I have to agree with Big Ken. Mine is the hardest kicker in the stable, and that includes my 45-70 guide gun and my Win.Model 70 Featherweight in .358. But if I do my part, I've had 1/2 inch groups off the bench with the Remington 250 grain factory loads.
ya i have the 7600 whelen carbine and it belts pretty good with 200's. it just about ejects the shell itself off the bags. i will be trying the 250's this weekend after getting my trigger done and new scope mounted. it still doesn't hold a candle recoil-wise to my win 94 timber carbine in 450. that thing really belts you.
I have the same issue with mine! Most times, the action opens during recoil. If I shoot it standing up with no hand on the pump handle, it will actually auto-eject! I had it to a Remington certified smith who told me if he roughed up walls the chamber a bit it might hold the expanding cartridge case better - didn't change a thing!
I'm loath to mess with it cause it shoots so good, but that is a bit un-nerving!