New to 57 reloading

[mrcobrajet]

I finally got around to trying to reload my 57 rounds for my FsN. I tried RCBS resizing dies and like the other on the forum the die stripped the coating off no matter what lube I used. Bought a Lee sizing die and with RCBS sizing lube I can resize the brass without stripping the coating and the fit perfect into my EA gauge. I searched the forum for load data for 40 grain vmax and decided to use HS6 powder with CCI400 small rifle primers.

my first batch was loaded with 6 grains and they chrongraphed around 1875 fps but the primers where definitely flattened. i did lose a couple of primers also but they all came from brass that was crimped. I didn't like what i was seeing and was confused as I have seem data that folks where loading with HS6 up to 6.8 grains so I thought i was going conservative. I decided to ladder up from 5.4 grains up to 5.8 grains.

The rounds loaded at 5.4 grains most closely matched factory SS197 FN rounds measuring on the chrono arounf 1675 to 1715 fps. This load has no over pressure signs, no lost primers, and the firearm cycled well.

my question to the forum is it unusual for 57 pistols to vary on how they tolerate loads levels? I am no where near the levels that other members are loading at and that doesn't bother me as I just want a good safe target load that I can load up. I also plan to purchase a PS90 in the near future and want a load that will work in both platforms.

Any advice would be greatly appreciated.

[panzermk2]

5.7 is hell on primers. Flattened primers are normal, it does not mean over pressure like it often does with normal calibers.

You want to make sure not to over swage your primer pockets. In fact if it has crimped or not just kiss the rim, yes LOL, of the primer pocket. Do NOT fully swage and do NOT get carried away with cleaning the pocket.

Also use small rilfe primers not pistol .

[Localizer]

6.4-6.6 is likely top end for 40gr vmax.

What’s your OAL? Should be closer to 1.62”