147 gr bullet was used long ago on the P9 when power factor
was at 175 minimum. The P9 was known to crack the slide but it held
up with a heavier bullet, so shooters started to shoot 147g bullet so that
its not so hard on the gun.
I have heard thru the grape vine that glocks dont hold up in open? PF is high
and slide will eventually crack. So shooting 147g bullet will be the ticket!
It is true that the more powder to use, more efficient the comp will work. I would
try the slowest burning powders like Autocomp,Hs6,IMR7625, Vihtavouri N105, N350,3n37,3n38, Ramshot silhoutte and see how that works out. Hope this helps.