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22 UZ
Jul 12, 2020 10:43:54 GMT -5
Post by HMC710 on Jul 12, 2020 10:43:54 GMT -5
cutting some more of my formed brass down to drop them to .850". Unfortunately I'm getting high attrition with cracks at the shoulder.....
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22 UZ
Jul 12, 2020 12:37:44 GMT -5
Post by HMC710 on Jul 12, 2020 12:37:44 GMT -5
more annealing....
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22 UZ
Jul 12, 2020 16:29:04 GMT -5
Post by squirrelslayer on Jul 12, 2020 16:29:04 GMT -5
I have yet to try annealing. On my 22 Adder I push the shoulder back with a 23' shoulder angle (actually my buddies ".223 short" chamber reamer I made a die with. I push the shoulder to about 1" datum point of the shoulder. I then use my 30' shoulder FL sizing die to the final case dimensions. I have yet to have a neck/should split failure yet after doing it in those steps. I do however have to inside neck ream cases as they are just way to thick down there. I made a jig with the chamber reamer that worked out pretty well. Here is my order of operations for neck lob and inside ream (necks aren't that long since I'm using the remaining stock of my .223 short cases I had formed awhile back before we re-designed the cartridge into the 22 Mamba) I did get about a 6% failure rate of split necks on the first firing. On the third firing now and haven't lost a case(aside from 3 over pressure cases) which is pretty common on my 22 Mamba wildcat. They either fails first firing or works fine for normal brass life ~4-7 firings. I'm using Accurate #9 now and it really has cleaned up the ES/SD and lower pressure signs. 8.6gr netted me 2200 ft/sec on the nose with the 34gr dogtown The report is way boomier love it! (this is with a 5.2" glock barrel and 11gr H2o case capacity) I am getting one weird thing however. i'm getting more case expansion between the middle of the case and where the shoulder starts than the web which is causing sticking cases. i'm assuming this is due to the web being strong enough to prevent expansion. problem is cases are snug to extract but it's weird I can push the case back into the barrel and it will spin when seated all the way. you pull it back and it sticks. Their is minimal case taper since this wasn't really designed for such a short case so I just got back inside from polishing a touch more taper into the chamber with some 800gr paper wrapped around a dowel, checking with a sharpie and a fired case for contact. Then I used the fired case with some rouge on it to final polish it so it just barely slides in with minimal resistance.
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22 UZ
Jul 12, 2020 19:26:26 GMT -5
Post by HMC710 on Jul 12, 2020 19:26:26 GMT -5
Might have got a bit aggressive on the annealing, but case attrition when from 50% to 0%. Even formed some new cases in 2 passes..... Playing with powder charges....
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22 UZ
Jul 12, 2020 19:34:03 GMT -5
Post by HMC710 on Jul 12, 2020 19:34:03 GMT -5
Nice work squirrel! Jigs are very handy. I running #9 right now in the Uzi. My chrono crapped out this spring so I'm just testing loads by "feel" and signs of pressure. There is no way the AR blow back can handle true full charges that a locked breach can. When I did my glock barrel way back when, I could get it to fire and unlock and that was about it.
Whats your mamba OAL with the dogtowns? I'm at 1.15"
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22 UZ
Jul 12, 2020 19:39:26 GMT -5
Post by squirrelslayer on Jul 12, 2020 19:39:26 GMT -5
The 22 Adder i'm seating 34gr dogtown at 1.16 (my case is .010" longer) so roughly the same.
I may spin up a DI barrel and see how it feeds from MEAN endomags.
The 22 Mamba is a 1.125" case and I have yet to try the 34 dogtown in it yet. I've been shooting the 40gr varmageddon tiped in it ~1.6"
I haven't tried cycling yet. plan to try it soon. I have 13, 12 and 9lb springs to test with. Time will tell
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22 UZ
Jul 12, 2020 21:45:00 GMT -5
Post by HMC710 on Jul 12, 2020 21:45:00 GMT -5
Lots done on the Uzi today. Got 2nd barrel adj for the new case lengths and playing with a few adjustments. This barrel is a lot faster twist so I'll load up some of our SS109 sub loads....
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22 UZ
Jul 26, 2020 21:43:57 GMT -5
Post by HMC710 on Jul 26, 2020 21:43:57 GMT -5
Swapped out powders going from slower to faster and have a sweet little load using Universal. Going to swap that out with AA#5 next test. Got 3 test barrels, all with a bit different chamber. Need to get settled in on a final final.... Next step is to make up some more brass. some of my shoulders are pushed back a bit too far so will have to see if I can make up a GO round to get some solid measurements off of.
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22 UZ
Jul 29, 2020 21:25:09 GMT -5
Post by HMC710 on Jul 29, 2020 21:25:09 GMT -5
Now to make more brass.... made a couple swag dies to try and find that sweet spot....
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22 UZ
Aug 1, 2020 18:39:55 GMT -5
Post by HMC710 on Aug 1, 2020 18:39:55 GMT -5
New dies helped so might need one more intermediate step.... also going to change powders tonight....
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22 UZ
Aug 3, 2020 21:42:13 GMT -5
Post by HMC710 on Aug 3, 2020 21:42:13 GMT -5
we'll try this again.... After investing in reamers and dies at .905" length, I decided to cut things down .050" and get some better bullet selections.... Formed up a bunch of cases after getting new form dies sorted out. My 30 Luger size die didn't knock the shoulders back far enough so that was the first die to make. Couldn't effectively go right to the 22 cal, so we did a 256 second step die. Then as a test, did a tighter full length UZ size die. The time consuming part was getting shoulder heights adjusted and matched to the 2 cut down .900" chambers. I also did a tight chamber on a 3rd test barrel. after a couple of days of forming sizing, annealing, forming, loading, we got to a new "standard" The 40gr armscor TCM bullets seated in the cannalure measure 1.15", good for any glock or colt mag. Then we went from trying 3 rounds at a time to 10, bumping up our load of 231 and measuring cases when they came out of the two test barrels. Both barrels would result in pushing the shoulders forward so we worked on the best way to get them back to shape. Resetting them with the 30 cal die first helped out and saved the cases from crushing. Annealing might help as well, but its pretty tough to anneal the neck on a .850" long case with out overheating the base.... 34 gr loads were next
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22 UZ
Aug 3, 2020 21:54:03 GMT -5
Post by HMC710 on Aug 3, 2020 21:54:03 GMT -5
Here are the two test mules... again, this was all into the test chamber so the neighbors didn't get to riled up... The 16" carbine was the #2 barrel with the custom manson reamer and uses a Colt pattern mag adapter. The 8" pistol was cut with one or our modified reamers and sets on a glock mag lower. The 40gr loads each performed about the same with a slight edge going to the 8" pistol for case deformation. Next in line were the 34gr dogtowns A factory TCM on the left. Using the same charge as the 40 gr, there was a noticeable difference between the two barrels. I'm going to do some more testing and see if it is a trend or an a true difference. Either way, with out some chrono testing, (or even having my QL set up here) we don't know where we are velocity wise. I've got a guess, but we need to prove that out. One thing for sure, this is a very fun plinker and much more user friendly than our last set ups. If we can give a performance boost over a std 22lr, and a direct conversion for all you 9mm owners, I'll call that a win.
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22 UZ
Aug 16, 2020 14:02:17 GMT -5
Post by squirrelslayer on Aug 16, 2020 14:02:17 GMT -5
Man haven't been keeping up on this Tim but good work. Are you forming these from 9x23 brass? I thought it was .223 brass at first.
So your at a .900" case now if i'm reading it correctly?
Assuming your doing blowback?
have you measured h2o capacity?
Been to darn hot here for me to do any testing lol.
Keep up the good work!
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22 UZ
Aug 20, 2020 22:05:35 GMT -5
Post by HMC710 on Aug 20, 2020 22:05:35 GMT -5
New case length is .850" which gave us some more flexibility. Parent case is 9x23, but might try 30 luger once we verify some pressures. Yes, this is 100% blow back, that is the whole idea to have a direct conversion for the 9mm uppers.
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22 UZ
Sept 22, 2020 20:21:11 GMT -5
Post by HMC710 on Sept 22, 2020 20:21:11 GMT -5
Walk past all of this on the loading bench and just don't have the time to do anything with it....
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