Shoulder bump

Until u go hunting and can't chamber any or very few. I speak from experience when I was very young and had little reloading knowledge. Everytime for me. And I run every hand load thru my gun before I put it into my hunting round box.
Yeah similar thing happened to me and why I switched from neck sizing to only full length sizing. I was on my 3rd or 4th firing with 7mm-08 and went to chamber a round and the bolt was pretty tight closing.
 
Likewise I don't resize unless the fired brass tells me to resize. I have a Rem 5R .308 and I'm on my third firing on Peterson brass that needs no resizing yet. I generally randomly pull 10 pieces of fired brass from my bucket of spent brass and check them.

My .280AI needs to be bumped after each firing (again Peterson brass).
 
I "bump" every time!

I load a bit on the warm side and expect the brass to fill the chamber…..maybe it will or maybe it won't shrink back consistently. If nothing else….after the bump……the brass is all consistent.

And, my rifle is a "hunting rifle"! Years ago, I had rounds that I found to be tight to chamber while hunting…..don't want that again!

At that time I was just "kissing" the shoulder…..now they get the "bump"!

I'm also not shooting at the distances that some of you shoot, plus I'm satisfied with my 1/2" to 3/4" groups @ 100. Grouping, or lack thereof, and my lack of skills limit my shooting at game to within my "time zone"! memtb
 
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I bump the shoulders enough to get the web dimension for easy bolt close, Full length Die dimensions vs chamber dimensions.

I wish that a company made a series of Web sizers graduated in .0005 increments, this way you could control your shoulder bump better.
 
How often should you bump the shoulders when your resizing brass? Specifically brass that has only been shot in the gun your reloading for.
Every time I size my brass it gets the same process. The die is set at a 2 thou bump from fired, and the necks get sized back from fired to give 2 to 5 thou neck tension. And I anneal every time as well with an Anealezz. IMO consistency is key to accuracy. I like to feel the cartridge on the last inch of bolt closure. Tight is good for brass longevity. Less stretch. If you want the bolt to close easier go 3 thou bump.
 
Many years ago, when I was into the "just kiss the shoulder" method, as mentioned, I experienced some that were "TITE" to chamber on a hunt. Maybe the "kiss" was too light, maybe the near zero F hunting conditions slightly altered the chamber dimensions.

After that experience, I had to make a decision …..carry a 1 lb "dead blow" hammer when hunting as to quickly chamber a "TITE" cartridge 🙀 or "bump" the shoulder!

As I carry a lot of gear when hunting, I opted-out at carrying the hammer! 😜 memtb
 
If they start that short and are not expanding into your chamber to be tight you will have head separation problems sooner than later. Something is wrong with your chamber specs or the brass to begin with. Even if you bump .005 or .006 you should get a tight bolt close on a fired case, if you're not I would be concerned.
It might take a firing or two for them to grow to the chamber. Even if everything is to spec.

not every case/brass combo will grow .005 or more every firing….
 
It might take a firing or two for them to grow to the chamber. Even if everything is to spec.

not every case/brass combo will grow .005 or more every firing….
You got that right. I've measured fired cases and I've often been surprised at the results. I've had fired Peterson brass spring back to a size less than new! No kidding. This in a bone stock Rem 5R in .308 and 6.5CM.
 
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Every time I size my brass it gets the same process. The die is set at a 2 thou bump from fired, and the necks get sized back from fired to give 2 to 5 thou neck tension. And I anneal every time as well with an Anealezz. IMO consistency is key to accuracy. I like to feel the cartridge on the last inch of bolt closure. Tight is good for brass longevity. Less stretch. If you want the bolt to close easier go 3 thou bump.

This is how we reload our Match brass for benchrest shooting, but if you try this on hunting loads, you have to keep the pressure down or else you will have great difficulty raising the bolt handle on top end pressure loads. I could not dare use this method above with my 7 Mag or my 7 STW loads that shoot very tiny groups, or I would be beating the bolt open with the top of a fence post or limb what was handy.

Also, it is good to know the dia of the chamber at the web vs sized or new brass dimension.

You really want your brass to extract without resistance after firing.

The subject of chamber dimensions vs die dimensions vs brass dimensions is somewhat complex where compromises are often made.

You also do not want various amounts of pressure needed to close the bolt on a loaded round, they should always feel the same or else you are changing the harmonics of the barrel.
 
I full length resize, with integral neck bushing, after every shot. I bump the shoulder no more than .002." I can adjust my sizer .001."
I send my brass to be annealed after about 6-8 firings.
I don't feel the case resisting bolt closure. I have no problems with stretching or separation. I inspect each case after each shot.
 
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