how to prevent bullet run-out?

Longwalker

Longwalker

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I have discovered that an accuracy problem with my .35 whelen is probably due to badly aligned bullets. I used new unfired 30-06 brass, and ran it through my Hornady .35 Whelen full length die to open the necks. Used a Hornady die to seat as well. My rifle shoots 4" groups with this stuff, and less than 1" with factory rounds. Looking for possible causes, i found that bullets in loaded rounds wobble visibly when rolled on a table. There even appears to be some run-out with bullets seated in factory .35 whelen brass, just not as bad. So what did I do wrong?
 
As tedious as it sounds, you might try to go in steps from .308", to .311", to .323", to .338", to .358". You might also benefit from taking the spring that retains the shell holder off the ram and replace it with a rubber "O" ring, thus allowing the shell holder to float and find its own center. You can do the same with the expander button on your resizing die, put a small "O" ring under the lock ring of the stem and this will allow the stem to find its own center.
 
Boomers right, as usual, there are also quite a few diff. in line bullet seaters out there, Vickerman,Forster, etc. You may want to try a new neck size only die, also.
 
It sounds like your resizing has left your neck with a loss of concentricity, either related to the shoulder or necks. I am curious, have you checked the run out, after seating bullents in the cases you have already fired?

I would guess that issues of case concentricity should be solved after you have fired them, as they will form to your chamber.

You will also want to follow the 'twist and seat model' outlined by others to help compensate for the tendancy of the seater to push the bullet out of line.

Finally, I looked and could not find anyone who makes 'inline' seater for the 35 Whelan, do any of you guys know of one?
 
Did you check the brass? I check for consistent case neck thickness and case neck concentricity before adding bullets. I believe this helps.
 
Thanks for all the input so far.
- 350 Mag, I forgot about the "seat partway and twist" method, have used it in the past for more accurate .22 hornet loads. I'll try that.
- good idea GSoD, but I don't have a case concentricity gauge, wasn't planning to buy one unless absolutely necessary.
Here's another thought. I was reading a new loading manual I just bought yesterday, Modern Reloading by Lee. He claims that expander balls should have some parallel shank area in order to facilitate concentric neck expanding. The Hornady die has an elliptical expander ball, could that be the main culprit?
 
Well - I had the same problem a few years ago - turns out a grain of powder was stuck in the shell holder in the rim channel, causing the case to be eccentric.
 
As a quick substitute for a conc. guage, you can use something as simple as a strip of 1/2x1/2 angle. Stick the case in the "pit" of the angle and measure between the neck and inside wall of the angle iron with your calipers. Just rotate the case 1/4 turn or so between measurements. l can only assume you have calipers though. Not a very high tech solution but it can give you repeatable results.
 
the rcbs casemaster is pretty inexpensive and does the job good enough for my needs. check it out, may save some sanity.
 
Fireform the brass first. Expanding the neck that much with an expander ball will lead to seriously out of whack necks.

You can use the cream of wheat/cornmeal method to expand/fireform without the use of bullet or die.

I bet the fired brass is true - should be as the rifle shoots well.

I love the Lee collet neck die and have not been able to measure any runout caused by this die. Some conventional expander ball dies can be out of whack. The only way to know for sure is to measure each stage to see where the runout is coming from.

I really don't expect to see much problem making ammo concentric enough to shoot MOAish.

Try shooting ammo using the recently fired brass and see if things settle down. I bet they do.

Jerry
 
I cut runout in my 300WM to nearly nil by adding a few extra steps to the sizing process.

First I run the case through an universal decap die.

Second it's into the sizing die with the decapping assembly removed. This sizes the neck down but does not expand the neck afterward.

Finally I expand the neck by running the expander ball into the case.

This process lowered runout considerably. If I was making 338-06, 35 Whelen or 9.3x62 our of '06 brass I would also expand the neck in steps using different expander balls until I got where I wanted to be (if I didn't just go out and buy factory brass).

As well, when I set up my sizing die I put a ratchet socket on top of the ram and press gently against the bottom of the die as I screw it in. I don't know if it makes a difference, but in my mind it ensures that the die is square to the ram.

YMMV.
 
One easy step not mentioned yet, is to rotate the case 1/4 turn after the first pass over the expander and full length resizeing. After turning the case, resize it full length again.

As far as useing different sized expanders, I've tried that and it seems to be a waste of time, especially if you're lubeing the inside of the case neck before expansion.

I size for 3 different 338-06 rifles and cured the runout problem by rotateing the case dureing the resizeing cycle.

bearhunter
 
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