Another reloading question

168bergersapper

168bergersapper

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So if you've read any of my last post on this forum you'll know I've been trying to iron out some issues that I have encountered in my attempt at precision reloading. But if not, my previous problem was with case neck run out. I was experiencing run out as high as .008 or .009 thou. I have since reduced this to a consistent
-0.002 with a change in neck bushing and some neck turning. Now however I'm getting inconsistent bullet runout anywhere from .002 to .007 thou. I've only loaded 18 cases thus far trying to test various things to help mitigate this but to no avail. I understand if I have .002 neck run out I'll most surely have some bullet but come on! .007 thou. Anyway as before I really appreciate any advice that may help. Thanks fellas.

I'm using
- Lapua .308win brass neck turned and trimmed to 2.002"
- k&M control depth chamfer tool
- Redding competition series bushing die and seater
 
Competition dies don't have an expander....

Try a friends PRESS and load a few dummy rounds and measure....there is a chance things aren't running true.The shell holder could even be the problem....
 
My runout probs disappeared with Lap brass, regular annealing, Lee collet neck size, "M" die expanding to 2 thou. neck tension, and seating with Redding or Forster micrometer competition die.
I no longer even check for runout. All are 2 thou. or under, most under a thou..
(really helps at 950 yards)


Every now and then the Redding body die keeps things chambering smoothly.
 
You can optionally get an expander with the comp. dies.

How much of the neck are you resizing? I personally get good results sizing no more than 3/4 of the neck. Sizing more than that could deform the neck/shoulder and affect concentricity. Lapua brass has very consistent neck thickness and I never had to neck turn. Bullet runout never exceeds 0.0015.
 
I did away with presses altogether and went to the Wilson dies. This along with neck turning gave less than a thou consistently.
 
try seating your bullet, bring the ram down a bit, rotate the cartridge 180 degrees, then run it up into the die again. or try partial seating of the bullet, and the same technique of bringing the round down enough to give a half rotation and finish seating the bullet. experiment with your sizing technique as well. chances are that one of your reloading components has an excessive tolerance.
 
The comp dies capture the case before seating is initiated. I'm likely wrong, but I could see that rotating the case could possibly helping with concentrity, but I think that would wreak havoc on your neck tension if you're already having Concentricity issues in the first place.
 
Where on the loaded round are you measuring the runout?
Do you have about a caliber length seated in the neck or less?
If using the expander button when your resizing are you lubing the inside of the case neck?
If your measuring near the meplat that would give the highest readings.
Should be on the ogive where the bullet would contact the lands - that's where most measure from when stating they have 1 or 2 thou runout
 
.284 said:
Where on the loaded round are you measuring the runout?
Do you have about a caliber length seated in the neck or less?
If using the expander button when your resizing are you lubing the inside of the case neck?
If your measuring near the meplat that would give the highest readings.
Should be on the ogive where the bullet would contact the lands - that's where most measure from when stating they have 1 or 2 thou runout
Click to expand...

I'm measuring about half way up the ogive from the meplat.
I'm definitely seated far enough into the case. I'm using Berger 175 OTM
I'm also using the K&M expanding mandrel before I neck turn but that's it. And I do lube it.
 
Last edited:
barsik said:
try seating your bullet, bring the ram down a bit, rotate the cartridge 180 degrees, then run it up into the die again. or try partial seating of the bullet, and the same technique of bringing the round down enough to give a half rotation and finish seating the bullet. experiment with your sizing technique as well. chances are that one of your reloading components has an excessive tolerance.
Click to expand...

I've tried rotating after a complete seat but not half seat - rotate - and seat the rest of the way.
I'll go give this a try right now see if it helps.
 
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