Controlling Shoulder Bump with a CO-AX

[Full Curl]

I'm trying to shoulder bump 7mm rem mag cases back .0015 to .002 using a CO-AX press and FL Forster die. Is there a better way to find the perfect die setting for the .0015 to .002 bump rather than messing around with a ton of trial and error screwing the die in and out? I'm tired of going little by little in with the die only to find that I then over bump the should and have to fire form the case again and start over. I'm reloading for more than one rifle here with 1 die so I really can't just set it and forget it since it changes between rifles.

I love the idea of Redding's comp shell holders for controlling that last few thousands for the perfect bump, but they won't work with the S jaws on my press. There must be a more accurate, more effective, and more efficient way to do this than I'm using...???

 

[J E Custom]

I'm trying to shoulder bump 7mm rem mag cases back .0015 to .002 using a CO-AX press and FL Forster die. Is there a better way to find the perfect die setting for the .0015 to .002 bump rather than messing around with a ton of trial and error screwing the die in and out? I'm tired of going little by little in with the die only to find that I then over bump the should and have to fire form the case again and start over. I'm reloading for more than one rifle here with 1 die so I really can't just set it and forget it since it changes between rifles.

I love the idea of Redding's comp shell holders for controlling that last few thousands for the perfect bump, but they won't work with the S jaws on my press. There must be a more accurate, more effective, and more efficient way to do this than I'm using...???

The simple way to bump the shoulder on any case is to leave the die in its original setting for your loading, and simply take a feeler gauge, starting with a .001 gauge and place it between the shell holder and the case head while you size one. if that is enough, place it under the case head every time you size, or cut a small .001 shim and leave it in the press until you are done.

That way you don't have to buy special shell holders of two or three different sizes for every cartridge you load.

Also some cases may have more spring back and require a little more bump so all you have to do is add .0005 to the shim thickness. I separate all of my brass by brand and number of firings eliminating this problem.

Simple, but works very good.

J E CUSTOM

 

[orch]

Hey there,

Pretty sure Forster does make an adapter for standard shell holders that you can replace the s-jaws with, then you could use the Redding comp shell holders in it... But by the time u buy the adaptor and set of shell holders you could probably just buy a second RCBS sizer die and set it up for each gun and be even $.... Would take less time than changing out the jaws too....

Suppose you could also set the die for one rifle and index your die and mark it some how then set it for the other and index and mark it...

Love my co-ax but I still have my rock chucker set up next to it on my bench for situations like this.... The coax is awesome for "set it, forget it" situations, switching between dies is quick, but once you want to start experimenting with minor changes in depth it can take a while to fine tune each time...

If I were you I'd just buy a second sizer die for the other rifle and set it and label it for that rifle....I had two 25-06ai's that were 0.005" different in headspace (cut with the same reamer) that I tried going back and forth with the same fl die on the coax and it was a major PITA...Finally went back to rock chucker and set it for the shortest case and used my Redding comp shell holders to find the correct headspace for the one with the longer headspace.

Good luck

Orch

 

[Mikecr]

This is another advantage in using Redding body dies for separate bumping. They're cheap, can be customized, and I have one set for each chamber.
Keep it in a box for each chamber, along with all else needed to reload for that chamber.

I hand screw it in the press & go to bumping.
For tiny tweaks, there are 3: shellholders, shims, lube
I happen to prefer lube with re-bumps till exact desired HS is reached. In other words, I run with a slightly under-bump die setting, so that I can dial in final with a re-bump.
But you can set it up so that any of the 3 adjustments will work as easy.

That said, I don't use FL dies, ever, so my system may not apply directly for your situation.