Neck reamed some more cases and doing some load development. Tweaked on barrel / mag interface to feed a larger range of bullets. Definitely finding the sweet spot where these blow back like to run. Major issue is going to be brass production. Making a trip back to the shop so will get some TCM sent up there and see if trimming and re-sizing is an option as I still have a very high attrition rate on brass production. Annealing helped but need a more consistent method. If I could find a way to stretch out the necks of the 30 Mauser, might be an option. Get the right length and thin them out at the same time.
there is a guy that sells cutting jigs for .223 to 22TCM case lengths using a Harbor Freight mini-chop saw. I use one of his .223 to 7.62X25 Tok jigs and it does make life a lot simpler. With you being a machinist you could probably make something similar. I do the 7.62X25 cases from .223 cases because the .223 brass is easy to find at the range and it can take a lot more pressure which equals to lasting a real long time. My biggest problem with creating 22 Read Express cases was the creating the smaller diameter necks and I wonder if just using the FL die that Ammo Warehouse sells would be up to creating the neck or if the cases needed to partially run through something like the 7.62 Tok die to reduce the big case mouth of the fresh cut .223 brass first. Creating the .17 Reed Express required a little help from Houdini's ghost to get the neck resized. When I got that one right I did a bunch of the 17 RE brass so I wouldn't have to do it twice.
Got chamber and sizing die reamers done and modified a 22RE die to 22 Uzi specs. Hardened it back up and polishing it out. Going after the barrel this morning and then see how fire forming and re-sizing look.
Got the bug to fire form (have to get the tcm done also) so I whipped up a quick bench that I can mount on a vise. If it works, I'll mount it inside the trailer / garage / workshop.
Tried this yesterday but no real way to measure powder..... but I tried anyway....
Started w/4gr of Bullseye and threw the case about 30' so backed it off to 3gr. Was using my cast 37gr boolits and figured I would try a TCM 40gr JFN. With the un-turned necks, I didn't know what to think, but prepped brass came out at .245 necks and my reamer is set for .253. So I shoved one in and dang if it didn't chamber!
Here is the result:
L - R: Prepped case, 4gr ch w/lead boolit, 3gr ch w/JFN, Original 22 Uzi (short 22 RE)
You can see we blew the shoulder and body out using the JFN and 3 gr charge more than the 4gr charge. Both cases re-chambered so the 3rd case is close to chamber size. After I do a few more of these I'll see what our new sizing die will do to them. Prepped case is .368 at shoulder, 22 RE is .365, and the 22x9 is .380. The necks are in tact and we are one step closer.
Did some measuring and loaded up some more 3 gr fire form loads.
That's a TCM case on the left. You can see the difference between my original 22 uzi and the formed 22x9 cases which have the funky neck geometry.
Yep, they fit the uzi mags just fine....
Here's a bunch of fired cases from the 22x9 blow back barrel set up. I used a few different buffers to try and slow things down as much as possible to keep the shoulders from being "recoiled" forward. I used bro's formed cases and ran them through the 22x9 seating die. I chamfered the necks in and out and lost a couple because of the tight fit when seating the bullets.
I put formed, un-fired cases on the ends for comparison so you can see the difference as the shoulders were blown forward from left to right. Now to see what the sizing die will do....
L-R: Formed brass, fired w/max blown shoulder, sized case
Everything worked but not 100% happy with my sizing die. My neck and button are a bit too big. I turned the button down so I don't enlarge the necks when sizing, but the od is a bit larger than I wanted. The plus side of that is the formed cases chambered and fired without neck work. Now I'll run a few of the formed cases through the sizer to expand the necks from .243 to .250 before seating bullets to help that out. Also going to anneal a few necks as they seem a bit brittle. Another step closer so now I'll review my measurements and make sure my case geometry is where I want it. I'll keep forming and reloading to see how the brass holds up and once that is done I'll get a real reamer and die sets. One step closer.
Had a great range day yesterday at Holton Gun Club. Fire formed a bunch of 22x9 cases. Just stood at the bench and picked out clumps of grass in the sand back stop at 220 yds. Loads were a bit light and had to swap out buffers to help out. Not bad tho for an old blind guy off hand w/no sights. Wish there had been some big bore rams back there, they wouldn't have had a chance!
Also had to sight in a 50 for a guy, yea, its a tough job, but....
I don't know what got more attention, the 50 concussion or hitting stuff with the 22 at 200+ yds Great day at the range!