Question - To full length size, shoulder bump, or just neck size???

[SOcalsurferx]

A little preface to my question, I have reloaded approx 300 rounds of 308 win now through my introduction to precision rifle cartridge loading and load development. As it stands, I have read and serached through what seems like every bit of information regarding this subject on the internet and in written books, but still have a few questions. So far I have only been neck sizing... I am using Lapua brass that has been fully processed and neck sized using redding .336" neck sizing die. I have read multiple conflicting accounts as to whether the brass shoudl be full length sized, neck sized, or shoulder bumped. My rig is a Surgeon SA with a MTU taper Krieger SS 24" tube. I had any difficulty chambering my reloads.

One side says not to full length size or even neck bump with a bolt gun. Avoid overworking the brass and exploit the benefits of the brass that is specifically fire formed to your chamber specs.

One side says you should full length size every time, no matter what.

One side says you should shoulder bump the case back by .001 - .002 each time.

As it is now, my recipe consists of full prepped lapua cases, 44.7 grains of Varget, Wolf primers, and 175 gr SMK's which leave the tube at approx 2,760 fps. I consistently get 5 shot groups of .400 or less.

Soo, what is the consensus with regards to sizing? Also, if I full length size using a redding FL die, should i run an expander through the neck and re run the brass through my bushing neck die?

Thanks in advance!!!!

All wisdom appreciated in the search of prefection!

 

[necchi]

If your getting 4's by neck sizing,,what's broke?
as in "If it ain't broke, don't fix it"

IMHO, you hit the answer yourself, the matter will be under contention till there is world peace.
If your lucky enough to neck size with no bump your brass will last longer,,and that's the simple factual gain. Nothing more.
Some have too bump,,
Others have too FL size,,
It's all an individual case (ouch) with each gun.

 

[Kenny474]

It's a similar subject as the "to use a brush or not when cleaning" argument. Everyone has their own opinion and regimen, and I imagine it will always be that way.

For certain guns you must full length size for reliability, such as an autoloader.
I full length size for my 06 auto, and necksize for my bolt guns, and only full length size when the bolt gets hard to close from hot loads.(that's after 5+ loadings, maybe more)

With the accuracy you are getting, I wouldn't even consider changing. The only thing I would do is anneal the brass on occasion.

 

[NorCalMikie]

If your fired brass will fit back in the chamber without and excesive bolt closing resistance, neck size and reload.
When the brass starts getting snug in the chamber, body size, (maybe every 4th or 5th firing) shoulder bump and reload.
Full length resizing of the brass just moves the metal more than you need to. The less you move the metal around the longer your brass will last. And a tighter fit in the chamber. JMHO, Mike.

 

[Laurie]

I'd heartily agree with all of the previous replies. There are two, maybe three, reasons given for full-length sizing. One: hunting (deerstalking / sporting as we'd say on our side of the Atlantic) rifles where easy and alweays reliable chambering and extraction in the field are vital (even more so with dangerous game rifles and loads where both slick chambering and fast extraction can be lifesavers). Two: slack / out of round factory rifle chambers - FL sized ammo often performs better in a poor chamber / barrel, becoming less of an issue today even with out of the box rifles as manufacturers improve tolerances, and not an issue at all with any well-gunsmithed custom rifle. Three: habit / tradition.

I've rather taken to Forster's bushing-bump dies, a bushing controlled neck sizer that also allows you to set the shoulder back marginally. Many people do very well indeed with neck sizing alone, even at the point where their cases are a crush fit in the chamber longitudinally, but the situation of some cases having marginal clearance against the shoulder, others just touching and still others being a slight crush fit needing the bolt's camming action to get closure is theoretically undesirable. Semi-autos or rifles without a good camming action on bolt closure are another matter entirely - there are a lot of broken M1As and M14s around due to case-chamber fit/headspace issues.

As someone said, if it ain't broke don't fix it. 0.4" or smaller groups is fine with the 175 SMK and makes a good all-purpose load at that MV. If you're prepared to spend the money, give Berger's 175gn and 185gn Target BT Long-Range bullets a try. They are superb performers and will see less wind deflection at 500yd and longer distances than the Sierra.

Laurie,
York, England

 

[SOcalsurferx]

Thanks for the great responses!!! I am very happy with the way this rifle shoots, now I guess I should stop worrying about it and get some more trigger time in to tighten up the groups more!

Thanks again!

 

[mikecr]

I agree with NorCalMikie
I have NEVER FL sized brass, and wear out barrels faster than brass.

If you visit forum, after forum, after forum, and look over problems posed with reloading, 99/100 of the time it's due to FL sizing.. This is because the only way to pull it off without issues is with custom dies -that account for just what non-FL-sizers have been all along.
You might also notice very few problems posed by those who NS only, with an occasional bump.

So the 'consensus' you seek might actually be held by the quiet of us.

 

[Shynloco]

I have to agree wholeheartedly with mikecr, except for the part about wearing out barrel's before brass. My 22-250 is a shining example of overworking brass by full length resizing each and everytime in order to allow for the bolt to close after firing due to liberal headspace in the chamber of the weapon. I have found that by "bumping the shoulders" a few thousands helps to keep my brass useable for twice that of full length sizing each time. That happens for me especially when using Winchester Brass which I have been only getting on the average about 4-5 reloads before signs of head separation, whereas around 8 - 10 reloads when bumping the shoulders. I believe mikecr hit on it specifically when he mentioned "custom dies" that are honed to match your specific weapon. You may be aware, but you can take your reloading die (regardless of make) and sent it to the manufacturer along with three fired casings and they'll rehone your die to match the weapon and the problem will be solved. Most do it for free or may charge a few pennies for their work. Just something to consider. The fact remains though, the less you "work" your brass, the longer it lasts.

Good luck and have fun reloading!

 

[Tozguy]

German Salazar's article in The Rifleman's Journal of June 9, 2010, titled Basics: Resizing - Case dimension changes is good reading on this subject. Can be found at-
http://riflemansjournal.blogspot.com

 

[SOcalsurferx]

Thanks for the responses everyone! Going to get some trigger time tonight!

Tozguy - Good article thanks!