Contender fatigue

[SL11]

I am wondering what the effects of too-hot loads are on the original style Contender. I have one in 30 Herrett, and am still trying to figure out how to build loads that are at the top of, but not beyond the gun's comfort zone. (Not my comfort zone, the gun's.) The cartridge seems to have been designed to shoot a case full of IMR-4198 at about 48,000 cup, but loads in manuals don't seem to go there anymore. Manuals have loads that are all over the place, with cautions about large variations in free-bore in different barrels causing wide variations in acceptable loads. Accurate Powder's loading manual says that Thompson Center told them to keep Contender loads below 42,000 psi, but TC claims to have no memory of telling them that. And, the original Contenders have been barrelled in higher-pressure cartridges with the same case head size, like the .375 Winchester and the 6.5 JDJ. So, I am trying to figure out how to load the thing for long gun life as well as substantial power.

In another thread on this board,
dgr416 wrote "I have an old contender a 195000 range. It tore up quickly with the 375 jdj I shot about 50 times. I hated that it tore up that sucked.I have to send it to TC now."

I'm wondering what he meant by "torn-up." What are the signs in brass or gun metal that I should be looking for to tell me that my gun is not comfortable with my loads?

SL11