Acurracy issue/possible chamber problem

[P2000]

I'm interested to see pictures of the freebore / throat through your new borescope (maybe I want one).
Wondering if a good scrubbing with a brush will clear this up.

Also wondering if you remove the bullet from the cartridge then place cartridge in chamber, will the BCG lock easily and extract easily? Through all the Q and A, it seems the answer would certainly be yes, but this would verify some things.

[tehpwnag3]

Any velocity data?

Could it be that the light-weight varmint bullet is thin-skinned and being pushed too fast out of that 1:7?

[stank]

I'm interested to see pictures of the freebore / throat through your new borescope (maybe I want one).
Wondering if a good scrubbing with a brush will clear this up.

Also wondering if you remove the bullet from the cartridge then place cartridge in chamber, will the BCG lock easily and extract easily? Through all the Q and A, it seems the answer would certainly be yes, but this would verify some things.

I only have a cheapo endo scope so I still have yet to locate a proper borescope. Empty cases chamberd and extracted fine. If I seated bullet in empty case super long and dropped it in the chamber then ran the bolt home the barrel would hold onto the bullet and the case would come out with bullet still in barrel. It could be possible it was butting into the rifling but bullet only showed scratch marks and not rifling grooves. I tried the same thing in another rifle and it would eject both bullet and case with no issue. It passed a field and go gauge. I have scrubbed it quite a bit so far and will probably clean it some more now it's been pulled. For the time being I am using a spare barrel I had laying around.
Velocity was around 2900 fps if I remember correctly with s 55 grain Vmax. I still believe I had something come off the tip of a case or some other debris and lodged in the chamber lead/freebore area and then was fired into barrel making removal difficult without special tools. I also believe it possibly cause excessive lead buildup in bore due to cutting jackets as it left the case. Time for me to find an AR specific gunsmith and have it checked out. Now I have the rifle back up and running the urgency level is down, but I am damn curious what happened.

Sent from my Moto G (4) using Tapatalk

[P2000]

I only have a cheapo endo scope so I still have yet to locate a proper borescope. Empty cases chamberd and extracted fine. If I seated bullet in empty case super long and dropped it in the chamber then ran the bolt home the barrel would hold onto the bullet and the case would come out with bullet still in barrel. It could be possible it was butting into the rifling but bullet only showed scratch marks and not rifling grooves. I tried the same thing in another rifle and it would eject both bullet and case with no issue. It passed a field and go gauge. I have scrubbed it quite a bit so far and will probably clean it some more now it's been pulled. For the time being I am using a spare barrel I had laying around.
Velocity was around 2900 fps if I remember correctly with s 55 grain Vmax. I still believe I had something come off the tip of a case or some other debris and lodged in the chamber lead/freebore area and then was fired into barrel making removal difficult without special tools. I also believe it possibly cause excessive lead buildup in bore due to cutting jackets as it left the case. Time for me to find an AR specific gunsmith and have it checked out. Now I have the rifle back up and running the urgency level is down, but I am damn curious what happened.

Sent from my Moto G (4) using Tapatalk

It is a weird situation. I'm curious as well. Neck separation that got perfectly lodged in there? At this point it might be easiest and possibly cheapest to trash the barrel and move on. But that would leave the mystery unsolved.