RCBS "X" die - any users?

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relodr36

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I recently bought an RCBS X die in .223 caliber,hoping to reduce case length growth for ammo fired in an AR-15.
Does anybody have any experiences with the "X" die,that you would be willing to share?
Thanks!
 
Good New I think

My shooting buddy shoots competitively in the military matches at the club bought a RCBS X die several years ago and loves it. He has not had any problems with it at all.
What I do not understand is the instructions tell you to trim the case .020" under maximum case length before using. If the cases only grow .001" per shot you would be getting 20x reloads per case. This might be the limit of case life for a .223.
Any other comments. I would also like to know more.
Centerfire
 
I have one and thought it would eliminate trimming. It does. But it does not eliminate chamfering. And if you tumble polish or the case growth is being stopped by the die, your chamfer quickly goes away.

Because I trim and chamfer all in one operation, I end up trimming every other reload or more anyway.

Saves me nothing.
 
Cases aren't going to last long enough in an AR to make it worth the effort if cases need to be rechamfered anyway. I must be getting old and cranky, but I can't see a big advantage if cases have to be trimmed 20 thou short and rechamfered every couple of firings.
 
I have been using a regular RCBS full-length die.
Measuring purchased once-fired Lake City 09 Nato brass,before and after full-length sizing(with the die touching the shell holder,under load),I see case length growth of 0.003"-0.007". This is with the regular sizing die.
I haven't fired any of my reloads that were trimmed per the X-die instructions.
I was also wondering if Hornady's elliptical sizing button or a Redding carbide button would reduce case growth.
 
The expander button doesn't lengthen the case on sizing, it's the (over?) expanded brass being squeezed back down that needs a place to go. The only place it can go is up to the case mouth. That's why cases lengthen on FL sizing.
 
I used one for awhile loading for my M1A. Didn't see any real advantage to it and I don't think that it helped me any making straight ammo. Just my $.02 worth.
Mark
 
X Die

relodr36 said:
I recently bought an RCBS X die in .223 caliber,hoping to reduce case length growth for ammo fired in an AR-15.
Does anybody have any experiences with the "X" die,that you would be willing to share?
Thanks!
Click to expand...

Use this die loading 223 for prarie dog hunting, shooting in Remington 700 bolt gun. Were re loading on a dillon 650.
We have to trim to length about every 5 times reloading a case (Winchester Brass)
Maybe some saving in time?? I think its more hype than true benefit.
However their an OK die. We have had no problems with it.
Load about 2000 rounds per year of 223
My 2 cents worth
CLP
 
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relodr36 said:
Boyd,
I don't have any way of measuring it,for this caliber.
Click to expand...

If you want to get as many firings per case as practically possible a tool like the Hornady (used to be Stoney Point) "headspace" gauge which measures the length from a place (hopefully the datum line) to the head of the case is very helpful. A set of dial or digital calipers and the gauge set (a body and several inserts (the body and inserts MAY be sold separately) are all that's required. Bumping shoulders for a .223/5.56 fired in an AR back 0.003" will work and prolong case life. If the cases are sized as much as possible with the FL die you'll see head separations before they should happen.

The only time this isn't true is if the chamber is WAY oversized. I had a factory barrel back in the '70's with a chamber so large that if cases were FL sized they suffered head separations after 4 firings on average, 5 maximum. It was a bolt action too.
 
Larry,
I've got the RCBS precision mic for the .220 Swift and 30/06 and find it is pretty helpful in controlling how much the case is sized.
I should get one for the .223. One of Wilson's case gauges might be useful to check once-fired military brass to sort out the ones that have been fired in a SAW.
I think a lot of run-of-the mill AR chambers are close to the upper limit on tolerances to prevent slamfires,so full-length sizing will likely shorten case life.
 
If you don't FL size for an auto-loader you're likely to have slam fires from the cases not chambering freely. Maybe I'm just a coward, but the idea of things going bang with the bolt not locked doesn't light my fire.

The X die is supposed to FL size the cases anyway. There's a difference between sizing cases back to minimum factory dimensions and bumping the shoulder back 3 thou to achieve easy chambering. I have one FL die that sizes cases for my AR and .223 bolt rifle at nearly the same setting (O ring under the die lock ring and marks on the lock ring to line up with a line on the press body. The die has to be screwed into the press ~¹⁄₈ inch farther for the AR which is about 0.001" or less. That's in a factory Bushmaster chamber.

Neck sizing for a autoloader is a good way to have new facial piercings IMHO.
 
Thanks!

Thank's for the tip on the Hornady guage.I already have the adapter and the bushing kit is pretty reasonable.Sure is cheaper than the RCBS precision mic.
 
I bought the X die for 8x57 bolt gun. Haven't used it enough to realize any differences from a f/l die.

I tried the Lee collet die with my AR 223, and the rounds wouldn't fully chamber. Backing them out was a lot of fun too.

I went with Redding bushing die and my brass survives pretty well. LC is pretty tough and can last several firing, although I tend to run about 1 grain below max charges for most loads. Even with the factory primer crimp, the LC makes for some accurate loads. Most of my "match" ammo is Remington.

Ejecting the brass in AR will tear up the brass, so I have avoided buying expensive brass. I did pick up some Nosler brass to try.
 
Larry Elliott said:
Cases aren't going to last long enough in an AR to make it worth the effort if cases need to be rechamfered anyway.
Click to expand...

They need to be rechamfered after every other firing when you use soft-jacketed bullets like J4s, Noslers, Bergers, etc. If you are just running milsurp ball, then they never need chamfering.

Some lots of brass, I'm working on 10 firings out of an AR. I expect 20 firings from my brass.
 
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