Forming 17AH Brass from 22 Hornets
By Alex Clarke
Sitting here at my desk wondering how to pass some of the cleanups for mistakes I’ve made in forming 17AH brass from 22 Hornet brass essentially has boiled down to trying to adapt the info from a previous manuscript of mine that appeared in Small Caliber News some years ago on forming 17M4 brass from 221 Fireball stuff. If a mistake can be made, I’ll usually find a way to make it, so writing things down seems to be a good idea. Best way to remember anything is to try to teach it to someone else, so here goes.
Essentially, as I went through the process of making the first 17AH brass, I followed the steps I had used for doing the job for my 17M4, just slightly modified. In both cases, it amounts to getting the cases formed without making a mess of the brass, and then getting the headspace correct.
Cooper’s diminutive M38 action is perfect for small cartridges like the .17 Ackley Hornet.
First, to get your attention, let me describe my good friend and master fox and groundhog hunter Sonny Pruitt’s experience with headspace. Sonny had come down to our farm to go fox hunting with my cousin Bobby and me. He was having a torrid affair with a Browning Micro Hunter in 22 Hornet, but when he arrived and saw my little Schnabel stocked Cooper Classic M38 17AH, I thought I was going to have to wrestle him to get it back. Long term end result was Sonny buying a TC Contender rifle and a 17AH barrel, the necessary forming dies and a Lee turret press. He didn’t much like the way the brass came out looking, but another good friend assured him that all of his own newly formed brass looked awful but shot great. Sonny isn’t a fan of single shot rifles, but was so impressed with his Browning Micro Hunter in 22 Hornet that he and Matt Crowder scoured the internet and found two of these little beauties (and another one for me as a result of another episode of fiscal irresponsibility on my part). Sonny and Matt both said that their 22Hs shot so well that there was no way that they would become “donors”. The game plan was for Sonny and Matt to have Bob Green convert them to 17AH. The process was intriguing for me to watch, but I will spare you, just this once.
Sonny had refined his forming technique while he had the Contender 17AH that his brass now looked pretty good. Unfortunately in his new Bob Green 17AH shooting fairly light loads he was having the cases separate at one of the bends in the 22H brass, leaving about half an inch of the brass in the chamber. When he walked into my gun playroom, I think could have bought the rifle for $75. We took some virgin 22H brass and ran it through my die setup and loaded a few pieces of brass with my standard fire-forming load. Sonny took the rifle outside and shot the bullet into the ground and then demonstrated extracting the piece of the case left inside of the rifle. (At this point I think I could have bought the rifle for about $50!)
How could this be? That round would have shot just fine in my little 17AH that Sonny had admired so. I was wondering if Sonny had a bad batch of brass. We reduced the load several times and finally with a much reduced load the case didn’t separate. Shooting that same load several times in that case finally made it form up with sharp corners. I was pretty slow on the uptake, but using the Stony Point (now Hornady) Cartridge Base to Shoulder gauge we measured the headspace and found that his chamber was enough longer than mine that it must be a headspace problem. I carefully marked my dies and turned them out about 10 thousandths and BINGO, with the full forming load, the cases stayed together. Opened them a little more until the brass was hard to chamber and locked them down.
(Note here that despite the fact that the 22H cartridge is “rimmed” and folks think that it should headspace off of the rim, doing so may cause just the problem that we had with Sonny’s rifle. Never assume that this is the right way to go as if the shoulder is pushed too far back it will overwork the cases at the shoulder and quickly result in case failure, or give the results we were having with separation on the first shot !)
The resulting brass and load in this rifle caused a sudden increase in Sonny’s demeanor, major increase in the bux it would take to pry it out of his hands, and a rifle that is scary accurate. Sonny went on the next year to kill 150+ groundhogs with this super piece, and the rifle has assumed “legendary” status.
With this introduction, let’s go into the particulars for acquiring and setting up to make the brass.
The very first thing you want to do is “detail” the cases. This means you at least deburr the flash holes while the brass is still at 22 cal. I sometimes leave uniforming the primer pockets until after the first firing.
Refer to the list at the end of this article for what you need. Admittedly, it is a Cadillac list, and reference to the archives of Saubier.com will let you know that some guys (Daryl and/or Alan from Georgia) can form 17AH brass from 22H in just one pass through their 17AH FL die, something I have never been able to do.
Since I have both 17AH and 17M4 rifles, and occasionally have fits of fiscal irresponsibility, when I bought my first 17M4 I also bought a turret press made by Fred Moreno of Sharp Shooter’s Supply. This handy little 3 stage press is a variation of the Lee turret press, using the Lee holders and licensed by Lee. I don’t think it is available any more, but Sonny has had good luck with the Lee version. Using it allows you to set up the dies once and never have to do more than just put the holder for the particular caliber dies in the press and go to work. Using a single stage press is almost as good, provided that you get the dies set once and lock the ring nuts in place.
First, set each die in the press, put the shell holder in the ram and bring the ram to the top of the stroke. Screw the each of the dies down to contact with the shell holder, and back it off an eighth turn (the standard thread on dies is 7/8 x 14), or 0.009″, and tighten the locking ring down barely finger tight, so that after you tighten the locking ring set screw you can still remove the die from the press.
What do the dies do? The Form die makes the first reduction in the neck diameter, and the Trim die makes the second. Both may also move the shoulder back some. The trim die can also be used to “trim the cases to length” by inserting the case and using a file to shorten the case to length. Supposedly you don’t file the die as well as the case. The Full Length die makes the final reduction in the neck size, sets the shoulder back into the correct position, and forms the body to the correct shape. In this particular case of first forming, the FL die does little other than setting the shoulder back to its final position and reduces the size of the neck.
Then, either lube the cases with Imperial Die Wax if you are going immediately into production (just a wee bit of wax on your fingers, no more than just tapping the wax in the little can with your finger), or if you are going to go into a major production, use Lee wax from a tube (this is a repackaged deep draw lubricant that dries overnight, which you can put a touch of inside the mouth of the cartridge case to lube the expanding button on the FL die). The Lee lube dries over night and is super slick, but does not interact with the powder when you charge the case.
The progression from .22 Hornet to .17AH.
With the dies you have just adjusted and the brass you have lubed, start with the Form die. You may have had to put the extended shell holder in the press, depending on which manufacturer’s die you are using. Run 2 or 3 cases through the form die. Check to make sure they aren’t too deformed, as too much or not enough wax can cause a problem (only with Imperial Die wax, but not with the Lee lube unless you don’t let it dry).
Put the Trim die into the press and repeat the process (or just rotate the shell holder in the turret press to the next position).
And last, run the brass through the FL die.
Carefully chamber the resulting piece of brass. The bolt may not close. If it does not, turn the FL die in as little as 1/32 of a turn and run the piece of brass through the die again. Continue this until the test piece of brass allows the bolt to close with just a touch of resistance. Note here that this means just a touch more resistance than if closed with no brass in the chamber. When you find that sweet spot put a piece of cellophane tape on the base of the test piece of brass and the bolt should close with effort , or maybe not close at all (DON’T FORCE IT!) as the cellophane tape has a thickness of about 2 thousandths.
But suppose the bolt closed easily with the set of adjustments it was set with at first. Go back and turn all of the dies out another 1/8 turn and repeat the process with a second set of brass. This should certainly be long enough that you should be able to get the dies set to that sweet spot that they are allowing the bolt to close with just a touch or resistance more than with an empty chamber.
Last scenario is if you have screwed all of the dies down tight against the case holder and they won’t let the bolt close. You will need to take a shell holder to your favorite smith and have him remove about 10 thou from the base of the dies or the top of the shell holder.
Note also here that you must always use the same shell holder. They vary as much as 10 thousandths from manufacturer to manufacturer and almost as much within individual manufacturers.
Last step is to trim the case length, chamfer the outside of the mouth and bevel the inside.
At this point, make a run of 5 cases, load them with a STARTING load from a reliable source, seat the bullet just off of the lands and shoot a test target. If you’ve done everything right and have the headspace adjusted properly, the cases should form perfectly.
The starting load may not be hot enough, however, and if the outside of the case is “smoked” and/or the angles aren’t fairly sharp, you need to increase your initial loads. AA-1680 is dense enough that the form load and the hunting load may be the same. Regardless, in my guns the forming load is as accurate as the full load. If this is the case for your gun (it is for mine and that of several of the 17AH guys hereabouts) there is no reason not to just load the first batch of unfired cases and take them hunting. Click here for 17 Ackley Hornet Data: 17 Ackley Hornet Loads
Be safe! Shoot carefully! Have fun!
Alex Clarke
6/24/15