I finally managed to get a Jarvis .357 sig barrel for my USP .40F. Alot of people, including jarvis barrels said that it wouldn't work and the only way to even get by was to only put 5 rounds in the mag.  Tonight I took the gun out to my local range and put 200 rounds of S&B .357 sig ammo through it without a hiccup!!  I did make sure and really rap on the back of the mag before inserting into the pistol to insure that rounds where seated in the mag firmly. It's like shooting off a mini A-bomb with these rounds!! Much sharper recoil than my Delta Elite 10mm.

idaho-ar15