Quick question for the AR experts,

 

I want to take advantage of the sale at Primary Arms on the Geissele triggers.

 

I'm building a lower for my White Oak service rifle upper to shoot service rifle matches. 

 

My question is what is the deal with the small pin and the large pin? Witch one do I need?

 

Thanks in advance.

 

 

Large pin is for a relatively small number of old Colt lowers that were made with large FCG pins. Unless you have one of these lowers, you'll want a small pin model.

Thanks bud, you have a pm incoming.

Thats the ones with the screw type front pins ? Correct ?

Hey any colt fans out there. I have an odd one. This is why i acquired it. I have a hbar 11 carbine with colt defense stamp and regular front pin. Explain me that. Sorry to go off topic. Got it from a guy in az off g broker.