I SBR’d a DPMS lower years ago before I knew better. Unfortunately it’s got a walking FCG pin problem. Obviously my next one will be a quality unit. I’m considering my 6920 lower, or my BCM. Hell, since I’ll have it forever, I might as well go all out and get another KAC lower or even an HK MR556.
Then there’s the question, should it be ambi or USGI stock configuration?
How do you guys decide on a lower? I’m just curious.
BCM…over …out.
Your walking FCG pin problem is generally not a function of the lower. It’s more likely a function of your trigger group. Replace those parts with quality stuff and you should be GTG.
BTDT, it’s the lower. The holes are oversized.
Try KNS pins yet? Sounds like it could solve your problem.
SBR your favorite lower. Once you get the stamp, you can put any upper with any length barrel you want on it, including the one you had on it originally. Once I had an SBR, I found that was what I shot almost all the time. I wanted it to be reliable.
I would really like to see this lower. Simply because I have seen lowers that were 20+ years old in the military that were used and abused and they worked just fine.
Unless the holes were drilled improperly from the start, like they probably were on mine.
I’ve tried fitting Colt and BCM LPKs in it, and they both have a noticeably looser fit than they do in their own lowers.
If you have the cash to drop on a KAC lower and want to spend it then go right ahead. Otherwise just do the Form 1 on your existing Colt or BCM.
I like factory SBRs. Have you considered a factory colt, BCM, or KAC sbr? Re: your current DPMS sbr, you can either use KNS non-rotating pins or consider sending it off to M60Joe to have the FCG holes drilled out and steel bushings installed.
I never knew you could do that. Not something I have needed but I have been worried about damaging the holes installing and uninstalling triggers.
When I get to it, it’'l probably only be a BCM, BAD, or Noveske (assuming there aren’t any quirks with mag compatibility for the gen IIIs). Definitely something nicer than a solid standard because it’ll probably be the one I shoot most at that point.
SBR a lower you really like. I SBRed a super low serial number of Umbrella Corps first run of lowers. It is a cool lower just because of the story itself, so I SBRed it.
It is a service I believe he offers mainly for transferable MG lowers with egged out FCG holes. Since these lowers are irreplaceable, they have to be repaired.
Thus far I’ve followed the instructions in the sticky thread. Put the lower together, slap my BCM 14.5 Middy upper on it and shoot the snot out of it. If it works correctly over a case or two of ammo, I consider it OK for NFA conversion.
Could it be that someone mod’d the receiver to take old Colt FCG pins?
Have you tried a set of .17 pins?
I’d get some KNS pins and be done.
There are very few bad lowers out there. I SBR’d a Superior Arms that is a little too snug in the mag well to take Gen 1 PMags. I don’t consider it the receivers fault, but Magpuls, and at least they got it right eventually.
I’d have no problem SBR’ing a non-gucci lower.
(That being said all my other SBR’d lowers are Noveske) 
Ive been looking for a good lower to SBR and a friend of mine sent me the CDNN deal on a POF Billet complete lower with POF trigger for 399.99. Purchased it and did the form 1 the same week. Waiting on it now…
I just pick the one that has the rollmark or selector options I like. Among my favs are:
But that’s the same reason I buy a lower in general. Like my JD Machine US Border Patrol lower (makes a nice build in FDE) and my Seekins lower (love the rollmark).
I SBR lowers that I want to pair with a barrel under 16 inches in length.
A couple of lowers that i like for SBRs: Mega Billet lower is very nice, so is the CMT billet stuff.
Last one i did was a Colt M4A1 Carbine lower but that was because of the gun i was building.