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Bumping shoulder on co-ax with body die?

V

Vandy321

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Have a forster Co-Ax, and use redding comp bushing dies

Is there a way to bump the shoulder accurately with the body die? Cannot use the redding comp shell holders on the Co-Ax.
 
Thanks.

Right now, with it set to a healthy cam over, the shoulder actually grew .001

Assuming that brass isnt compeltely fire formed.

With that die on the regular s-plate, will just touching, but no cam over set the shoulder to saami? And I can cam over as needed until it bumps

Right now I think I'm still .007 under saami and the cam over isnt bumping shoulder
 
What do you mean touching? You turned it in with the handle down until it touched? I bet if you screw it in a bit deeper than first tangential contact you will make that shoulder move.
 
Novice reloader...just trying to make sure I'm doing this right.

Stripped the bolt. Brass chambers fine still (it did before I body sized it too, but wanted it all uniform for load development, as it was fireformed at slightly different pressures during seating depth test)

Assuming another firing or two and it wont chamber? I'll probably have the adapter for the shellholder by then, and assuming I do, should make bumping the shoulder back a specific amount easier.
 
No it won’t make it any easier. It will just drain your wallet 50 bucks. Try giving some more details and turning the die in further.

What’s a healthy cam over? You set it to touch and that it? Quarter turn past? Any more turned in and the press won’t hit the bump stops? Providing actual details is the only way we can know anything.
 
What do you mean touching? You turned it in with the handle down until it touched? I bet if you screw it in a bit deeper than first tangential contact you will make that shoulder move.

With the press down, I screwed the die in until contact, then backed it off a 1/16 turn, no bump. Kept screwing it down until touching, still no bump. Set it for a bit of a cam over, still no bump. I'd say the press cams over about 1/4" before it reaches the stops

Not sure if I just cant read my RCBS Precision Mic correctly, but i started at .037 on the gauge (below zero). Fireformed it went out to .043 (still below zero on the gauge). Which is growth of .006. After the cam over set, still no change in the mic reading (.043)

Rifle is a 300wm, brass was virgin and fired formed at a low initial pressure (73gr) while seating depth testing
 
It’s probably not fully grown as you said. Belteds usually have a good bit of growth to go from virgin.

But don’t worry about cam over etc, you can probably screw that die in far enough to move the shoulders since you’re still hitting the stops. It’s when it’s no longer hitting the stops and you’re no longer getting a full consistent stroke to the mechanics stop that you have an issue. I wouldn’t turn it in more... the brass chambers and that’s more than enough.

Now the issue could be that the die is bottoming out on the cases belt or something but usually the situation is the opposite in that the die doesn’t reach all the way to the belt so it’s doubtful but I suppose worth a check.
 
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I contacted Forster regarding this and was told I could bump shoulders using their Coax press. Using same procedure one uses with any other press. Set die til it touches, then a bit more ( a bit more is experiment til you get the bump you want). I'm using an RCBS FL sizer die and bumping a consistant 0.002" FWIW, lg
 
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Given that it headspaces off the belt, and the shoulder spacing isn't critical - I think you have much further to grow in your chamber before you need to worry about bumping it back.

How far does factory ammo blow the shoulder forward in your rifle?
 
Given that it headspaces off the belt, and the shoulder spacing isn't critical - I think you have much further to grow in your chamber before you need to worry about bumping it back.

How far does factory ammo blow the shoulder forward in your rifle?

Never fired factory through it, first rounds down it were my best hack at brass prep/reloading
 
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I'm running a Forster Co-Ax, and routinely bump the shoulder when wildcating etc. Easiest way I found is with a Whidden Gun Works Case Gauge. I can measure the shoulder quickly and repeatedly. I just adjust my FL die accordingly.
IMG_20190804_175727.jpg
 
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Thanks fellas, that's my plan, I returned those redding shellholders, going to use the redding body die and the RCBS precision mic case gauge to measure.
 
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I have several 300 WM and been loading for many years. First of all new 300 WM will be all over the place since it was designed to headspace off the belt. For one of my rifles the new Norma brass is .017 shorter than the chamber. Fire form the brass and and then set the die to set the shoulder back .001-.003 just like you would with a non belted cartridge. Oversizing the brass will shorten case life and possibly lead to case failure. I use Redding Type S die and the bottom of the die doe not contact the shell holder. To size the case in the area of the belt get a Larry willis collet die.