Grooved piston in your M1A?

[Fatelvis]

Does anyone use a grooved Sadlak piston in their M1A when shooting heavier loads? If so, do you like it? Thanks-

 

[30Cal]

They don't work well with ball ammo.

 

[madcratebuilder]

I agree. Use a GI piston for 150gr surplus ball ammo. The grooved piston does work very well with 168gr match loads. It's possibly the easiest part on the rifle to change out.