View Full Version : Colt Sp1 threading

April 4, 2011, 09:34 PM
I asked this over in Rifle last week with 0 response. Perhaps you folks could answer my question?

My 1975 SP1 has a factory threaded barrel and flash hider.

If in the future I decided to pursue a suppressor for this rifle, does anyone know if the factory threading is the right pitch for most common 5.56 suppressors?

April 4, 2011, 09:41 PM
1/2-28. :)

April 5, 2011, 05:31 PM
Thank you.. not being at all familiar with suppressors, is that a pretty common thread pattern?

April 6, 2011, 10:31 AM
Exceedingly common. You'll have no issue with finding what you want. :)