using bushing dies

[bradleygt]

Hello, Looking for some input. I want to start shooting tactical matches with a 308. So I'm looking for the most consistent load. I heard good thing on Redding Bushing dies so I thought I would try one. I bought the full length bushing die. Went through all the stuff to determine the right bushing. My goal was to have loads with .0025 or less run out. Well not having very good luck. Out of ten loads 3-4 might make it the rest .005 or more. I tried two bushing to get to the final neck size this was suggested by Redding. I have tried Hornady Match brass, Nosler Match brass and Winchester brass. Bought a tool from Sinclair to check neck thickness. Have sorted them down to .0015 neck thickness difference. I have better result using my Foster full length die with the expander ball. I'm using a new Foster Co-Ax press. Would like to some thoughts. Thanks

 

[BuffaloBill]

Have you tried turning the necks to make sure the wall thickness is consistent? The neck bushing would align the OD of the neck but the bullet will align with the ID. Just a thought.

 

[nosualc]

Just a shot in the dark, but make sure your bushing has a little play in it as it allows it to center the case (you should be able to hear the bushing rattle a little bit if you shake the die). Good luck.

-nosualc

 

[TAB]

I use a Redding bushing neck die in a Co-Ax press for .223 Rem and have pretty good luck with it. Case run-out is typically .002" or less. I'm using a bolt gun, when the case shoulders need set back (which is not often) I use a body die.

You mentioned "Out of ten loads..." Is the .005" your case run-out or cartridge run-out?

Have you checked with Redding? I've had good luck solving problems with their tech staff.

TAB

 

[Keith Glasscock]

I have been around the block with my bushing dies. In my 223, they work great. In my 308, not so much. That is, until I got my chamber specs and brass lined up.

Here is the problem:

With my old chamber (.343 neck) I would get brass out that needed to be sized with a 330 bushing (Winchester). That meant squeezing down the diameter .012" I would get all kinds of neck runout - up to .007" total indicated runout (TIR). When I tried other brass, I got better results. Federal brass required only .005" of sizing and gave me better runouts. The best runout I was able to get was out of a Hornady FL size die. Just by chance (or design) the Hornady has a .3285" neck diameter (really close to what I needed anyway - .0025 neck tension). That is what worked for me with that chamber.

Now I have a chamber with a .335" neck (brass comes out at .3332-.3334 - probably a little under 335) and I use a 330 or 329 bushing. The result is runouts on the order of .0005 to .0010 with the same die and bushing.

In my experience, a bushing die will give runouts of anywhere from 1/3 to 1/2 of the amount of squeeze being put on the brass. There are some things you can do to help yourself out and improve runout.

First, use the least neck tension that you need to get the job done. Unless you are using coated bullets, .002 will be plenty even for tactical.

Second, clean all of the junk off of the neck before you try to size it. 0000 steel wool was all but made for this - just make sure to wipe any steel fibers off before sizing - I tumble my brass after the steel wool and before sizing.

Third, use plenty of lube, and be consistent about it.

Other tricks:

Try trimming your brass to square the case mouths before sizing them - just be sure to chamfer them before you size.

Make certain that the bushing can float a little in the die. On my Forster dies, I apply a little bolt grease to the top of the bushing so that it can slide against the stop more easily.

You can step-size the brass if you have a lot of squeezing to do. It helps some, but doesn't fix everything. You will still have some big runouts at times.

 

[bradleygt]

Thanks for all the replys. Some of the replys I have tried and the others I will try.
Thank Brad

 

[Killshot]

I'm sure you have, but......you did remove the expander-ball from the Redding bushing die and replaced it with the decapping-pin keeper, right?

 

[brian427cobra]

Brad I shoot in precision rifle matches, I'm a Military trained jet mechanic not sniper, my 308 has a .342 neck, with Win 308 brass I neck size it down .003 at a time, the final size is done with a .331 bushing in a FL die, then I use a expander mandrel to push the neck thickness irregularities to the outside, for this type of shooting we don't get all our brass back, so Wincester is what I use, DO NOT neck size only for this type of match shooting, our ammo must chamber every time, hits are hits and misses are misses, we get no sighters, sometimes we are not allowed to check zero, I suggest you have good DOPE on your rifle from 10 feet to 1000 yards, yes I said 10 feet.