Necking 300 saum to 7mm
- Thread starter PorkChop
- Start date
I'll tell you if you have some extra brass.........
just kidding, yes it is possible to neck down to 7mm. It could be done in two steps if you have the neck bushing style dies. I don't think this is a requirement. I would also say that it will make the neck wall thickness increase. I can't predict how much of an increase though. I would guess that your chamber has some extra room for this. If you already have a load for the 7 it may be wise to start low on this brass and work your way back up. If you have neck turning tools this isn't a problem.
R
just kidding, yes it is possible to neck down to 7mm. It could be done in two steps if you have the neck bushing style dies. I don't think this is a requirement. I would also say that it will make the neck wall thickness increase. I can't predict how much of an increase though. I would guess that your chamber has some extra room for this. If you already have a load for the 7 it may be wise to start low on this brass and work your way back up. If you have neck turning tools this isn't a problem.
R
I just necked down 300 nosler brass to 7mm. Did it in one step with a standard RCBS full length die. Went really easy, not sure if there is a donut that would cause problems without turning, but Im not worried about it as none of my bullets will be seated past the shoulder junction being in a long action 188fb.
I use a Whidden dies set with neck bushing to go from 300 Norma to 7mm. I also bought a neck bushing to get the bullets to be tight enough to hold them.
I think Redding neck bushing die set in 300 Rsum would work also. The big thing would be to run them in the gun as to check the shoudler is right.
Then start slow fire form case then start reloading again
I think Redding neck bushing die set in 300 Rsum would work also. The big thing would be to run them in the gun as to check the shoudler is right.
Then start slow fire form case then start reloading again
I will say this, not sure if its to do with it starting as 300saum brass or not. I cut my chamber to GO +.001, and the VIRGIN Nosler 300 saum necked down brass grows about 0.006" at the shoulder after firing. This could be the same case with out of the box 7 saum brass, but I dont know for sure. With this being said, I will likely end up firing them all once before expecting any serious accuracy from them. Well see though, have a ladder test all set up, just need to get to my longer range to shoot them.
