Ok, I admit it, I have a problem.  I can't stop buying AR's. I guess that puts me in pretty good company.

Anyway, this time I want to build my own (first timer).  I think I'm going to start with one of Pete's Rock River Arms "US Property" stripped lowers. That leads to my question - Who makes the best lower parts kits?  I'm mainly concerned about quality here, although price is always an issue.  Am I better off buying a RRA parts kit (to ensure compatibility), or are they all pretty much the same?

If anyone has any first-hand experience with RRA lowers, please share your insights.

I'd appreciate any suggestions.  Thanks

1) I like Armalite buffer tubes over Bushmaster because the Armalites are a) black and b) are reinforced at the neck and so reduce or eliminate stock movement at that point as well as providing greater strength (theoretically benefical).  Note: An ARFX stock will not fit over an Armalite buffer tube.

2) I also like Armalite roll pins over Bushmasters because they are a) already tapered at the ends and b) are more round.

3) I like aluminum trigger guards over the plastic kind Bushmaster sells.  You can get an aluminum trigger guard from... guess who.

4) For all other lower parts I have found Bushmaster's to be superior, even if in only small and subtle ways. (I am a perfectionist)

5) I like the tighter upper/lower fit with RRA receivers, but don't care for the tighter mag well when using my Thermold mags -- most won't drop free.

6) RRA lowers have slightly thinner dimensions in some areas.  For example: mag wall thickness, overall width.

7) You will get a better finish -- smoother and blacker -- with RRA as opposed to Bushmaster.

Best wishes on your project!  Building is a blast!

I don't have a problem with RRA or Bushmaster but if they shipped me a plastic trigger guard it would go right back.

I usually buy parts from pmswebstore.com

Paulson's Military supplies (just $60 lower completion kits and bolt carriers the rest is over priced.) He only sells milspec parts and that includes only milspec aluminum trigger guards.

Legal Transfers (AKA Pete-in-NH) also carries and sells RRA lower parts kits for I think $55, and mine was perfect in an Eagle Arms lower.

If you're getting the lower from Pete, might as well add the lower parts to the order and save shipping.  I also like his "enhanced" bolt carriers-- complete lower set and bolt/carrier was $175 shipped.

Cheers, Otto

The RRA two-stage Match trigger has a real nice feel for long range shooting.  I have one Bushy and one RRA and both have a similar feel with a very crisp let off.  Not quite a Jewell but not $250 either.

My RRA lower is slightly more shallow behind the trigger group and my Bushy uppers won't close properly with it.  There's been some discussion of compatibility problems, but RRA and Fulton Arms uppers work fine.

I agree with Otto, if you are already getting a lower from Pete just get the parts kit from him too to save on shipping.  I've built lowers with RRA and DPMS lower parts kit and found the quality of both to be excellent.