280 AI resizing

[rharfo]

I know this has been asked numerous times but I'm just too irritated to search.
Long time reloader of 280 AI Rem Improved 40. Rifle is pre saami just like the dies. All of a sudden the shoulder will not set back and is growing. I can neck size but want to set back 1-2 thousands and try my sample pack of Hammer bullets. I have a few pieces of resized brass that won't chamber! Just when I think I know what I'm doing I get punched in the face.

 

[lancetkenyon]

Can you adjust your die down any further?

If it is already hitting the shell holder, just take a dremel or belt sander and take a couple thousandths off the top of the shell holder or buy a new "comp shell holder" that is slightly thinner.

 

[rharfo]

Comp she'll holders are +. I need minus

 

[nksmfamjp]

Annealing is likely your solution. More cam over can work.

 

[QuietTexan]

Anneal, stone the top of the shell holder or the bottom of the die, or buy a new die are the three solutions I would go with. So basically what they ^^^ said.

Growing shoulder is likely a brass hardness issue and the case is springing back at the shoulder but the body part of the die is still working down along the body.

 

[rharfo]

Ok, thanks I am shopping annealers....

 

[QuietTexan]

If you have a hand torch already you can stick a case in a socket and spin it with a drill to see if it helps, before committing to buying anything fancy.

 

[VinceMule]

Take .003 off the top of your shell holder. I gently touch the side of my bench grinding wheel, and dip in water often. Use your calipers to measure from top to bottom.

Your brass may be very work-hardened. I anneal with a propane torch and pan of water, been using this technique for 30 years, and it works. I do not heat up the shoulder as annealing the neck is enough heat on the shoulder.

OP, your problem is simple, and it is typical for a custom rifle with a good match chamber with a minimum spec chamber. The fix is simple and cheap,

Good luck

 

[MagMan]

Have you tried sizing without the expander button? You might be pulling the shoulder forward if that button comes out tough especially if you don't lube the inside if the neck.

 

[rharfo]

Have you tried sizing without the expander button? You might be pulling the shoulder forward if that button comes out tough especially if you don't lube the inside if the neck.

I'm using spray lube and have not tried removing the expended button but will give it a try. Thanks

 

[nwmnbowhunter]

How much is the shoulder growing? That will tell you how much you need to remove from shell holder/ or bottom of die.

 

[rharfo]

How much is the shoulder growing? That will tell you how much you need to remove from shell holder/ or bottom of die.

I will have to check again but it was several thousandth's

 

[RUFFIAN R - NY]

Try a different shell holder all are not created the same.

 

[epoletna]

I was having difficulty setting shoulders back on one of my cartridges, so I took a shell holder and ground the top of it very slightly. We're not talking much here, and you don't want to weaken the shell holder.

You might need to anneal the brass before setting. the shoulder back.