Neck Sizing die....does that solve the problem - sort of ?

cloverleaf

Handloader
Sep 10, 2006
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So - in an effort to save you all some boring reading.... I will include a link to my original posts related to this question. Synopsis is as follows. My FN Mauser actioned 250 Savage was giving me trouble last summer. A combination of a reloading error, (3 grains or so over max), old brass and a rifle that will close with some effort, on the "no go" Gauge. Results- several split cases at the belt line. Smith did not suggest that the rifle was unsafe to shoot, but it is definitely over-working the brass to FL resize. I'm thinking about a Lee Collet die to limit the brass working. What are your opinions? Experience with the neck sizer/ collet dies. Thanks CL
 
CL, I have a Lee collet die that came with a 3 die set for 30-06. I've used it at times and it is a simple to use handy die. But, you will need to run them through a FL sizer anyhow after a couple loadings, so you will be just as well served setting up your FL die to minimally size your cases in my opinion.

If it's closing with effort on a no go gauge it's far from severe headspace. I had a rifle here that was close to .020. That would've closed on a no go and then some by quite a lot. Fireformed with a false shoulder then set my die to bump .002. At that point bumping just .002 it was no different than a minimally sized chamber. Brass lasted a long time.

You don't have to worry about a false shoulder......you're not that far out. Fireform then bump .002 with a FL sizing die. Sinclair I think it is makes a very cheaply priced piece to take shoulder measurements on brass with your calipers. You don't have to spend much money at all to have a way to measure it, I made my own.
 
Results- several split cases at the belt line.
Horizontal or vertical splitting. Picture of your split brass would be helpful. LCD would keep you from overworking your brass. You also could just set your FL die to just size the neck to.
ShadeTree has gave you sound advice.
 
I'll add this also CL. That Lee neck sizing only collet die can make for some very accurate ammo, and anybody can use it with the same results. BUT, that is only when used on a case that was fired in a spot on concentric chamber. If your chamber is off at all, and plenty are at least a little bit, that accuracy is only going to be realized if your case is loaded into the chamber at the same orientation in which it was fired. Otherwise you are better off having a little slop in the case from being sized down.

It could be just the ticket for you, but it's not a miracle worker with all things, and whether you try it or not, you need to learn to size your brass where you're just minimally bumping the shoulder because you will need to do that anyways after a couple firings with the LCD.
 
neck size only until the brass gets fully expanded . when it's fully expanded it will be a little tight to chamber , set up your full length die to only bump the shoulder about .002 on this fully expanded brass . it you set up on brass that is not fully expanded , you will be over sizing .
 
CL, Have you tried to anneal new brass and using the COW method to fireform to your chamber first? If not, I would start there and then go to FL sizing using a .002" bump.
 
Have you used a Lock N Load Comparator and check your headspace on your fired cases and your sized cases and see what the headspace is? Is your bolt closing tightly on those fired unsized cases? Try to close the bolt first without a fired case and see if it closes smoothly, then put a fired case in the chamber, then close the bolt, If its tight, then use the full size die, put the ram up on the press, screw in the die until it touches the ram, lower the ram, screw in the die about 1/ 16 turn, size it and try the case again in your chamber and close the bolt, if its still tight, gradually bump it in increments and try the fired / sized case again in the chamber and close the bolt, and keep screwing in the die /bump it doing it until it closes easier.
If you already have the tool, note the measurement, bump it .002" and chamber the fired case and see if it closes without a bind.
 
CL, I was having similar issues on my belted magnum cases. Switched to Lee collet dies years ago and have had great success (all I use now). Belted cases can be a problem due to design, but are workable. I get 8 to 10 firings out my belted brass using the following protocol: Lee neck size only, use Redding body die after abut the 3rd or 4th firing to get body close to original spec's for and bump shoulder back for chambering, anneal necks after every round (this really helps with case neck longevity-does not do much to help case life below neck/shoulder), never use FL dies on my brass. Good luck!
 
My 'Pennyworth' of thought.
Frankly I don't think the Lee Collet die is the way to go.
Far better to measure the 'Fired Case' headspace from your rifle & set your F/L resizing die to that dimension, bumping the case should back a max of .003" when F/L resizing.
Good luck anyway
 
Thanks all for your thoughts. The issue with this rifle has been difficulty getting the "bump" right, I think. . Separations occur around the base just above the web. In all my years of shooting this rifle with much of the brass fired in excess of three times I have never had a neck split. Just looking for ways to minimize the brass working. Newer brass is part of the answer. My guess is the chamber is not concentric and I'm sure the bolt face isnt square to the barrel. Sounds like the Collet die is not the answer to those problems. Thanks again, for the thoughts.
 
My guess is the chamber is not concentric and I'm sure the bolt face isnt square to the barrel.
Most aren't.
Although more bolts seem to be square than most chambers fact still remains there are a lot of sloppy machined actions that are sold, shot etc every day.
 
When you get your new brass, try jamming the bullet into the lands during the fire form. Use a reduced load. This should help with that initial stretch you are experiencing that is wrecking your cases. The Lee Collet dies work well. Eventually you will have to bump the shoulder with a FL die.

I have never figured out how to make a chamber that isn’t concentric, I’ve tried. The reamer follows the bore. If the setup is incorrect you will have an oversized chamber as the reamer will act as a single point cutter. It will still be concentric, just big. Anyway, I wouldn’t let that particular theory stop you from trying a Lee Collet die.
 
Thanks all for your thoughts. The issue with this rifle has been difficulty getting the "bump" right, I think. . Separations occur around the base just above the web. In all my years of shooting this rifle with much of the brass fired in excess of three times I have never had a neck split. Just looking for ways to minimize the brass working. Newer brass is part of the answer. My guess is the chamber is not concentric and I'm sure the bolt face isnt square to the barrel. Sounds like the Collet die is not the answer to those problems. Thanks again, for the thoughts.
Hmmm ... Dunno about this CL - personally I think unlikely.
A way to ensure your F/L resized case neck is as concentric as possible to the case body is to set your die like this:
Set your F/L resizing die in the press. Loosen the de-cap rod/expander, drive a lubed case fully into the die, withdraw the case until you feel the expander enter the case neck & STOP. While holding the ram/case under tension in this position TIGHTEN the de-cap rod.

Set up this way, I find when I measure with a concentricity guage, case neck run out from the case body is usually a max of .0005"-.001" & that's as good as it gets. At least you'll know the cartridge is right - as for bullet concentricity when seating... you now have a better chance of lower run-out.

Case separations are usually a headspace issue when resizing as previously mentioned @ #9.
Cheers & Good luck
 
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you need a way to neck size only , until the new brass gets fully expanded . a neck die , a neck collet die , or turning your full length die up so it only sizes most of the neck and none of the body , any of these should work . it could take 3, 4 or 5 fires until the brass is fully expanded .you will be able to tell when it's fully expanded , the bolt will take some effort to close on your ammo . if you try bumping the shoulders on brass that is not fully expanded you will be chasing your tail , your measurements will be all over the place and brass life will suffer . you will only need to do this for a few cases . I usually use 3, and fire them over and over , until they get tight . then set up the full length die to bump the shoulder .002 . after the die is set you can run all the brass through the full length die , even before it's fully expanded . if you size a piece of brass to much , grab another fully expanded case , raise the die a touch ,and start over . once the brass is sized to much , you have to fire it again to expand it .
 
you need a way to neck size only , until the new brass gets fully expanded . a neck die , a neck collet die , or turning your full length die up so it only sizes most of the neck and none of the body , any of these should work . it could take 3, 4 or 5 fires until the brass is fully expanded .you will be able to tell when it's fully expanded , the bolt will take some effort to close on your ammo . if you try bumping the shoulders on brass that is not fully expanded you will be chasing your tail , your measurements will be all over the place and brass life will suffer . you will only need to do this for a few cases . I usually use 3, and fire them over and over , until they get tight . then set up the full length die to bump the shoulder .002 . after the die is set you can run all the brass through the full length die , even before it's fully expanded . if you size a piece of brass to much , grab another fully expanded case , raise the die a touch ,and start over . once the brass is sized to much , you have to fire it again to expand it .

That is a good tip. I never thought about just using a couple pieces of brass then setting up my die. Don't know why I never did, that would greatly speed up the process.
 
I don't neck size anything CL, but what I do, is neck up brass and then run that same brass through my FL sizing die until it just closes on the case for the first firing (creating a small, false shoulder which supports the entire case on first firing). Controlling brass growth from the get go is my way of conserving brass life and keeping our hobby safe. After the initial firing, I measure my case with a calipers and a Hornady gauge, but you can use a 9mm, 40 S&W, 45 ACP piece of brass. The only think you are trying to do is get an overall measurement of the headspace. At that point I use my FL sizer until I have an average of .002 set back on the shoulder. Sizing in that way allows my brass to live almost forever, it maintains the same chambering in my rifle from first firing to the 20th firing, and allows that case to sit snugly in the chamber aligning the bullet to the bore as squarely as possible.

It is very easy to do and if you have questions I will detail them out with some pictures or whatever will help.
 
CL, let's keep this simple. The following is how I set up all my full length sizing dies. It's a a post I did a few years back, decided to save it in case someone needed it. FWIW, I has been saved as a sticky on another site. Anyway try my method and see if it solves your problem.
Paul B,

This is how I set up my sizing die for bottleneck cartridges.

1. Take a once fired factory round and blacken the neck and shoulders with a Magic Marker or Sharpee pen. Some people like to smoke the neck and shoulder, but I find the Magic Marker/Sharpee pen a bit better.

2. Carefully lubricate the case.

3. Loosen the lock ring on the sizing die and back off about two turns from when the die is set to touch the shell holder.

4. Size the case. Note where the marks are on the case and turn the die down about a half a turn and size again. Turn down some more, and resize again. What you are looking for is the marks on the blackening just touching the shoulder.

5. Clean the lube from the case and try it in the rifle. It may chamber just a bit on the snug side. If so, turn the die down ever so slightly, lube and size again. Wipe off the lube and try in the rifle. If it slides in as easily as a factory round, you should be good to go. If not, usually one more very slight adjustment should fix the problem.

6. Tighten the locking ring for the die and you're done. You have just set your sizing die up for a custom fit to your specific rifle, rather than a generic one size fits all guns.

Paul B.
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Your .250 Savage has significant taper, comparable to most military rounds. I would simply move your FL die up until the shoulder is not bumped significantly. This will likely improve accuracy, and will most certainly improve case life.

I load for a lot of military metrics, and this procedure is useful to attain maximum accuracy and case life from 7.62x54R, 6.5x55 and 6.5x50 Jap, especially with oversized chambers. In the case of one of my 7.62x54R rifles, even with a full 3 turns I am getting light contact on the outer radius of the shoulder, but accuracy is improved strikingly!
 
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