It seems like every CORE15 AR15 I have seen at the range has jammed at some point while I was watching owner use it. I don’t have the evidence to say damning things about the company, but I haven’t seen anything that would let me say good things about them. A sample size of a half dozen isn’t good, but seeing a half dozen that appear to have issues isn’t comforting.
I have helped a few shooters clear squib loads recently.
When ever you fire a shot that has reduced recoil, or an “inaudible pop” it is good to check to see if your round has actually left the bore. Firing another round after a squib can have disastrous consequences. Replacing a barrel is not cheap, however being injured by an exploding firearm can be even more expensive.
Case head separations are usually rare, but I have been seeing more of them, and reading about them more. Perhaps due to the last ammo panic people are trying to get more uses out of each case.
Spending a few dollars on a broken shell extractor may be well worth while.
High recoiling firearms can be punishing. Nearly every day at the range we over hear someone complain about firing shotguns or Mosins. Sometimes the recoil causes other issues. People can drop a firearm after a surprising amount of recoil, and that recoil can break things. For example this S&W scope mount came off a S&W .460. The resulting flying scope hit the owner on his head and dented the Leupold.
The owner explained that previously he was having issues with the screws in the scope rings breaking. I keep thinking that if that recoil is breaking screws, what it must be doing to the owner of the firearm.