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Cheap runout repair tool

I recently saw a video on this forum showing how to shock at bullet back into alignment. The tool setup is nearly $400 (plus the cost of a good divorce lawyer if I spent it right now). I wanted to see if it works and if I could duplicate it with what I already have. Yes, and yes! Cost was $0.00.

A tire gauge that has a nice smooth radius. And a 50 gram weight that is slightly rounded at the top. I did over 20 so far and it works perfectly. I checked the runout on a Sinclair gauge and marked the spot where the bullet was at it's lowest. I supported the bullet tip and tapped it with the weight at #2. (I'm talking a very very light tap, not enough to bend anything). The runout at #3 was a little over .003" before. After straightening, the runout on the neck, point #1, was just over .0005". Half way to the tip, point #3, measures a total runout of about .001". I also check to see if anything was bending at the tip, point #4, and it still measured just under .001".
RUNOUT-FIX.jpg

After 20 I'm starting to gain confidence in this method. No failures or problems so far. Every one straightened usually on the first attempt. This is resized & neck turned Lapua .308 brass. Before I use to try and bend the bullet straight but gave up because it is very easy to go overboard and it also loosens the necks. Nothing seems to be bending here. The dimensions on the neck didn't change as far as I can read with a .0001 micrometer. Maybe it shocks the surface contact area and allows it to relax. Even with a Redding competition seating die, there is still some runout from time to time. I usually set them in 2 steps rotating the case 180 degrees in the press.

The worst I found so far was over .004". After straightning (3 attempts with a bit more force each time, still very light taps) #1 was at .001", #3 at .001" and #4 at just under .002". So far I don't see any marks or making the bullet tip out of round even though the lead doesn't extend clear to the tip (about .200" down inside) and it's unsupported copper.
 
I recently saw a video on this forum showing how to shock at bullet back into alignment. The tool setup is nearly $400 (plus the cost of a good divorce lawyer if I spent it right now). I wanted to see if it works and if I could duplicate it with what I already have. Yes, and yes! Cost was $0.00.

A tire gauge that has a nice smooth radius. And a 50 gram weight that is slightly rounded at the top. I did over 20 so far and it works perfectly. I checked the runout on a Sinclair gauge and marked the spot where the bullet was at it's lowest. I supported the bullet tip and tapped it with the weight at #2. (I'm talking a very very light tap, not enough to bend anything). The runout at #3 was a little over .003" before. After straightening, the runout on the neck, point #1, was just over .0005". Half way to the tip, point #3, measures a total runout of about .001". I also check to see if anything was bending at the tip, point #4, and it still measured just under .001".
RUNOUT-FIX.jpg

After 20 I'm starting to gain confidence in this method. No failures or problems so far. Every one straightened usually on the first attempt. This is resized & neck turned Lapua .308 brass. Before I use to try and bend the bullet straight but gave up because it is very easy to go overboard and it also loosens the necks. Nothing seems to be bending here. The dimensions on the neck didn't change as far as I can read with a .0001 micrometer. Maybe it shocks the surface contact area and allows it to relax. Even with a Redding competition seating die, there is still some runout from time to time. I usually set them in 2 steps rotating the case 180 degrees in the press.

The worst I found so far was over .004". After straightning (3 attempts with a bit more force each time, still very light taps) #1 was at .001", #3 at .001" and #4 at just under .002". So far I don't see any marks or making the bullet tip out of round even though the lead doesn't extend clear to the tip (about .200" down inside) and it's unsupported copper.
Many bullets have runout from the chamfer on the inside of the neck Larry
 
You don't have to worry about the bullet bending. The neck on the case is going to move.
If it does, it's not measurable. I pulled a couple and the force needed using a press collet die seems the same as any other. The amount of force is very minor. maybe the same as dropping the 50 gram weight less that 1/4". The hard surfaces shocks the metal. Bending them in a fixture just slightly over the bullet diameter even a little loosens the neck tension. I guess a fixture that was a snug fit over the neck may be better. I tried that for quite a while and screwed up several that I had to resize and reload again. This is experimental but so far seems to work very well. I'll know more when I go through a couple hundred.
 
I just don't want to mess with seated bullets

Rather deal with crooked bullets than disturb neck tension

I can keep them under..003 and.for me that is good to go
 
You don't have to worry about the bullet bending. The neck on the case is going to move.
I just took a couple empty cases that have been annealed (but fired at least once afterwards) and used the same force to tap on the open end of the necks with no bullet inside for support. They did not bend out of round, nothing detectable with a micrometer. Of course, if you smack them with a hammer, they will be bent and ruined.
 
Same as your doing it will work checking
Never had success with straightening .
Larry
Just finished 100. Screwed up 2 that I will pull and resize. I went past center and it showed the low spot opposite of the first. The biggest problem is tapping them too hard. It takes a very light and consistent touch to get good results. I got them all at .0015" or under. Seems to work. I'll test fire them the next un-windy day. Would be nice to have some kind of way to measure the seating, release pressure. Maybe use a scale on the press handle.
 
You don't have to worry about the bullet bending. The neck on the case is going to move.

I just finished 200 rounds and have some ideas. The cases aren't being impacted hard enough to bend anything. I think it's a combination of tolerances that may be causing the runout in the first place. The last 100 were Hornady cases and only had about .001" interference fit. That may not be enough. I have measured some Hornady Match bullets that are .0004" out of round, some Sierras at .0002". There are tolerances when the necks are turned. Nothing is ever perfect. I measured several cases that the neck turning cut all the way around. They were .0006" - .0009" runout in the middle of the necks. I don't have a small ball mic to get inside to measure the thickness but using a caliper and taking multiple readings, the thickness may vary by .0005". This drawing is exaggerated to show what may be happening. If due to a stack up of tolerances the bullet's larger diameter is horizontal and the case's is vertical, there could be as much as .001" difference in fit and tension. So this would be a reasonably snug fit when seating but the bullet is tight horizontally and has a lot less tension and (possibly next to none) in the vertical plane. The bullet could be slightly angled out of alignment with the case. I noticed some that took almost no force to move sideways. You could lightly tap the case at the neck with a pencil and it would do it. I noticed on several, especially these Hornady that had looser necks, that the low side measured on a runout gauge moved 180 degrees to the opposite side after lightly tapping them.

Bullet.jpg

First thing, I'm going to stop using the .001" fit. I only did on the 208g loads that were right on the edge of showing pressure signs. Tighter necks may not help but couldn't hurt. I reloaded 9 of the Hornady and 6 had more than .002" runout measured on the bullet after seating the same bullet. At least, I was able to get 79 out of 100 at .001" or less and the rest at no more that .002" runout.

Here is a link to the video showing this method. The guy is an excellent shot so I can't argue with him.

If anyone has any ideas, I'd like to hear them.
 
I have 2 observations :

1 - if your run-out is at or slightly over .003", then I'd say you have little to gain here.

2 - if your loaded ammunition actually looks like your 'hypothesised' image, then there are other issues to address, rather than chasing total run-out.

Just MHO, YMMV.
 
Curious as to why one would spend so much time trying to fix loaded rounds instead of load them correctly the first time?

I would if I could. I usually use Lapua brass & neck turn to .0125" thickness. I use a Forster benchrest full length die and a Redding competition bullet seater. Every care is taken to get better results. I have used the resizing die with and without the ball and it makes no measurable difference. Out of the last 100 reloads, (38) had .001 or less runout, (36) more had between .001 and .002 and (26) were between .002" and .003" or a hair over. There are no donuts, the cases are chamfered with an RCBS VLD cutter. The primer pockets are equalized and the flash hole is deburred on the inside. The bullets are seated to within .001" measured just under the maximum diameter, not from the tip. Powder charges are within .02 grains. Cases and bullets weighed and sorted. Still no matter what, some will have more runout than others. I have loaded over 60% having under .001" before. Don't know what else to do to make them more correct. I contribute it to production tolerances (bullets, brass, and dies) and to how springy the brass is. I do anneal every 4-5 loadings.

I'm not dwelling over minor differences but like to have things the best I can make them withing reason and this is basically experimenting. That's how we learn.
 
I have 2 observations :

1 - if your run-out is at or slightly over .003", then I'd say you have little to gain here.

2 - if your loaded ammunition actually looks like your 'hypothesised' image, then there are other issues to address, rather than chasing total run-out.

Just MHO, YMMV.
It's not as bad as the picture. It's overdone to show what may be going on. Like the bullets. I only had a few Sierra Match Kings to measure but they are as much as .0002" out of round on the bearing surface and some of the Hornady Match are up to .0004". And cases probably aren't perfect either when you start looking at them in ten thousandths increments. It the wide part of the bullets happens to seat in the narrow part of the case neck (maybe only .0002"), then the tension will vary around the diameter to some degree and most likely go unnoticed. Like you said, probably little to gain but if I can make them better, I will try.
 

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