[snal]

So I finally shot my AR pistol this weekend. Had a few jams where the ejection didn't complete...jammed the spent round and halfway loaded the next.
I'm running a Larue FA BCG and a factory Spikes buffer and spring (factory built pistol lower) and a 8.5" bbl. Standard Remington L223R3 ammo.

BCG too heavy?
Spring too heavy?

 

[tsconver]

did you ask the upper maker what buffer they recommended for their barrel?

Have you shot it with one round to see if it locks open on empty? If it does not lock open it is probably too heavy of a buffer or too heavy of a spring. If it locks open after empty consistently you might need to upgrade to the heavier spring and o ring on the extractor.

 

[Phantom Crab]

I run a 10.5 inch DD upper. I also used the Spikes buffer and spring. I needed to go with a lighter buffer on mine and all was fixed.

 

[snal]

No I didn't.
Holds open on the last round.
Only shot 60 rounds through it as that was the last of my ammo...seemed to do better on the 3rd mag but I had no more ammo to run.
1st mag was the worst...probably jammed 4 times with it, less with the second, once with the third.

 

[shooter9949]

You might need a stiffer extractor spring like the Wolf: http://www.midwayusa.com/product/664713/wolff-extractor-spring-ar-15-extra-power

It's a common problem with AR pistols so I've heard. So common that I put one in mine before even test firing it.

ETA, I'm no expert. I'm just saying that based on the fact that the spent round isn't extracting AND it's common with the pistols. Could be the gas system too but the spring is so cheap you might as well try it.

 

[Wahoo95]

Who's upper is it?

What lube you using?

What mags?

AR's with barrels under 11.5" can be more finicky than their longer barreled cousins so you may need to tweak it to function correctly.

 

[snal]

Who's upper is it?

What lube you using?

What mags?

AR's with barrels under 11.5" can be more finicky than their longer barreled cousins so you may need to tweak it to function correctly.

Model 1 Upper

Rem Oil

Pmags

 

[Wahoo95]

Try some synthetic motor oil...10w30 for lube as Remoil isn't a good choice.

You may need to tweak it by playing with different buffers and springs as I'm not sure what Model 1 has going on with gas port specs and such.

 

[NCHornet]

I agree you may need to use the black o ring under the extractor, also examine the end of the extractor for any damage.

Let me also add that any small dents in the casings will come right out in the sizing die.

 

[Wahoo95]

I agree you may need to use the black o ring under the extractor, also examine the end of the extractor for any damage.

Great point! I seriously doubt M1S included an O ring under the extractor.

 

[snal]

Great point! I seriously doubt M1S included an O ring under the extractor.

The BCG is Larue

 

[Wahoo95]

The BCG is Larue

You did say that didn't you...LOL

 

[snal]

You did say that didn't you...LOL

I had to check to see if I did

 

[shooter9949]

I agree you may need to use the black o ring under the extractor, also examine the end of the extractor for any damage.

Let me also add that any small dents in the casings will come right out in the sizing die.

Again, this is just what I've heard, but the O-ring can deform and stop doing it's job. The stiffer spring is a longer lasting option for the same results.

 

[Shortfuze]

Model 1 Upper

Rem Oil

Pmags

Rem oil sucks I think it makes things rust.