AR Pistol, double feed, ftf causes?

[chomorro]

I have two 5.56 builds, different parts and setups on each. One runs flawlessly. The other gets these jams as shown in the picture with same mags and ammo.

Is this a feed ramp issue? Or buffer, spring issue?

M4 feed ramps do not line up perfectly with the barrel on this setup but work 90% of the time.

Sent from my SM-N950U using Tapatalk

[coy80176]

Taking a guess...

If your pistol barrel is < 10" it may be over gassed.

How long is the barrel?

[chomorro]

If your pistol barrel is < 10" it may be over gassed.



How long is the barrel?

10.5" barrel with a low profile non adjustable SI gas block

Sent from my SM-N950U using Tapatalk

[chomorro]

If your pistol barrel is < 10" it may be over gassed.



How long is the barrel?

Here is the feed ramp of the black working one and tan ftf one.

Sent from my SM-N950U using Tapatalk

[SmallShark]

i would manually pull and release the charging handle to test it with dummy rounds

the barrel looks fine to me. try different mags, load 2-3 rounds only

[Frank1911]

I had the same thing happen to me. I cleaned it, polished my ramps, changed my buffer spring, & buffer, tried different ammo, etc. and finally found the culprit. It was my gas rings. They sure do take a beating in these short barrels. After installing the one piece gas ring, never had another problem.

Keep us posted and good luck!

Sent from my SM-G930V using Tapatalk

[chomorro]

I had the same thing happen to me. I cleaned it, polished my ramps, changed my buffer spring, & buffer, tried different ammo, etc. and finally found the culprit. It was my gas rings. They sure do take a beating in these short barrels. After installing the one piece gas ring, never had another problem.

Keep us posted and good luck!

Sent from my SM-G930V using Tapatalk

Didnt think that would be it since the build only has a few hundred rounds through it but I will do the test I found on YouTube to see if they are bad. Thanks!

Sent from my SM-N950U using Tapatalk

[Frank1911]

Yes, do the bolt test but take a visual look at the rings to see if any of them are broken. Shouldn't take more than a minute or two.

Sent from my SM-G930V using Tapatalk