Colt AR upper question

[Sam]

I'm not up to date on Colt ARs so here goes the question. A friend of mine has a Colt AR with 16" barrel on an A2 upper. He wants to get a flat top upper with a heavier profile barrel. I understand that the Colt upper front take down pin is different from other makers. So to use another upper, let's say an LMT, does he need one of those "offset" pin? I'm not sure if that's the correct term or not.
Thanks.

[Alaskapopo]

On new colts the front take down pin is the same. A while ago colt used a large take down pin in the front. But even if that were the case there is an adapter pin sold through Bushmaster.
Pat

[Sam]

This is an older Colt, maybe 10 years old or more.

[Alaskapopo]

This is an older Colt, maybe 10 years old or more.

Not sure you will have to take some calipers to the front pin.
Pat

[akviper]

Does the front pivot have a regular slide out pin or is it a captured double headed screw set up? The latter will require an adapter to use mil-spec uppers. The adapters are easy to find and not expensive if you need one.

[avmech]

Or just buy a large pin flat top upper receiver from Daniels Defense......http://www.danieldefense.com/?page=s...&product_id=19

[5pins]

Does the front pivot have a regular slide out pin or is it a captured double headed screw set up? The latter will require an adapter to use mil-spec uppers. The adapters are easy to find and not expensive if you need one.

Not necessarily true. My Colt I got 8 years ago had the screw pivot and is the newer size. If your pivot pin if it’s .250 it’s GTG and will fit standard AR uppers.

[platypusREX]

If the pin need two screw drivers to unscrew it then it is the big one, if you only need one then it is small hole.

Daniel Defense has the upper if it is large hole.