I bought one of the Palmetto State Armory premium bolt carrier groups recently. I put it in a 16" mid-length to test it. This rifle borders on the under gassed historically. When the rifle was brand new (with a DS Arms BCG), it would short stroke and fail to lock back with Tula. It grew out of this to the point where it ran Tula and other steel case (Barnaul) pretty well, with rare short strokes and locking back most of the time. While testing the new PSA BCG today with Monarch steel case (made by Barnaul), it would never lock back and would short stroke about 20% of the time. It ran Hornady Superperformance Match just fine. I do not see any signs of defects in the PSA BCG.

Is it typical to take some time to break in a new BCG before getting optimum performance from it or should I be concerned with the PSA BCG?

The finish could wear a bit smoother. What upper is it that you're running? I know you mentioned the DSG BCG - is it one of their Seekins/DSG uppers? There have been a lot of reports about the gas block coming loose, moving a bit, and causing the problem you're having. If the rifle wasn't running 100% before, I don't think I'd blame the BCG for anything.

lube it up and use some M855 and some M193 ball ammo then report back on how it runs.

Did you lube it a lot?

^^^Yeah, that's a big one...I have one of these and it needs to be field stripped and lubed like crazy...comes dry as a bone.

The BCG was thoroughly cleaned and generously lubed prior to use. The extractor spring and pin did come loose while I was cleaning. It went back into its hole a little cock-eyed. I doubt that has anything to do with the short-stroking, though.

Sounds like a gas issue. I would check the gas block to ensure it is seated correctly. Are you using a heavy buffer or a standard carbine buffer?

It's a standard carbine buffer. The rifle was working fine with the old BCG. (I consider occasional failure to lock back with Tula normal function.) Putting a new BCG in didn't loosen the gas block or change anything other than the BCG. If the rifle's function diminishes immediately after changing only the BCG, you can safely bet the thing that caused the diminished performance is the BCG. My question is whether I can expect improved performance from the BCG with use or whether I ought to contact PSA because their BCG short strokes ammo that a DS Arms will cycle.

Are both of these carriers full- or semi-auto profile? Did something happen to the original bcg to need a replacement? PSA has been known for canted front sites/gas blocks. That would cause your cycling issue. All new parts will break in with use, but as you already know, there has been something off since day one. Blocked gas flow, gas leak, or the carrier and/or buffer are too heavy.