X-die experiment

[tommag]

I recently aquired a contender with a .223 bbl. Since I had only a .223ai die and a small base .223 set, I decided to order the RCBS X-die.

I have never tried to see how many loadings I could get out of a case before, and decided to see if the X-die would give longer case-life.

I started with a new Win. case and loaded it near max with 25.8 grs of 844 and CCI450 primers, topped off with some 55 gr fmj. The process was slow, since I only have a Rockchucker press.

After 30 loadings, there is still no sign of thinning at the web. The case grew about .010 and stopped growing. The only flow I found was in the primer pocket.

I set the die up to set the shoulder back .001".

I imagine that the neck would split before any case-head seperation with cast, due to the flaring of the neck. Maybe an annealed vs. non-anealed test is in order.

[1hole]

Tom, can you tell us just what it is about the X die that limits stretching?

[tommag]

The expander rod has a larger diameter portion that hits the case-mouth at the end of the stroke.

[Johnch]

LOL I found out a long time ago 3 things about the 223 X die

1 A small bit of gravel in the case will break the expander rod
But RCBS will replace it for free with just a phone call

2 With the die properly ajusted
I can even shorten range brass back to standard length that was fired from a full auto SAW and is streched slightly

3 It stays in a tool head for the Dillon 550
As I load a lot of 223 blasting ammo from time to time

John

[tommag]

I had to re-start at 35 loadings. Somehow I got a primer in katty-whompus and buggered up the rim getting it out of the Lee hand primer. Still no sign of case head seperation. I need to try the small base die for a comparison.

I wish I had a turret press, it would speed things up immensely.

Maybe it's not the X-die, but rather the minimal shoulder set-back that's giving me the long case life. At any rate, it's nice to not have to trim cases over and over.

[Ken O]

I'm sold on the X-Dies. I hate to trim, and these dies work as advertised. I have them in .260, 308, 30'06, 223. I wish they made them for the 7.5 Swiss, I'd buy one in a heartbeat.

[1hole]

Tommag - are you saying the expander rod has a sharp diameter increase on the upper portion that sort of forces the mouth of the case back a bit during the sizing step?

[tommag]

Tommag - are you saying the expander rod has a sharp diameter increase on the upper portion that sort of forces the mouth of the case back a bit during the sizing step?

Yes, it has a step on the mandrel that either forces the case back a bit or stops it from growing.

[Johnch]

I use the 308 X die for 30 - 06 also

That saves a few $ if you load for both

John

[lovedogs]

I, too, have wondered about trying X-dies. I've found my best case life with all bottle-neck brass in both Contenders and bolt rifles by adjusting my FL dies to only size the cases to fit the chamber. I make this measurement using RCBS Precision Mics, which I really like. Is the X-die adjustable enough to allow only partial resiziing or do you have to full-length in it? I've wondered if you could adjust to only partial resize if you might have an unsupported shoulder and wind up crushing it down.

[lovedogs]

Oh, I also forgot to ask... what are you shooting with FMJ's? With all my .22 caliber rifles and Contenders I shoot lots of prairie dogs and coyotes but wouldn't think of using a FMJ. I use mostly Speer 52 gr. HP's, Hornady 50 gr. SX's, and Hornady 55 gr SP w/cannalure.

[tommag]

lovedogs, The X-die is really ths same as anyother die, except for the step on the de-capping rod. I measured the shoulder with the precision mic.
As to the FMJ, I used them for this test only because I had a 1000 of them that I could think of no other use for. I stopped at 50 firings of the second piece of brass because I got tired of the test. The area between the flash-hole and the interior of the brass seemd to be getting a bit thin, but this is only my perception. I was using a primer-pocket uniformer to clean the pocket.