I bought a PSA 16" upper in January. Have not shot my gun much. But when I do get out to shoot it it has failure to feed issues. I think that the feed ramps are cut a bit to sharply.
Has a PSA 16" upper, Noveske N4 chainsaw lower, PSA LPK, and only used USGI mags some are Okay and some are Colt mags.e
Feeding from one side
Feeding from the other
Overall view of both ramps
DPMS upper. I noticed the feed ramps look much different on this upper and it feed rounds great.
Scratches on the bullet
Any ideas on how to fix this issue? I dont want to send it back to PSA, but will if I must.
Did the sand paper thing. So far it seems to have worked. Only shot 20 rounds though. Ammo is too expensive and rare around here yet to give it a real test.
Looking at your photos, I can see that the tips of the rounds are hitting the front of the magazine.
When you load your magazines, the rounds should be loaded so they are in contact with the rear of the magazine. This should put the tips clear of the front of the magazine when feeding, and there should not be scrape marks on the front of the magazine.
If the rounds are touching the front and rear of the magazine at the same time, the rounds are too long (out of spec), or the magazine is too short out of spec).
The heavy marking from contact with the bullet tips on so low on the ramps on the barrel extension is not normal. This may be an indication of another problem, possibly a bad magazine. This will exaggerate any break-in problem that you may be experiencing due to machining burrs on the feedramps.
I always give the mag a good hit at the rear every 4-5 rounds to seat them to the rear of the mag. I will lookout for an out of spec mag. All ammo I have fired has been factory PMC or Federal.