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12/24/2002 8:26:34 PM EDT
What am I doing wrong.  I just assembled two lowers (one BM, one Hesse kevlar) with DPMS lower parts kits.  I was unable to get the trigger guard roll pin to flush up with the lower.  When I did the Hesse first, I thought it was just the lower.  But the BM was just as bad. Is there a trick to this that I'm missing.  This is my third lower, and my first Oly was assembled using DPMS parts and I was finally able to get it flush after alot of work. John
PS Merry Xmas
12/25/2002 3:09:37 AM EDT
[#1]
Sounds like the punch you are using may be flaring the roll pin to the point that the last fraction of it will not enter the hole. Try using a "roll pin punch"* of the correct size, or lacking that, a plastic or nylon punch to drive the pins in. And as you've probably figured out already, make sure the under side of the lower is supported so it is not moving about while you drive the pins in.

* A punch made specifically for installing those roll pins - available from most better tool suppliers.
12/25/2002 5:43:43 AM EDT
[#2]
I am using roll pin punches, and originally didn't have good support, but even after supporting everything, they still don't want to sink.
12/25/2002 7:43:57 AM EDT
[#3]
Hmmm...Are the pins hanging up when leaving the triggerguard and attempting to re-enter the lower? Or simply lacking that last fraction of an inch to look fully seated?

BTW, I always bevel (slightly) the insertion end of a roll pin. Seems to help get it started and keep it from hanging up on any part's edge as it goes through the holes.
12/25/2002 10:26:40 AM EDT
[#4]
It appears to be binding just before entering the opposite side of the lower.  Almost like its hung in the trigger guard itself.
12/27/2002 5:17:33 AM EDT
[#5]
http://www.ar15.com/forums/topic.html?b=3&f=4&t=146064

Another post on this same topic (with disheartening results). Before driving those pins though the lower and trigger guard try inserting a slave pin that is slightly smaller in diameter than the roll pin to make D$#% sure every thing lines up. If the holes through the trigger guard and the lower are not aligned (probably because the trigger guard hole is not drilled perpendicular to the guard) then that roll pin is going to be pushed out of line and will hit the lower tab as it exits the guard. Adjust the trigger guard hole if necessary (i.e., ream it out straight) and bevel the end of that roll pin!

1/1/2003 5:25:00 AM EDT
[#6]
Guys here recommended flexing the roll pin before inserting and mine went in without a hitch and is flush. Forged DPMS.
1/1/2003 6:04:36 AM EDT
[#7]
Do like GunCat said, bevel the pin end, lube the hole and pin w/ a little grease, and be very sure it is supported properly, i have done two with no problems, but I am SURE you could break them easily if they are not supported well.

Rancid Lance
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