375 H&H die adjustment

wislnwings

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I resized a batch of 375 H&H cases last night and I'm getting a very slight bulge in the neck, just before the shoulder. The empty cases still chamber with no problem. These are Federal nickel cases. I've been loading for over 20 years and never run into this. Do I have my full length resizing die setup wrong or is this a problem with the nickel cases? Any input is appreciated.
20160723_164820.jpg
 
Is it the dreaded donut? When the round is fired brass moves towards the mouth of the case. When you resize the expander pushes the excess brass to the outside of the neck and the donut forms.
 
are you lubing the inside of your necks.
 
It shouldn't be a problem with nickel or Federal cases. I've resized a bunch of Federal nickel 375 H&H Magnum cases and have never had that problem.

Are you full length resizing; i.e., does the shell holder contact the bottem of the die when resizing?

I also don't believe lube has anything to do with it as 375 H&H Magnum cases need very little inside the neck lube.
 
I also don't believe lube has anything to do with it as 375 H&H Magnum cases need very little inside the neck lube.

A small amount of lube yes...but definitely lube. Expander binding in neck can compress neck causing a bulge but it sounds like die needs adjusting..
 
Full length sizing and the shell holder is about an 1/8" from the die at the bottom of the stroke.

With ram raised all the way to the top of the stroke, screw the die all the way until it contacts the shell holder. Then try sizing another case. I think you may not have the die in far enough and the bulge you're seeing isn't a bulge at all. Rather the portion in front of the bulge has been properly sized while the "bulge" is neck brass which wasn't compressed.
 
As Phil states, I agree. If there is a gap between the die bottom and the shellholder, you are not full length resizing. In fact in the manual it tells you to touch the shell holder with the die, then turn it down a bit more if you want true full length sizing. Looks like you are partial resizing, which is fine, you get longer case life but for trouble free feeding, full length sizing is best.
 
I was taught to back the die off about 1/8" but I found this didn't always hold true, on my 375 I snug the die down and barely back it off with good results, now reading Sestoppelman's post I'm going to snug the die down tight,,Another Day,Another learning experience
 
It all depends on what one wants to accomplish with the die setting. Partial resizing is great for case life and the theoretical "sized to the chamber" fit of the brass, but for slick feeding for hunting rifles, full length is probably better. In my case I use new brass for hunting trips and run each round thru the rifle before leaving home. I have had dies that would not touch the shoulder unless I went full hog on it, touch the shellholder and crank it down a bit more. Every chamber is different and dies vary as well, sometimes its the shellholder, lots of variables. For most of my general shooting I like to just feel the shoulder engage the chamber for a slightly snug fit, that way I know there are no headspace issues and brass last longer. If you full length resize every time and set the shoulder back every time, case life is shortened somewhat. With belted mags which are notorious for short case life, I try to set the die the same way and headspace on the shoulder instead of the belt.
 
With ram raised all the way to the top of the stroke, screw the die all the way until it contacts the shell holder. Then try sizing another case. I think you may not have the die in far enough and the bulge you're seeing isn't a bulge at all. Rather the portion in front of the bulge has been properly sized while the "bulge" is neck brass which wasn't compressed.

The man knows what he's talking about.
 
Looking at your pic, the bulge looks to be about the same 1/8" up from the base of the neck/top of the shoulder, as the 1/8" gap between the Shell Holder and bottom of the die. You're only partially resizing the necks and none of the body of the case. Pretty much what @sestoppleman said. Correct me if I'm wrong.

I've used F/L dies to Neck Size before, but will adjust the die with a Feeler Gage off the Shell Holder. It works, but ain't quite the same as using a Neck Die.
 
What puzzles me is that is the first time you've seen it after loading them before with the die out of adjustment.
 
With ram raised all the way to the top of the stroke, screw the die all the way until it contacts the shell holder. Then try sizing another case. I think you may not have the die in far enough and the bulge you're seeing isn't a bulge at all. Rather the portion in front of the bulge has been properly sized while the "bulge" is neck brass which wasn't compressed.
+1. Size your H&H so that your sizing die juuuuuusssst kisses the top of the shoulder. You don't want to move the shoulder back more than .001-.002", so that you can headspace on that, rather than the belt. Headspacing on the belt will kill your brass life and stretch your cases unduly. Sestoppelman and Phil know what they are talking about. Once you are down to the top of the shoulder, you will have brass that feeds great and lasts a long time!
 
Another vote for dropping the die - looks like you're only partial neck sizing, so the bottom of the neck isn't getting attention. I initially thought it was a doughnut too, but that's way too big and too far forward to be a case stretch doughnut.

Like others mentioned, use a headspace bushing to measure your shoulder datum line, and bump the shoulder back ~2thou (1 works if you're keeping your chamber spotless). I'll second the principle to load belted mags the same way you do non-belted, bottleneck cartridges - headspace them on the shoulder. Your cases will thank you for it. When I'm hunting game which can't/won't kill me, I only neck size my cases in 300 and 338wm - just kissing the shoulder - and reserve the full length sizing for positive feeding in what might be DG loads.
 
Except for neck sizing I have always seated the base of the die against the shellholder and then down about 1/8th of a turn. When you pull the ram handle down you feel a slight "pop" against the shell holder. That's the method I use for bottleneck cases.
By the looks of the picture of the 375H&H brass the expander ball didn't go all the way down the case neck.
 

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