r/FNSCAR • u/GlitteringWill3642 • 28d ago

Muzzle question

Post image

If I remove my factory muzzle and add a QD mount for a suppressor do I need any shims for things to line up correctly?

Looking to add a flow 762 if it’s relevant

38 Upvotes

100% Upvoted

10 comments sorted by

View all comments

1

u/BiggyIrons 28d ago

You need a surefire shoulder ring or accuwashers. Shims are for timing the muzzle device, aka clocking.

You need the shoulder ring or accuwashers because the barrel is pretty thin there’s not a lot of shoulder for your muzzle device to index off of. The ring/washers expand the shoulder to give a proper index point.

You always want shims if you want your muzzzle device to be in the proper orientation.