Controlling Shoulder Bump with a CO-AX

[ranger3]

I do shoulder bumping for both my 243 + 260 on my Forster coax press I have found that it takes just a couple of times. What I do is cycle the brass in the action that I'm using it in and resize just slightly until the brass fits and cycles easily. I take a headspace measurement and lock up the ring on the die and it is consistent every time. There is a key in holding the handle on the downstroke for a few seconds to make sure that it sets up. Annealing is essential and I have found an oil lube works best. I have also found the Forster shoulder bump die works very well for this.

 

[fatelvis]

Universal Click Adjustable Lock Ring - Whidden Gunworks

The Universal Click Adjustable Lock Ring fits both standard and co-ax presses. Please Note: The Universal Click Adjustable Lock Ring is not compatible with the Dillon Floating Toolhead.

www.whiddengunworks.com

Whidden’s adjustable lock rings work beautifully for setting up your die for correct bump.

 

[6BRA]

Universal Click Adjustable Lock Ring - Whidden Gunworks

The Universal Click Adjustable Lock Ring fits both standard and co-ax presses. Please Note: The Universal Click Adjustable Lock Ring is not compatible with the Dillon Floating Toolhead.

www.whiddengunworks.com

Whidden’s adjustable lock rings work beautifully for setting up your die for correct bump.

^^^^ 100 percent! ^^^

 

[marchboom]

This is not a problem. Just get a micro-adjustable seating die and make the appropriate adjustments for the different rifles. Shims don't work and you lose the benefit of the Co-Ax shell holder if you use a standard shell holder.

 

[fatelvis]

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...???

I have ignored the "Ol standard" way of measuring from the top of the belt to the datum on the shoulder on the 7mag, 270 Weatherby Mag, and 300Win mag. I measure from cartridge head to datum, just like I do when I size the non-belted cartridges. I never had a lot of luck using the belt as a reference point.

 

[fatelvis]

This is not a problem. Just get a micro-adjustable seating die and make the appropriate adjustments for the different rifles. Shims don't work and you lose the benefit of the Co-Ax shell holder if you use a standard shell holder.

Micro adj seating dies are good for precise OAL experimentation, but they have no part in bumping the shoulder back a set amount.

 

[marchboom]

I just use separate sizing dies for each firearm. Much easier than constantly adjusting one die. And these FL sizing dies are not that expensive. My time is worth more.

 

[whatsupdoc]

I setup my die for a certain bump then paint a mark on the die that lines up
with the cut on the adjustment ring. If I need a little more or less is easy with
reference marks.

 

[Webster]

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...???

Erik Cortina on one of his videos shows how he adjust dies for bump. With a digital caliper he measures from the bottom of the lock ring to the bottom of the die. Turn the ring until you get the amount you need to go up or down.