Yes - cock on opening - so, Model 30 Remington, A. Yes- bottom metal has been flattened - they are all kinked originally.
You can make just about any ctg. in it, including a .375H&H.

I had one that was 150fps slow at max pressure as an '06. Since it had a new-ish barrel, I re-chambered it to .300 Win Mag. thinking I might get H&H ballistics, but as a .300 Win mag, it was 200fps faster than any book at max pressure. Nice to get 3,300fps with 165gr. Noslers.
Funny, as an '06, it was most accurte with 180's and 220's, but as a .300 Mag that barrel loved 165's, didn't like 180's and hated 220's.
With 165's, it would hold just under an inch most of the time for 5 shots, with the odd 5 shot group hitting 5/8". Wonderful goat and sheep rifle for stretched ranges.