ShootistPRS
New member
I have a year old 257 Roberts in a Browning A-bolt. I was able to get some used brass to reload (I'm very picky because I don't want the +P brass).
The problem I am having is that after cleaning, prepping and sizing the brass it won't chamber without excessive force. The problem appears to be that the cases were fired in a chamber that was larger diameter and my full length die is not returning it to a small enough size. I have the die set so the ram over-centers on it (which I rarely do) but it takes a lot of pressure to get the bolt to close.
I checked the case fit with dye at the pressure ring and at the shoulder case junctions and there is a bit of interference at both places with more on the pressure ring (just above the solid portion of the base of the cartridge) I am wondering if firing these tight fitting cartridges in my gun will make them a better fit over time.
What are the opinions here?
I should add that the reason I don't want the +P brass is that it holds about 10% less powder due to the heavier case. Since there are many 55000 psi cartridges that use the standard 7x57 brass as a base and most of my load data is for the standard cases It just seems like an accident waiting to happen. I have culled out all of the +P brass as it has shown signs of being used with the standard powder loads with tool marks in the head and loose primer pockets. I am going to stick with the standard brass as long as I can get it or the 7x57 brass and form my own 257 with it.
The problem I am having is that after cleaning, prepping and sizing the brass it won't chamber without excessive force. The problem appears to be that the cases were fired in a chamber that was larger diameter and my full length die is not returning it to a small enough size. I have the die set so the ram over-centers on it (which I rarely do) but it takes a lot of pressure to get the bolt to close.
I checked the case fit with dye at the pressure ring and at the shoulder case junctions and there is a bit of interference at both places with more on the pressure ring (just above the solid portion of the base of the cartridge) I am wondering if firing these tight fitting cartridges in my gun will make them a better fit over time.
What are the opinions here?
I should add that the reason I don't want the +P brass is that it holds about 10% less powder due to the heavier case. Since there are many 55000 psi cartridges that use the standard 7x57 brass as a base and most of my load data is for the standard cases It just seems like an accident waiting to happen. I have culled out all of the +P brass as it has shown signs of being used with the standard powder loads with tool marks in the head and loose primer pockets. I am going to stick with the standard brass as long as I can get it or the 7x57 brass and form my own 257 with it.
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