What is the maximum safe PSI inside the chamber of an automag lvl 7 valve ?

[knownothingmags]

What is the best material to devolumize a mag to use 12 grams on a classic valve?

nylon, delrin, there are a lot.
talk to the guys who have done it.

[Spider-TW]

nylon, delrin, there are a lot.
talk to the guys who have done it.

I used flyingpootang's method of a number of 3/8" nylon washers. They have to be reduced on the OD a bit, but you can add and subtract volume in an easily accountable method. Too many washers gets the chamber pressure up where you start to see more broken paint and/or venting from the reg piston. Barrel length is just as important as the last few washers. My son went to a stubby minimag barrel on his devolumized pumpmag, and it started seeing both problems on occasion (small tournament paint probably).

here's a drag-up

http://www.automags.org/forums/showthread.php?249391-30-Shots-from-a-classic-valve-w-a-12G&highlight=shots