I have a Mauser Vergueiro in 8x57, at the moment I'm using Winchester factory loads in it. Now although bolt lift and extraction are easy, the cases are comming out with flatened primers. Are WIN primers soft or should I be worried about pressure levels?

Bakes

Have you had your headspace checked? If your rifle's headspace is a little sloppy, you could see this effect. This is as the firing pin slams the case forward, up to the shoulder, before igniting the primer. The primer itself backs out of the case on ignition, to rest against the bolt face, and be flattened as the case fireforms to the chamber dimensions. To my mind, a good 'test' would be to partial-size and load one of the fired cases (don't bump the shoulder back) and, if that firing produces a nice rounded primer, you can be sure that the problem was headspace to begin with. Not a very big deal if you reload - just stick with partial-resizing (or neck-sizing), and your headspace problem will be a thing of the past, provided you don't push the shoulder back in your sizing die. Sneaky advantage here is that you could gain a tad of powder capacity for free. The other alternative is to have your headspace professionally checked and the barrel set back.

Hope this helps

Rikkie

Rikkie is right on target. Flattened primers from mild factory loads like 8 x 57 are the result of the chamber being somewhat longer than the cases. This is extremely common with the 8 x 57 (as well as many other cartridges). Your headspace situation is not dangerous, but if reloading for your rifle, do as Rikkie suggests and do not push the shoulder back in the resizing process any more than necessary to easily rechamber the reloaded cartridge. If full length resized and fired a couple of times, you may suffer a split or separation of the case at the pressure ring about a quarter-inch in front of the rim.

Thanks guys, I don't reload for this gun yet when I do get around to it I'll get a neck sizer as well and go from there.

Bakes