A large diet of heavy loads can cause any stock to fail long term. From a safety stand point I think that we all mostly agree a Sterlingworth and NID are very much capable of handling a load in the 9,500-10,000 psi. The action is strong and the barrels are robust. It is the wood that might be in question and unless you are looking to shoot huge numbers of heavy shells it should stand up to moderate use. And if the stock cracks there are thousands of Sterlingworths and NIDs to take their place. We are talking about a basic, heavy duty, American field grade gun not a light weight British gun meant to shoot one ounce loads. So enjoy it and put it to work.