Well, if you don't like your gun, don't like your face, and don't like your life...then go right ahead and be foolish and overload them. Just make sure to tell the guys shooting next to you at the range that you're 3gr over max before you endanger their lives too.

Otherwise, I'd say DON'T DO IT! You very easily could be having pressure excursions on the order of 70,000-90,000psi or more. It's nothing short of a miracle that the rifle hasn't blow up already. In fact, if I were you I'd take that gun to a good gunsmith and have him thouroughly check it for damage before you shoot even normal loads in it again. You could very easily have microscopic stress fractures in the steel that could let go at any time, even under what would be normally safe operating pressures.

Is a few FPS really worth the risk? If you need the performance that the overloads provide, you need to think about another rifle with a more powerful cartridge like a .270 Wby. Mag., 7mmMag, etc...

Mike