I always set my barrel down tight on the go gauge but i am begining to wonder about that. What i have read is that the no go is really set up at the maximum saami spec and the field gauge is the one that is too long.

So it seems to me you could make you chamber a little (very little) longer without having a problem. We all know factory brass shoulders are much shorter than SAAMI spec and as reloaders.we are measuring our shoulders on fired brass and set our dies up for a .001 shoulder bump anyway. So after fireforming chamber length really doesn't matter within reason.