Inconsistent shoulder bump? What am I doing wrong?

[christian1]

Working with twice fired ADG 300 WM brass. Full length sized with Hornady FL die. Checked a couple to make sure my should bump was right and starting seeing all sorts of weirdness. Measuring my shoulders I am not seeing a consistent .002" bump. Some have more and it varies all the way up to .005" inches more to .008" more. I haven't ever had this. What the heck did I do wrong?

 

[wapitibob]

Did you set up your press with comp shell holders so you could set the bump correctly and still have die/press cam over?

 

[christian1]

Did you set up your press with comp shell holders so you could set the bump correctly and still have die/press cam over?

yes

 

[packer58]

Variations in spring back due to work hardening the brass may be part of it .... As long as you have solid cam over and your die isn't moving it should be straight forward .......

 

[wapitibob]

yes

I got nothin
I don't even measure mine anymore
I do AMP anneal every firing though

 

[A382DWDZQ]

How do you lube your brass?
How do you measure your shoulder?
Annealed or not?
Die is clean?
Bolts in press linkages all tight?
Are cases measuring a consistent size before sizing?
Using expander ball or not? If yes, lubing inside neck or not?

 

[VA2MT]

Had this problem before. Took apart my Redding dies and thoroughly cleaned. Switched to Hornady One Shot case lube and haven’t had it happen again. I was previously using a RCBS pad and lube.

 

[christian1]

Had this problem before. Took apart my Redding dies and thoroughly cleaned. Switched to Hornady One Shot case lube and haven’t had it happen again. I was previously using a RCBS pad and lube.

Worth looking into that. Seems plausable.

chris

 

[yak]

May want to look at annealing since the brass is twice fired and you didn’t encounter this last time. Just an idea.

 

[christian1]

Using advice here I seem to have things back on track. Thanks guys.

chris

 

[35WhelenAI]

Using advice here I seem to have things back on track. Thanks guys.

chris

Good deal, which advice did the trick?

 

[Seth1913]

I’m having this same issue with inconsistency in sizing 6.5-300 wby. Below are my problems so I’d like to know what your solution was.

Brass-1x fired wby
Rcbs full length die with expander ball
Unique case lube
Using a mitutoyo caliper with a Sinclair #25 bump gage I measured a fired case and zeroed it there and found a consistent zero with all fired cases then when I went to size I set shoulder bump to .003. Some would size perfect some .002, .004, some wouldn’t size at all. Not sure what I did wrong. Press is an old Hollywood turret press but I haven’t had this problem sizing 30-30 or .243 win brass

 

[jjohnsonElknewbie]

I ran into this recently while FL resizing a couple hundred once-fired cases in one session. After I got into a rhythm, I failed to notice that the die got loose in the turret. It backed itself out as I was working. I started at SAAMI spec., and it backed out far enough that some of the last cases wouldn’t chamber. Moving forward, I will make sure the die is screwed in tight with each new case.

Redding press and dies.