Advise last part needed for AR9

[uffdaphil]

I have the factory 16" PSA upper, a stripped PSA Glock lower and build parts. The only question left is will a standard carbine spring work with my 8.5 oz Q buffer or do I need to buy an extra power? Somewhere I got the impression the stronger spring was more a short barrel requirement.

[misfit47]

I ran a standard carbine spring with no issues

[uffdaphil]

Thanks. Now that I have it done, I'm not that excited about it. Might just sell it and put the cash towards a Scorpon SBR when/if they become available.

[misfit47]

Same conclusion I came to after building mine.

[uffdaphil]

One further question. Did your bolt lock back with the charging handle? My BCG withdraws almost 1/4" too short to catch. If so it seems odd to even have a bolt catch installed.

[misfit47]

Is your buffer longer than the standard buffer? Mine was a kit and worked like a clock.

[uffdaphil]

Thanks. That was it. I had the heavy, longer Q buffer in it. What weight regular sized worked for you? Is it special to the 9mm or can I use one of my spares. PSA is out of stock and no specs listed.

[misfit47]

It was heavy one. H3 I think. I'll see if I can dig up the specs. H3 it was.

[uffdaphil]

But just a standard AR 15 buffer, right? I have most weights up to H3.

[misfit47]

Yup. Just heavier than standard. Think it's 5.6oz.