How Strong is a Remington Rolling Block?

[coop923]

I posted a while back about a Remington Rolling Block in 7x57 that I have, and safe loadings for it. Someone mentioned that there were excessive headspace issues with many of them. I remembered something about the fired brass, but I couldn't remember details. I came across some of the brass and thought this might be part of the headspace issue:

The shape of the chamber seems to be larger where the neck meets the shoulder, causing the brass to expand when fired. Fired brass will not chamber in the 7x57 Model 95 Mauser I have.

Am I on the right track in identifying the headspace problem?

The action is tight and the gun is in good shape; it seems I could remedy this problem if I re-chambered to .280 Remington/7mm Express. Am I right? Is the action strong enough for the increase in pressure from 7x57(SAAMI 46k vs 50K)? Or is the 100 year old metallergy not even strong enough to shoot modern 7x57 loads? I loaded starting loads for it many years ago and nothing more. I would think these would be safe. Any thoughts?

Edit: I'm thinking about shooting cast bullet loads at 1000-1600fps or so... not stopping big game -just fun stuff!

 

[Jim Watson]

I don't know if expansion at the junction of neck and shoulder is a sign of excess headspace but there is little doubt that it does have excess chamber headspace.
Not all Rolling Blocks could be that worn, it seems likely that somebody changed the specifications while we weren't looking. Or that Remington got something wrong, considering that the 7mm came out in 1893 and they didn't build Rolling Blocks until 1901-1902 time frame.

I would just fireform 7x57 and either neck size or partially size so as to not set the shoulder back and risk casehead separation, which is a very bad thing in a Rolling Block. The action is just a box and when it gets full of hot gas, pieces go everywhere.

Starting loads or cast bullet loads seem about right. I had an old article by a guy who shot cast 7mms in neck sized brass for many loadings.