Shoulder bump with different brass?

[muleman69]

Sizing some brass last night and getting two different readings ? Set die up to bump my .300 win brass .002-.0025. Ran a batch of Nosler through and all went well, then I ran some Norma and my shoulders bumped back .005-.006 shorter? Should I have reset the die for each manufacturer?

 

[jepp2]

Need to know the before sizing dimensions to understand your shoulder setback.

Brass can be different compositions from different manufacturers, and the hardness due to number of firings/sizing cycles can affect sizing results.

 

[JFrank]

Are these FF prior to sizing?

 

[Uncle Ed]

Get some Redding competition shell holders, they let you adjust the amount of shoulder bump by just changing shell holders.

 

[JFrank]

^^^ perhaps some color glossy pictures or videos are in order.

 

[muleman69]

This is probably the fourth reloading on the Nosler and second on Norma. I will get more info when I get back to shop. Sorry but I'm not savvy enough to send pics. I would like to figure out how one day though

 

[JFrank]

Nosler brass I've used has always been on the softer side, never tried Norma.

 

[bugman]

Two things to consider and check out:

1. Did you confirm after the second firing that the Norma was fully fireformed by amount of bolt fall on a fired case? If not, you may have not bumped the Norma at all, and your ''short headspace" was not due to the die.

2. The brass itself. The harder the brass (from the number of firings or the brass composition or the annealing) the further that die has to be screwed down to achieve "x" amount of bump. IOW, softer brass needs less die adjustment than harder brass

 

[JFrank]

Sizing some brass last night and getting two different readings ? Set die up to bump my .300 win brass .002-.0025. Ran a batch of Nosler through and all went well, then I ran some Norma and my shoulders bumped back .005-.006 shorter? Should I have reset the die for each manufacturer?

Probably

 

[Uncle Ed]

^^^ perhaps some color glossy pictures or videos are in order.

No problem, hitting a turkey is right up my alley

 

[JFrank]

Excellent!!!

 

[muleman69]

Two things to consider and check out:

1. Did you confirm after the second firing that the Norma was fully fireformed by amount of bolt fall on a fired case? If not, you may have not bumped the Norma at all, and your ''short headspace" was not due to the die.

2. The brass itself. The harder the brass (from the number of firings or the brass composition or the annealing) the further that die has to be screwed down to achieve "x" amount of bump. IOW, softer brass needs less die adjustment than harder brass

Thank you

 

[ppaul]

Another thought is there are some close measurements in regards to the case head and the shell holder. I just measured both and all are closer than I would like for working with different brands of brass.

shell holder;
deck height .123
diameter of chamfer on shell holder top face .530 ( it's early and just used old eyes and caliper)

case head;
face to bottom of belt .125
belt .532

 

[243winxb]

Shoulder Bump-

Does lube on the case shoulder make a difference? (Spray lube)

Compared too.


Pad lubed, no lube on shoulder? (RCBS pad)

I'm not buying any spray lube to test this. Has anyone?

 

[Uncle Ed]

Hornady One Shot that dries and is very thin does not migrate to the shoulder like other lubes and effect shoulder bump.

Home made alcohol and lanolin and Hornady Unique can be squeezed upward to the shoulder area and effect shoulder bump.

Even wiping the shoulder and neck area any excess lube on the case body can be squeezed upward into the shoulder area.

Cases with a sharp body taper like a 30-30 are effected more than cases with less body taper.

 

[fatelvis]

Get some Redding competition shell holders, they let you adjust the amount of shoulder bump by just changing shell holders.

I agree with Uncle Ed. Also annealing all of them might be a good idea. Annealing them should make them all close to the same hardness and help control spring back. The different brands/lots also may have differing wall thickness, which of course, you can’t do much about. Good luck!

 

[Zero333]

Some brass conforms easier than some other brand of brass...

This is also the case with the same brass that's been annealed and that hasn't. The brass that was annealed will conform easier and spring back less.

 

[muleman69]

Get some Redding competition shell holders, they let you adjust the amount of shoulder bump by just changing shell holders.

I do have some for the -06 family and will be ordering some for the .300. I use a Redding F/L die with ball removed and imperial wax. Just from reading these post I can see Im screwing up as I have waxed body shoulder and neck. I will be changing my practice now for sure thanks to all the great post's

 

[JFrank]

I have some of my biggest challenges measuring brass with comparators while setting headspace, on occasion I'll hold my press handle down for a three count on stubborn brass. I also use a feeler gauge under the shell holder to set the Die height. I recently adjusted from.011 to .010 again using a three count they don't spring and chamber freely.
I do use a lube on the cases prior to sizing

 

[Dusty Stevens]

Usually the culprit behind different bump lengths is lube on the shoulders. You really only need a little bit of sizing wax on the bottom half of the case. If you start seeing it on the shoulder area when pulling the case from the die youre using too much. I have an old bent pistol rod with a 12ga cleaning mop on it- when i see the lube creeping up on the case ill mist that mop with carb cleaner and run it in the die to clean it up. Any lube besides imperial will at best cause bumping inconsistency and at worst a stuck case.