Colt Large pivot pin upper to new lower

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[ARCHIVED THREAD] - Colt Large pivot pin upper to new lower

Posted: 10/6/2004 12:15:17 PM EDT

I have a mid-1980 Colt Sporter HBAR. Used its lower receiver to mount my M4 upper on.
Can I mount the HBAR upper (large pivot pin) to a new lower with the smaller pivot pin hole?
If so , what do I need to do it.
Thankshinking.gif

Posted: 10/6/2004 12:26:48 PM EDT

[#1]

Here

Never have tried one, but here is one option I know of.

Danny

Posted: 10/6/2004 12:31:29 PM EDT

[#2]

you need those conversion pivot pins, I heard they're a pain to use though.

Posted: 10/6/2004 11:19:27 PM EDT

[#3]

For a large hole upper, all you need is an offset bushing that costs $3.00. You can get it from Al's Custom or DPMS. DPMS presently has free shipping on all online orders.

Posted: 10/7/2004 4:52:14 AM EDT

[#4]

Quoted:
I have a mid-1980 Colt Sporter HBAR. Used its lower receiver to mount my M4 upper on.
Can I mount the HBAR upper (large pivot pin) to a new lower with the smaller pivot pin hole?
If so , what do I need to do it.
Thanks

got a friend with a lathe ?? i make two bushings from hard brass O.D. is .312" actually i make them .316 so they fit snug & do not fall out (5/16th inch) then drill out .250" (1/4 inch) hole & assemble with small pin.

Posted: 10/7/2004 10:10:18 AM EDT

[#5]

Many thanks

Posted: 10/7/2004 5:24:41 PM EDT

[#6]

Dont spend too much money.... you could get close to the cost of a new *in spec* upper... and be done with it.

Posted: 10/8/2004 8:59:48 AM EDT

[#7]

Quoted:
Quoted:
I have a mid-1980 Colt Sporter HBAR. Used its lower receiver to mount my M4 upper on.
Can I mount the HBAR upper (large pivot pin) to a new lower with the smaller pivot pin hole?
If so , what do I need to do it.
Thanks

got a friend with a lathe ?? i make two bushings from hard brass O.D. is .312" actually i make them .316 so they fit snug & do not fall out (5/16th inch) then drill out .250" (1/4 inch) hole & assemble with small pin.

Lowes and Tractor Supply offer 5/16" bronze bushings about 1" long with a 1/4" hole in them. I got one and cut to length with my Dremel. It fit right in the upper. The bushing IMO needs to have the hole offset slightly for the upper to close all the way (mine was tight, didn't want to force it).

Danny

[ARCHIVED THREAD] - Colt Large pivot pin upper to new lower

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