with the same results. The only ammo that would cycle the next round was tracer ammo. Any ideas on what the issue could be?? I dont want my ar-pistol to be a single shot!! :)

Thanks!

Brasky
April 9, 2010, 10:26 AM
did you clean the gas tube and/or the port in the gas block? Or are you saying it won't return to battery?

TheKernel
April 9, 2010, 10:36 AM
it was clean when i got it.. the guns is spotless and oiled. It returns to battery just fine, but it doesnt load another round.

Bartholomew Roberts
April 9, 2010, 10:45 AM
it was clean when i got it.. the guns is spotless and oiled. It returns to battery just fine, but it doesnt load another round.

Fire it with only one round loaded and see if it locks back on an empty magazine. That will tell us whether the bolt is not coming back far enough to catch another round or whether your magazine isn't feeding fast enough to put a round in place before the fast cycle time of the pistol AR bypasses it.

TheKernel
April 9, 2010, 11:02 AM
Thanks, i just dont know when im going to be able to shoot it again.

mchris80
April 9, 2010, 11:12 AM
I had that problem with my AR at one point when it was new. It ended up being a broken carrier key screw. I noticed it was loose and realized it was broken when I tried to tighten it. Worth checking.

tirod
April 10, 2010, 08:13 AM
What kind of ammo, and how many in the magazine?

Low powered white box fodder sometimes won't cycle. Fully loaded mags can have high spring pressures fully stacked. Many are older, have lots of interior friction, don't have good followers, have bad feed lips, and could have a incorrectly cut mag retainer hole that puts it at the wrong height.

And what caliber is it?

TheKernel
April 10, 2010, 11:16 AM
Its a 5.56/.223 I was loading twenty rounds into the 30rnd mags. I know these mags work as I have shot them all from my previous AR. I tried Lake City, Brown Bear, American Eagle, and some tracer ammo that im not sure what brand it was.. the tracer ammo was the only ones that would cycle another round.

rjrivero
April 10, 2010, 11:22 AM
It sounds as if this is a gas system or buffer system issue.

Inspect the gas key on the carrier. Make sure it's tight and properly staked. Look at the gas tube itself. Make sure the gas tube isn't cracked. Look for signs of gas leaking from the tube a the gas block. If that looks okay, then look at the rings on the bolt. Make sure they don't "slide freely" they should have a bit of resistance to them.

If the gas system looks okay, then you need to look at the buffer and buffer spring.

If you're using a buffer that's too heavy then you could cause short stroking. The usual buffer for a 7.5" pistol would be an H2 or similar buffer. You can try a carbine buffer or a standard buffer. If that doesn't fix the issue the only place left to look is the gas port on the barrel. You'll need to measure the port size and open it if it's too small.

11.5" barrel, .625: dia., 3.850" from muzzle;
Port sizes from .081" to .089"
11.5" barrel, .750" dia., 3.850" from muzzle
Port sizes from .086" to .094"

14" barrel, .625" dia., 8.375" from muzzle;
Port sizes from .063" to .078"
14" barrel, .750 dia., 8.375" from muzzle;
Port sizes from .070" to .086"

16" barrel, .625" dia., 8.375" from muzzle;
Port sizes from .063" to 078"
16" barrel, .750" dia., 8.375" from muzzle;
Port sizes from .070" to .086"

20" barrel, .625" dia., 8.375" from muzzle;
Port sizes from .086" to .093"
20" barrel, .750" dia., 6.875" from muzzle;
Port sizes from .093" to .096"
24" barrel, .825" dia.,
Port size .089"

Scorch
April 10, 2010, 12:00 PM
I know this is a radical idea, but have you tried calling the manufacturer? They might want to service it, or might have some input.

TheKernel
April 10, 2010, 12:12 PM
I havent called them yet.. but they are 20 minutes from where i love so i could just drive it over there and see what they have to say..

Bartholomew Roberts
April 11, 2010, 03:53 AM
Its a 5.56/.223 I was loading twenty rounds into the 30rnd mags. I know these mags work as I have shot them all from my previous AR.

They may work with your other AR because it has a lower cyclic rate due to a longer gas system. The longer gas system gives the magazine a few more microseconds to push the next round into position. When mags are marginal, they will work in a rifle length system; but not a carbine length system for example. A pistol AR has a really short gas system and the magazines have to be perfect or you are going to have problems.

You still need to shoot it to determine the problem; but the problem is likely either in your gas system (not enough gas to cycle the action - either because buffer/spring is too heavy or because the pistol isn't getting enough gas (ammo, port too small, loose gas key, bad gas rings, etc.)) or it is the magazines.