I had this old Remington rolling block sporter restored a while back. The gunsmith who did the metal work and I had a long discussion about what to chamber it for. Since it was originally a .38 rimfire, and I wanted to keep it as close to original configuration as possible my first thought was .38 SPC. Then I figured why stop there? Why not .357 Magnum then? So after a discussion about pressures, renewing the heat treating, and barrel liners, we decided to put a liner in the barrel and chamber it for .357 Magnum. Since I got it back from the gunsmith I'd shot nothing but .357 Magnum in it, and I chronoed it at 1800 fps muzzle velocity. It's pretty close to .30-30 ballistics with .357 Mag cartridges. So far it's shown no sign of any undue stress, but I still feel like it's pushing things a bit. I shot some .38 SPC in it for the first time yesterday, and it was like heaven. With .38 SPC it's like shooting a .22 LR, and it's very accurate. I like it so much with .38 SPC that I'm finally thinking about marking the barrel with the new caliber. I was hesitating to do that because the old mark is simply "38" on the bottom of the barrel, and X-ing that out and adding ".357 Mag" just didn't appeal to me. For one thing, I'm not certain the rifle won't wear out prematurely shooting .357 Mag. For another, I understand that this rifle is experimental and that I need to keep a sharp watch on it for signs of stress. It's built and spec'd to handle 150% of .357 Mag pressures, but that's 300% of .38 SPC pressures. But would the next owner understand these things? So I'm leaning toward marking it with a new "SPC" underneath the old "38" marking, and just letting it's .357 Mag chambering be my secret. What do you guys think?