SIGP240 wrote:Gen 2 G20 owner here. Grips are clubby. Factory recoil spring had to beefed up to digest 175 HLTC WITH 10.0 grains 800-X. Mimics rather high energy muzzle blast with two illuminated fire rings 8 and 16" out. Gas velocity must be supersonic. Recoil not for the limp wristed. 6% of the Underwood brass I pick up is nearly ruined by high pressure. It does size back on the Lee Bulge Buster, tho.
That's the thing about Underwood: Small company loading stuff hotter that the original Norma factory load, and some calibers that are pretty sketchy around the edges. I wouldn't touch their stuff with a 10 foot pole, and I reload 10mm all the way up to the Norma spec. If 6% of the brass is damaged by high pressure from factory loads so that it can't be used, that's a
BIG, BIG warning sign. Only question is when will your gun let go or prematurely come out of battery with the pressure still up, and how bad a case of brass acne you will wind up with.