CMMG Piston Conversion question...

[Egreen6823]

This might be a dumb question but I am curious how you ensure the gas port on the barrel mates up to the port on the gas block? It has a pinned a2 sight so there is no way to mess up the alignment and since I dont have a gas block to look at I am curious how you make this work without screwing it up
thanks in advance guys

[Egreen6823]

bueller?? bueller???

[m16]

Plug the chamber end, put your mouth on the muzzle and blow through it while rotating the gas block.

On every low-profile gas block I have ever seen, the hole is much larger than the gas port in the barrel.

Not sure if this applies to piston systems.