While I was in South Africa a few weeks ago I managed to pick up a new sizing die that's made there. I actually got to meet the man behind the magic through an introduction by a mutual friend. I got to see and use the die I was extremely impressed. So impressed I had to have one. They have a standard (though still super precise) die for SAAMI/CIP chambers and a "Custom Collection" version for those of us with more persnickety requirements. I got the custom collection version made to my specs while I was in country. I also got to have a nice chat with Jaco, the man behind the magic, and have a nice long chat with him about how the things were made and some general chit chat. Turns out, the level of precision they craft these with apparently required a ton of effort just in building testing instruments so they could measure sufficiently precisely to hold their amazingly tight tolerances.

The box is nicely jointed and finished wood.

Inside everything is set in custom cut foam. Given the precision, cost and purpose, you'll want to keep things orderly and clean and not bumping into each other.


All of the little bits from the die kit.

All the mechanical stops are in the die itself so it's a little different to use than I'm used to but dramatically different. It does mean the die can move from press to press without readjustment of the die. One tiny bit of note, it's not a standard 7/8" die body. It's a 1"-14TPI body so a different press bushing is on order for my RCBS Rockchucker and I'm having a local machine shop cut one of my Dillon tool heads for it.

The benefits for me are setting of neck tension & head spacing very precisely. It came with 5 neck bushings at .0005" increments so I can now get consistent tension between lots of brass. Normally I neck size only until I have to bump the shoulder back but that causes issues with rounds that decides they won't chamber without a lot of force to close the bolt. Slows me down in a match and breaks my concentration. There are click adjustments on the die for the shoulder bump which I've seen and measured to be extremely accurate. Want to knock the shoulder back .0015, 3 clicks. It works just that easily.

The cost is fairly high (retail is almost $600 shipped to the USA) but real precision costs real money. If I can't magically be a better shot, I can pay to take a little more slop out of my ammo.

It's a little different in how it works to other dies I've used in one nifty respect, the body sizing and shoulder bump happens first without touching the neck, then the neck sizing operation happens as its own part of the stroke and neck sizing depth is controlled by virtue of a shim pack that adjusts it in .0020" increments.

They have a seating die coming out too which I've already asked for a copy of. I have a couple buddies using one of these already and they're reporting very good things. As soon as my press bushing and tool head are done I'll be doing a vigorous bit of comparison testing against my existing Redding dies both in group sizes and dimensional consistency. Yes I know other companies make custom dies but when you see how these work you'll understand... click adjustable headspace, consistent .0005" adjustments, easy transport between multiple presses without re-setup of the die, etc.

While my seating die is being engraved I've taken some time to wring out the sizer properly. Accuracy of neck sizing is perfect. Accuracy of shoulder bump has been perfect as well. Both things one would expect from a 550 dollar die.

Actually that precision turned out to be a little bit of an issue in a way. Some of the brass I was working with hadn't fully formed to the chamber (the brass was a mix of 1-fire, 2-fire, 3-fire  and 4-fire) and was coming in short. I thought there might be a die issue so I smoked the shoulder on one and found out it wasn't making contact with the shoulder bumping part of the die. Then instead of assuming all cases were uniform length to the shoulder, we measured with the included headspace gauge and figured out what was going on. It needed really 3 firings before pushing the shoulder was going to be required or possible anyway. Hooray! So not an actual die issue so much as a brass issue and a me lumping lots of brass together and forgetting about that detail.

Along the way I had to have some machining done. My RCBS shellholder clearly wasn't parallel between the top face where the die contacts it and the flange that holds it into the press ram. I took that over to my machinist and had him tinker on it. That made setup a little easier even though it wasn't totally necessary. It eliminated me using a feeler gauge around the circumference of the shellholder to verify where "touching" actually was. I still had to use a feeler to verify that I was at "just touching" versus -.0005 or +.0005.

Once we got it set up against the included gold master, then the fun times with lube selection came up. The body section of the die is very tight and the base of Coach's 6xc chamber is not. I was getting a rough time running brass in and out of it with stickiness. Hornady One-Shot case lube was not going to be it. It wasn't slick enough. Fine in my Hornady/RCBS/Lee/Lyman/Redding dies but not in this one. I then tried pad applied RCBS case lube which definitely was better but still not as slick as I thought it should be. Next we tried Imperial Sizing Die Wax which takes longer to apply and is messier but it offered no stickiness on sizing. That was a recommendation from the manufacturer and it turned out to be a good one.

To check neck tension we grabbed a bunch of 6XC and .243AI brass and I pulled the body/shoulder sizer out of the die and ran with just the neck bushing. My .243AI necks are thinner than our 6XC necks by about .003 total. The outside diameters were identical as one would expect but inside diameters showed the expected .003 difference. The little shims that are included for setting the neck sizing depth allowed for coach's neck setup and mine to be accommodated with ease and repeatably. Coach sets his necks up so the last .020 isn't constricted so it rides the walls of the neck area in his chamber. I size my necks all the way to the shoulder/neck junction. Pull one shim, switch sides for it and done.

Everything being so precisely machined is helpful but the real money was the click adjustments for the shoulder bump. It required buying a much better quality micrometer to be sure (I was using cheapies before but they were showing variability so I upgraded) what I was getting but once that came in all questions were answered. Definitely getting .0005" per click of shoulder push back. We'll be running some grouping tests this weekend and then shooting a match with ammo loaded with this die. Between the super consistent neck tension and shoulder push I'm expecting an incremental improvement specifically in SD's and more consistency of chambering ease. No more having a few cases that needed the bump and didn't get it making for hard bolt closure.

So we have initial results. I'd like to thank you all for the views on my video.

http://www.youtube.com/watch?v=niwCR3SmiBA

We will be testing this die set more over the next year. This is out of my pocket and out of my own curiosity. I have the credit card bills and had the arguments with my wife to show for it. I must caution, because of some things people seem to have in their heads, that this isn't ever going to make a 1" gun into a .5" gun. Anyone suggesting such a thing is either a fool or a liar. What you should be expecting is to reduce variability in your ammo which reduces things like flyers & SD's. Effects on group size, maybe small ones should be expected as a normal effect of better consistency but because barrel harmonics are involved there so heavily it's best to keep your hopes in check and out of the land of silliness.

I set up a partially blinded experiment with unfired, 2x fired and >5x fired cases. We (Coach and I) sized up 50rds of each from my Exact die and 50 of each from Coach's Redding die and tested that in Coach's rifle. Coach's rifle has somewhere over 1900rds down the pipe now which is a concern as you'll see soon. We set the ammo up identically in everything from components to neck tension. We ran 10 shot groups which were composed of 2 non-consecutive 5-shot groups fired at the same aim point. Coach loaded, packed and labelled the ammo boxes (labels are "1" and "2") and didn't tell me till after the shooting was done which was which. I pulled the rounds from the boxes, logged data and called the target to engage while coach did the shooting. That way neither of us knew during shooting which ammo was being fired at any given time. That was the best way I could think of for me to pull out experimenter induced bias with a research team of 2.

The result of the first accuracy test was null. That is to say that the numbers difference in average group size was not outside the level of statistical noise. The exception was with brand new brass. It always shot more consistently than reloaded brass and so I removed those results from the full data set due to the noise they introduced. We also weren't meant to be testing new brass as that would not apply anyway but I wanted that data for another experiment I've been running. This is all precisely what was expected. I expected no big result (but certainly hoped for one) in accuracy simply by going to full length resizing and having extremely consistent neck tension and headspace.

Because the result is null though, we'll re-run the experiment on that rifle just before we replace the barrel, just to verify the results reproduce reliably. We also did some velocity testing as part of that and there was no statistical change in average velocities or SD's except that in the new brass loads but it was more consistent set to set. Why pull the barrel? The rifle used for that run of the experiment now has ~1900 rounds through it in 6XC with a single load spec (38.5gr H4350, F210M, Norma brass, 115gr HBN coated DTAC). The load is mild; generating only 2800fps, but we know that that barrel is within a few hundred of being pulled on principle; if not actual need, as far as match work goes and it may not be capable of the repeatable accuracy that might show up with the Exact die. So, we'll try another barrel. A new one. Actually, a new two! So stay tuned, there's more to come.

In September I purchased 2x new barrels which I got as blanks from the same production run (from Black Hole Weapons). I purchased a new custom reamer in 6XC that produces a chamber that is very tight to the dimensions of the Exact die. Thankfully you can order a reamer with any number of customizations and it's still the same price as a custom reamer with just 1 custom dimension. Unfortunately it takes weeks for such a reamer to be made. Over the winter I handed the whole works over to a gunsmith friend of mine that also makes ultra-precise gauges as a business. So, he has the equipment and skills to set up barrels that are truly as identical as we could make them and identical enough for a useful experiment to come out of it despite a sample size that's extremely small.

Anyway, I got both barrels cut, profiled and chambered identically. It was at great cost too. The cost to set each one up was double what I normally pay him to set up a barrel for me for each barrel with over 15 hours of work on each one. These are our new match barrels for the next 2 seasons too. Coach and I will be shooting from the same ammo box so we can share data. Maybe we'll pick up a few points on same-day wind calls.

We did have a non-null result and from a different direction, which I also predicted. That was that with loads that were sized with my ExactShooting.com die we never had trouble closing the bolt. It was, in fact, always exactly the same effort. On the cases that we sized on the Redding neck die that Coach uses bolt close effort was either not much or a TON. Some post-facto testing later on with coach's FL die showed the same random bolt close effort. This is obviously due to random headspacing which means that Coach's FL die probably needs a thou or two buzzed off the bottom. Irrelevant though because we're testing what's available out of the box and his FL die out of the box didn't cut it so I suspect that a lot of FL dies out there may be a little long or short and aren't sizing things like people think they are.

That is only the results from a well used barrel. We will be running this exact same test using the 2 newly set up barrels. One will be on the same gun (Coach's match rifle) while its twin which now has just under 400 rounds on it is on a different my "Hot Dog Gun" match rifle. I don't expect any difference but I could wind up being surprised. The new barrel on Hot Dog Gun is extremely accurate so far, better than Coach's rifle on its first day. We've already developed a load for the new barrel that runs things a bit faster (2980fps) so hopefully with more pressure more differences might start to manifest.

One of the cool things about the ES die is you can pull the body/shoulder portion out and still use the neck sizing portion which itself is easily adjustable for neck tension and neck sizing depth. When you start getting hard bolt close you can dial in .0005" or .001" or .0015" or whatever amount of push-back on the shoulder with an easy click adjustment and know it'll give that to you exactly. We'll be running a neck tension accuracy test here real soon. We'll see if .0005" increments makes real differences on paper. First though, I'm ordering some brand new brass for that test.

Cost is fairly high for these dies but not unprecedented. That's true but, beside the point. If you have the money then that's not an issue anyway. Functionality is THE issue. It's perfectly functional and makes it super easy to dial in neck tension at .0005" increments for those really finicky loads, to dial neck sizing depth at .020" increments and to dial how far back you actually push your shoulders in .0005" increments. They'll make one to a reamer print too. How precise are the dies? Well I had my machinist do some gauging to see if they were that precise and he was pretty darned impressed.

For benchrest guys and F-class guys, I think this is really packing the potential to up their game a bit but only because those guys tend toward having done everything else already. BR and F-class are the only places I can think of of offhand where neck tension and headspacing are tightly controlled by the shooters both routinely and with an obsession rarely seen.

Is it going to help joe sixpack? Well no, to be honest. Joe doesn't know enough to get the potential benefit to begin with. Owners of this die will 100% want to keep their brass sorted by number of firings. They'll know about what spring back is and why it's important to them and a lot more. They will be the type that can't deal with unexpected 5's instead of 0's or 1's in the 4th decimal place of a measurement. The right owner for this die is someone very much like me in the respect that they are prone to setting up narrowly defined experiments and to analyze the statistical data that results before forming opinions. They're nerds.

For Coach and I the benefit is being able to share ammo and ballistics data in a match, not running out of time anymore on match stages due to bolt cycling problems, not overworking or insufficiently sizing the brass and being able to make subtle adjustments with truly minimal effort as precisely as adjusting a tactical rifle scope.