Guys shoot SAAMI loads in these guns all the time and they don't suffer catastrophic failure. However, they just aren't designed for it and more likely than not the SAAMI loading increases wear and the risk of stock damage if they are used a lot.
The marginal cost of using B-P or similar shells compared to the Wal-Mart variety isn't great enough to make me risk it and I switched to B-Ps and RSTs a long time ago for this reason. I would occasionally use the cheaper shells and fortunately did no visible damage but I just gave up on them - t'aint worth it!
My opinion only.
