The AI PSR may have only been available in limited quantities but the only differentiators when compared to an AXMC is the finish/cerakote (IR Reducing?) and "PSR" serial number prefix. (someone please correct me if there's something else, but I think that's it). While it would be really cool to have, the value just isn't there for me to seek a PSR and when I can have 99% of the base rifle it in a run of the mill AXMC.
RemDef MSR/PSR deployment kit was also extremely limited in its release. I'm not sure of the actual number but I'm sure it's not far off of the AI PSR figure. I've seen about the same number of each for sale in the past 5 years or so.
MSR/PSR: The bolt heads and barrel extensions pop up rarely or are passed around in certain circles. I'll be buying the next ones that I see or hear of for sale. The firing pin in the MSR/PSR is unique to that action. Additionally it's made from an exotic metal with a unique heat treatment.
@AIAW has a dedicated thread on a few of the road blocks most MSR/PSR people experience
HERE. I've never seen an MSR/PSR firing pin for sale, however, the deployment kit (sounds like you found one) will come with an extra firing pin assembly. This is the only reason I own the kit I do now. Not sure I would've been willing to acquire it without that piece.
AI pic tax:
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