Remington Rolling Block 7x57
 

I recently acquired a 1901 Remington Rolling Block 7 mm. This is supposed to be the 7x57, BUT maybe not exactly. This model was built for several nations armies, and this rifle has a bayonet lug. I have read that this model MAY have excessive headspace and require modified brass for loading safely and shooting. Other sources say they fire standard sized 7x57 ammo. I took the gun to a local gunsmith who superficially looked it over, said it looked very good and safe to fire, but did not specifically measure headspace even though that was my specific question. I do know that this gun should be loaded with cast bullets and at much lower pressure (velocity) than modern 7x57 weapons. I have read about methods of neck sizing with a .30 caliber die, then partially neck sizing only with the 7x57 die to create a false shoulder, loading the ammo and firing to produce fire-formed brass to then be loaded for this gun. This process is described as being hard on case necks, requiring frequent annealing of the necks. One source also indicated that this neck sizing requires a neck sizing die while others imply that it can be done with a regular die so long as you do not size the entire case. This whole process seems like more than I may want to tackle, but I hate to give up without trying. I already have 7x57 reloading dies and brass as I have loaded (much hotter) ammo for a Ruger #1 in this caliber for years. I may not ever shoot this gun a lot, but would really like to shoot enough to determine point of aim and to kill a deer with it. The rear sight is a ramp for elevation which also can be raised for greater distances. There are numbers on the left side of the ramp from 1 through 5, and on the elevated portion from 6 through 19. I wondered if this represented ranges from 100 to 1900 yards? Any reliable help with info about safely shooting this gun would be appreciated.

According to what I've read, A 7mm rolling block action in good shape should be able to handle up to 40,000 psi pressure. Keep your handloads well under that and you should be OK. I've also read that the chamber dimensions of some early 7mm's may vary from current 7x57 dimensions, causing potential problems, including headspace. There are rolling block forums out there that can provide more detailed information. There is no reason not to shoot it, if it's in good shape.

your on the right track, take 1 case, punch it out to 30 cal with an expander ball, the neck size till the action closes with a bit of resistance, then screw your die down 1/16th turn. resize again and measure that case compared to a factory 7mm cartridge, if they are the same you just load as normal within the pressures you need to use. if they are different you may have to make all your cases for it, not a big deal once you know what size to make them.
RR
edited to add, or you could order go/no go gauges for a 7x57

The Rolling Block 7x57mm rifles usually have long headspace. You really do not want a case head separation in a Rolling Block Rifle. There is no gas relief built into the action, you get all the gas and brass right in the kisser.