Parts for SR-762 builds

[eunichron]

Hey all. So, I'm not new to this forum, been coming here for over a decade, but I suppose there was a backend change at some point and lost my account. Anyway...

I (maybe stupidly) jumped on Primary Arms' recent deal on stripped SR-762 lowers. Bought a pair of them for some builds I've had in mind. I'm no stranger to building large frame ARs, and thought it wouldn't be too difficult to find parts to finish the receivers and find matching uppers even with the rifles being out of production for several years.

My hope was to find some Ruger or AR10A small parts to do some further test fitting to see what sticks... Numrich has a decent amount of Ruger small parts, but no takedown pins in stock. I reached out to Ruger but have not received a response yet. No dice on any Armalite small parts A or B series.

Down to brass tacks... I'm looking for a source on these parts in order to finish the receivers and build a couple rifles:

• Small parts in general, but especially pivot and takedown pins, including springs - the takedown detent spring is longer on the Ruger since it is installed through the rear of the receiver.
• Bolt catch - as best I can tell an AR10A bolt catch should fit
• Upper receiver with DPMS threads - I've looked at the Centurion Mk11 and HTX Concepts SR25. Both look promising. I know the likelihood of them using the same pin size is next to nil.

Thanks.

[eunichron]

Centurion got back to me and confirmed their Mk11 upper will not mate with the SR-762 lower. He did lead me on to the Stag10 upper, which I've seen mentioned in other forums, but no confirmations that it does mate with the SR-762. Looks like OpticsPlanet has a few Stag10 uppers in stock, might pick one up for some test fitting.

Edited 4 hours ago by eunichron
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