Will a steel sizing die increase brass life?

C

chipguy23

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Hello all new to the forum!
I have a question I cant seem to get a definitive answer to. I’ve been reloading for awhile now, I know all the benefits of carbide pistol dies and use them for every one of my cartridges I shoot.
With my 460 S&W I’ve been using Hornady brass, and on my fourth reload I had a case head separation. During my inspection of the brass before that reload I didn’t see any signs of imminent separation and was surprised it split on just its fourth reload.
My question is if I use a steel resizing die will it increase the brass life somewhat? I know the steel die won’t size the body nearly as much as a carbide die would. Thanks for any advice.
 
It depends. If the hypothetical steel die was tapered slightly such that the brass sizing close to the rim was just enough to allow the case to enter the chamber and the brass mouth was sized slightly smaller to ensure good bullet fit, then yes. Since a simple carbide sizing die ring is short, the case is sized to the same diameter all the way down. Which also means the brass close to the rim is sized more than necessary.

Redding offers dual carbide sizing ring dies in several straight wall cartridges to "overcome" the issue. But they don't offer one for the 460.

I load for the 454 Casull and have noticed the same issue. I use a two step sizing process that might help with the 460 as well. I noticed that my RCBS carbide 454 Casull sizing die was sizing the brass rather small. So I measured the carbide inserts on a few 45 Caliber sizing dies. The RCBS 454 Casull carbide insert measured .466". My RCBS 45 Colt carbide sizer also measured .466". But my Hornady 45 Colt carbide sizer measures .470". That .004" makes a noticable difference.

So now when loading for the 454 I first size (full length) with the Hornady die. Then I follow up with a partial size using the 454 die, sizing just slightly below where the base of the seated bullet resides. With this method the cartridges fit better in the cylinder and a finished round is nearly straight and uniform from top to bottom.

One potential issue is the length of the 460 case (1.800"). The inside of the Hornady sizer allows about 1.76" before crushing the mouth, so that should be just enough to accomodate 460 brass (when you include the rim and shellholder dimensions).
 
I have handgun brass that I've sized in carbide dies for more reloads than I can count. I actually have some 357mag brass I bought in the 1980's that I'm still using. If your brass is separating it's most likely caused by the gun/cylinder rather than your sizing die. Pardon me for asking this, but you say "split" and "case head separation". Are you saying that the brass is cracked down near the base of the case or up where the bullet goes into the case (the rim)? I'd suspect your cylinder has too much play front to back or the chamber(s) are somewhat oversized. Properly sized brass in a handgun should last longer than four loads. Some of my stuff in my .357max has been reloaded at least fifteen times and it's pretty high pressure loads. Can you post a pic of the case?
 
I'd chalk that up to a bad piece of brass. Personally, I sold my carbide .45 Colt dies and bought a set of RCBS steel dies because of the slight taper built into them that BBarn alluded to.

Don
 
Years ago I read an article where the author recommended short stroking the sizing die on straight walled revolver cases to reduce working the main body of the cartridge case. It also kept the bases closer to "as fired" diameter, which was supposed to help line them up better in the cylinder. They called this neck sizing.

I tried this with some 45 Colt cases, sizing down just past the seating depth of the bullet. Seemed to work well, however I saw no major change in accuracy or case wear. But I had no problems before that either.

Might be an idea to try if maybe your brass is a little on the small size and your chambers are near the big side.

Hope it helps.
 
There is something called a 'Hesitation Ring' in some brass.
Once the case forming process starts it MUST progress in one smooth stroke.

There is a die body that forms the outside of the brass case.
There is a pin forced down on a brass slug under tremendous pressure, so much pressure the brass becomes 'Plastic' or 'Fluid' and the brass is forced up around the pin inside the die body.

The press CAN NOT 'Hesitate' in the stroke or the brass will develop a 'Hesitation' ring in the brass.
Brass with Hesitation rings will fail in very short order since the brass is two entirely different densities, and as a quirk of the process, they normally happen just above the floor of the powder chamber.

The press exerts a crap load of force to get the brass moving, but the brass 'Jumps' when the pressure reaches 'Plastic' point and will try to hesitate waiting on the pin movement to 'Catch Up', a hesitation ring is formed.

Forming die lubrication changes can cause this hesitation ring in modern production, just a hiccup in the process.

You CAN NOT detect a hesitation ring with the usual paper clip method since there is no 'Dip' or 'Groove' in the brass, and polished brass shows no hesitation ring.
A little corrosion (tarnish) on the case will sometimes show up the hesitation ring, since different densities of brass corrode at different rates, but most of us do our level best to keep cases from corroding!

A rolling pin press for brass is actually built with a 'Bump' on the actuators to the pins to keep brass moving during this initial stage of movement, modern presses use hydraulic pressure regulator to stop hesitation rings, but nothing is perfect...

I wouldn't make too much of this one failure, but if the same headstamp/brand of brass does it again, I'd consider culling those cases...
It's good you are tracking the number of reloads by head stamp, this is ALWAYS valuable to have!
 
Chipguy23,

That's too bad. It would have been interesting to section it and see what it looked like internally. I would check to see if that breaking point corresponds to where the nose of your expander stops when you expand and flare a case. If it does, the expander nose may be forming a corner there and be in need of some deburring and polishing.

Also, check in your chambers and make sure you don't have one with a groove or other tool mark defect corresponding to the break location.

According to the SAAMI standard, the 460 S&W cartridge case is a true cylinder with no taper. The chamber has a very slight taper of about 0.001", probably to make extraction easier. A steel die may have a similar slight taper for the same reason, but that's not the cartridge designers intention.

When I emailed RCBS about the size of one of their small base rifle resizing dies one time, they told me the diameter tolerance was ±0.002", which is rather larger than I'd expected. If the same spec is true of carbide sizing rings and is typical industry-wide, it might explain the difference from the Hornady die that BBarn measured. Lee rifle dies are usually on the wide end of the range. Call them and see what their 460 S&W sizing die diameter is made to. It may suit you better. Same with Hornady and Redding and Forster and Dillon. Dillon's are likely tight, as most of their dies are in order to ensure there's no stoppage in a progressive loading cycle, but the others may be looser fits. Call around and see.
 
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