Colt Upper Compatibility Question

[JawBone]

For the Colt Gurus:

I have a pre-ban (circa 1989-1990) Colt Upper 20" and I am putting together a new OLL for her.

The upper has a large front pivot hole, so I know I need to get the "reverse offset pin" from Bushmaster to attach it to a new OLL.

My question is whether I also need to get the large diameter hammer and trigger pins, or will a "normal" (stag/rra) lower parts kit work with the Colt Upper?

Thank you in advance for any info.

[tiger222]

the trigger & hammer pin size are a seperate issue from the upper compatability ~ use the HTS that fits the lower and you are good to go!

[mike452]

If you have a large front pivot hole, I would think you will need a lower parts kit with the .169" large pins. Standard LPK will not work.

http://www.rbprecision.com had the large pin RRA lower parts kit last year.
Or replace the pins on your own.


OKAy.. I was confused.. Ignore what I said..

[ocabj]

If you have a large front pivot hole, I would think you will need a lower parts kit with the .169" large pins. Standard LPK will not work.

http://www.rbprecision.com had the large pin RRA lower parts kit last year.
Or replace the pins on your own.

The OP has a large pin Colt upper.

If you're buying a new lower which is an OLL, 99.9% it's going to use a standard lower parts kit. The lower parts kit doesn't know what upper you have.

Example of a lower that requires the larger hammer and trigger pins:

[stevie]

All of the OLL's currently available (Stag, Double Star, Spikes etc) will use the standard (small) pin LPK. The large hole Colt upper has no bearing which lower parts kit you will required. The OLL will govern which LPK (large/small pin) is required.

[JawBone]

Makes sense. Much appreciated.

[SemiAutoSam]

Not all but most.

All of the OLL's currently available (Stag, Double Star, Spikes etc) will use the standard (small) pin LPK. The large hole Colt upper has no bearing which lower parts kit you will required. The OLL will govern which LPK (large/small pin) is required.