Cocentric bullet seating

The Redding dies are one of the best out there. When Sinclair endorses them, they must work! Using the Redding sizing dies with their floating sizing bushing, along with their competition seating dies will usually yield no more than .001 run out. It is critical that your bullet starts out straight into your barrel (assuming your chamber, throat, etc. are in line). Tests have shown that run out is more critical than several other factors. /ubbthreads/images/graemlins/laugh.gif
 
TGScott

if you have a neck turner cut take a cut down the case neck about .050-070 down and about .002 thin.

When fireformed next time that cut will be on the inside of the case and allow you to start the bullets in straight which is the problem.

Old BR trick from Pindell of PPC fame.

BH
 
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TGScott

if you have a neck turner cut take a cut down the case neck about .050-070 down and about .002 thin.

When fireformed next time that cut will be on the inside of the case and allow you to start the bullets in straight which is the problem.

Old BR trick from Pindell of PPC fame.

BH

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that is a neat idea Herm--do you do this at all? Is this just a flat-base fixer?

Kraky--no need to even tighten the decap/exp rod--let her loose, and it will find its own center on exit /ubbthreads/images/graemlins/wink.gif

JB
 
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Kraky--no need to even tighten the decap/exp rod--let her loose, and it will find its own center on exit


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I third that statement. It is the easiest and best way to eliminate runout when sizing. I also use a floating sizing button.
 
take your sizing die and see if you can push the decapping pin to one side a little with your finger (yes you can with it locked tight)now take a resized case and see if you can bend the neck over with your finger (NO YOU CAN NOT)
SO THE SIZING BUTTON IS NOT CAUSING ANY RUNOUT IN YOUR CASES.
 
HERE IS ANOTHER REASON FOR NOT GETTING BULLETS STRAIGHT WITH A COMPITION BULLET SEATER THE SLIDDING BUSHING THAT I HAVE I MEASURED IT, IT IS LOOSE IN THE DIE AND THE HOLE IN IT IS ALSO A LOOSE FIT ON BULLET AND CASE NECK BOTH SO I DON'T USE IT FOR THAT REASON (JUST WASTED MONEY)
 
axial symmetery and Bersin

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I do believe the barrel can and does straighten out the bullet

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the physics of this is well understood and measured. It's not the simple bullet straightening out - it's how the bullet deforms into the lands as it seals - you want this deformation to be axially symmetric.

Check out the Bersin runnout tool - I'm going to get one

All the BR guys I know only use custom made dies (from fired brass)
Skip Talbot - the world champ at 1000 yard 50 BMG shooting had a good tip - when he seats his bullets - if there is any runnout he rotates the cartridge 120 deg then reseats it (repeat again if necessary)
I think Skip also uses the bersin tool
bench_rest_tool.jpg
 
ALL dies with expander balls need tuning

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ALL dies with expander balls need tuning

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Y not do what all the BR guys do - remove the friggen thing?
 
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