I hope you folks don't mind me borrowing
I am very new to the AR seen. I have a
Colt SP1 lower ser# SP84xxx which
I believe places it from the '78-'79
It looks like the receiver is the type
with the larger front pivot pin. Does
anyone know a good source to get an offset
pin that will allow me to use uppers that need it?
I have also read about some receivers made
with a sear block. Of course i'm just trying
to better understand what I have ( nothing
illegal). What exactly does this block look like ? and where would it be ?
Any other insight into what I have here would