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Old May 17, 2012, 06:43 PM   #1
WWWJD
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Time to start bumping shoulders?

I've got to the bottom of my "once fired" brass bucket. I've noticed that on about 1 in 20 or so, the round chambers significantly more snug than the others. The case lengths are all in spec, so I'm guessing that my shoulders are starting to creep. .308, fire formed. Only got the one rifle.

I've been using a Lee Collet neck sizer along with a redding bullet seater; was using a redding neck sizing die, but a quick check of concentricity turned me off of it. This combination's been working well for me. May be a dumb question, but is there a die that will just bump the shoulder, and leave everything else alone? Or is there a die that will bump and neck size like the collet, and leave the body alone? Or should I just try something else? I'm going to the hardware store tomorrow to buy a spacer so I can start pulling some measurements.

I'm to the point that whatever I load will be twice fired brass, so inherently this problem is just going to be more prevalent as time goes on.

Thanks guys,
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Old May 17, 2012, 06:56 PM   #2
WWWJD
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I found this one; Forster Precision
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Old May 17, 2012, 07:55 PM   #3
jason75979
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That's what I bought as well. I haven't yet fired the gun so I can not attest to its worthiness.
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Old May 17, 2012, 08:39 PM   #4
Bart B.
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Niel Jones makes bushing dies that size only the neck and set the shoulder back. I tried one with different bushing diameters for different neck wall thicknesses on .308 Win. cases. I quit using my Neil Jones die as I got better accuracy with full length sized cases in a die whose neck was lapped out so I wouldn't have to use an expander ball. Redding and RCBS now make full bushing dies that do that.

You'll eventually have to full length size your cases anyway. Their body diameters will get very close to the chamber diameters. As there's no such thing as perfectly round cases or chambers, the case will interfere with the chamber and won't freely center in the chamber shoulder when the firing pin strikes its primer.

I've got the Jones die and a set of .308 Win. bushings from .331" up to .337" (or something like that) in .001" steps. If you're interested, I'll sell 'em for half of retail plus shipping.

http://www.neiljones.com/html/micro_dies.html
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Old May 17, 2012, 10:54 PM   #5
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I've got a Redding FL sizing die. What are the odds that I'd be able to do a bump with that, without body sizing (much).... I'll have to try it tomorrow and see what happens. I'm a bit wary; the FL and neck sizing dies (redding) were both pulling the necks off center. Terrible runout. Shoulder on the Redding maybe, then chase with the Lee Collet.
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Old May 18, 2012, 12:43 AM   #6
Sport45
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Quote:
I've got a Redding FL sizing die. What are the odds that I'd be able to do a bump with that, without body sizing (much)....
I'd say next to none. By the time the shoulder in the die contacts the shoulder in the case the die has pretty much completely swallowed the case.
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Old May 18, 2012, 05:56 AM   #7
WWWJD
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Meh. That's the bitter reality pill I didn't want to swallow. Darn. I'll have to buy something. That's awful.

UPDATE: I went ahead and ordered the Forster die and an LE Wilson case gauge. It was bound to happen.

Last edited by WWWJD; May 18, 2012 at 11:23 AM.
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Old May 18, 2012, 04:53 PM   #8
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Get a LNL headspace gauge, and FL sizing dies, and bump the shoulder to what your chamber dictates.

This was the first article I read when I started reloading, and while neck-sizing with custom dies may be the way to go for match shooting, I full length size, have no issues with brass life, and life is GOOD with full-length sizing, every time. The Larry Willis gauge is top notch, if ya got the dough.

http://www.larrywillis.com/

http://www.hornady.com/store/Lock-N-...h-Body-1-Each/
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Old May 18, 2012, 05:05 PM   #9
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Quote:
but is there a die that will just bump the shoulder
Here is the die you want to use if you are using the Lee collet die for neck sizing: Redding .308 body die link

Yes it does size the body while bumping the shoulder, but you will need to do that from time to time anyway. When the shoulder moves forward, the body also increases in diameter. It is the same basic phenomenon.

Any way you use a FL sizing die will always work the neck more (translation - neck splits unless you anneal) due to the action of undersizing then expanding, and the runout will be greater.
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Old May 19, 2012, 06:14 AM   #10
Bart B.
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WWWJD, why are you so dead set against sizing fired case bodies?

For what it's worth, for sometime now, the benchrest folks winning matches have been full length sizing their fired cases slightly reducing their body diameters and setting their shoulders back a bit. High power match winners and record setters have been full length sizing their fired cases since the 1950's. Top competitors tried neck only sizing .308 Win. cases back in the early '60's when it was first used in rifle matches; didn't work as well as full length sizing. Sierra Bullets' uses full length sized .308 Win. cases in standard chambers testing their bullets up through 180 grains for accuracy; their best match grade ones shoot no worse than 1/4 to 3/8 MOA in their 200 yard test range.

Some folks full length sizing their .308 Win. cases get dozens of reloads per case with max loads in SAAMI chambers. I've got as many as 47. And annealing was never done. Full length bushing dies without neck expanders were used so the case necks weren't work-hardened with that neck-bending expander ball.

What load are you using that makes a few cases chamber significantly more snug than the others after being fired only once?
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Old May 19, 2012, 07:52 AM   #11
WWWJD
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Bart,
I really don't have a scientifically proven reason not to FL size. Based on just what I've read, it seemed to make sense to neck size only. I've only got the one rifle, and I'm doing it for case life. The variance in chamber fit I'm attributing to the brass; Federal brass doesn't get good reviews, but it's what I've got. Could be in my loading process as well, though I call myself being meticulous as I can. Measuring fired cases, there's nothing that leads me to believe it's a chamber fit problem. I'll know more when my case gauge shows up I think. Most of what I'm using came from Federal GMM, but there's 60 or so mixed in there that were Power point, Nosler, etc. The thought occurred to me that the brass from those rounds may be a little different from the rest.

I'll figure this stuff out eventually!! Or not.
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Old May 19, 2012, 07:55 AM   #12
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I am in the same camp as Bart B. Full length size your cases and life will be that much better.

Function will be better as the case will no longer be a interference fit. One very real consideration is that an interference fit in the chamber will cause stiff loading and will likely be such an interference fit on extraction that you will need a cleaning rod to extract the case.

God help you if you are firing these cases in something like a 308 Garand or a M1a. If the bolt has to stop, to crunch the case to the chamber, you have created the ideal conditions for an out of battery slamfire. This much case head sticking out of the chamber, incidentally this ballooned case was sized with a standard Lee sizing die, this much case head exposure was similiar to the 30-06 rounds that caused two out of battery slamfires in my Garands.

One of those out of battery slamfires blew the receiver heel into my face, shattering my shooting glasses and cutting my face.



As for case life, bump the shoulder back about .003" and your cases will last a long time. I took one set of LC Match cases 22 reloads in my M1a's , never had a case head seperation, and I was bumping my shoulders back .003".

Every competitive shooter I know, and several of them are National F Class Champs, full length resize their cases.
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Old May 19, 2012, 08:07 AM   #13
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Well I'll definitely keep these points in mind guys. I've gotten awful spoiled on this 'no lubrication required' neck sizing with the Lee collet. I wouldn't say I'm hellishly bent against FL sizing yet though.
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Old May 19, 2012, 08:46 AM   #14
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I reload .223 Rem for a bolt action. I use the collet die a lot. The thing is I FL resize the brass every 5 firings. After each firing I do the paper clip test to check for pressure rings. The Lee FL Resizing die works just fine for me. I get half MOA or better on a crappy day out of my Savage.
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Old May 19, 2012, 01:00 PM   #15
Bart B.
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WWWJD, based on just what most people read, to them, it make sense to neck size only. Problem is, most people do not understand how a rimless bottleneck case fits the chamber when both before and when it's fired. The benchrest competitors neck only sized for decades. But when bullets finally shot accurate enough to show how the tiniest difference in tools and processes change accuracy they get, they finally decided to stick with proper tools and processes for full length sizing.

I credit a handfull of high power rifle shooters (shoulder fired, in three positions from 200 to 1000 yards) of telling folks why their rifles shoot as well as the do. People with the last names of Tompkins, Gallegher, Jensen, Hull, Tubbs, Bernosky, McCann shot rifles that when tested in machine rests produced test groups back in the 1960's and 1970's smaller than current long range benchrest records with full length sized cases. Martin Hull, top competitor and Sierra Bullets' ballastics tech (early 1950's to late 1980's) shot thousands (millions) of rounds of ammo testing their bullets for accuracy. He learned early on that proper full length sizing methods produced the best accuracy. Many folks know of his favorite comment on resizing cases such that they fit the chamber for best accuracy; "Resized cases should fit the chamber like a **** in a punch bowl." Lots of room around the case body and neck.
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