ericthered
UZI Talk Supporter
- Joined
- Jun 19, 2020
- Messages
- 320
I made some gun cotton to burn, but then was thinking about if it was a practical propellant in place of powder. I loaded some in 9mm and ran it throug the Uzi. I figured the uzi was the best bet as it can handle the +p++ loads some folks use, and I had no idea what actual pressures I would be running. Nitro cellulose burns quite fast, so figured it wouldnt be to far off for a pistol powder.
My first tests I did not chronograph. They were 6 grains of cotton with a 90 grain hornady xtp bullet. Judging from the sound (all tests were done using a suppressor) my pressures were all over the place (mainly on the subsonic side) and it wasnt ejecting very far (i was loading singles). I was tamping the cotton in with a allen wrench as even as I couldand I figured the bullet was not completely compressing the charge. Hence the erratic "sound".
Felling better about still having a face and not blowing it off, I loaded some more and chronied them. I loaded the 90gr with 7 gr of cotton this time hoping to get a more consistent burn. I loaded some 115gr fmj with 6 grains to see how that goes. Here are my results (they come out of the chrony in .pdf).
Forgot to mention. I did load all 5 of each string in a mag to check reliability. The 90 gr with 7 gr of cotton cycled quite well in the Uzi. The 115gr with 6 gr did not cycle well at all. It was all failure to feed.
My first tests I did not chronograph. They were 6 grains of cotton with a 90 grain hornady xtp bullet. Judging from the sound (all tests were done using a suppressor) my pressures were all over the place (mainly on the subsonic side) and it wasnt ejecting very far (i was loading singles). I was tamping the cotton in with a allen wrench as even as I couldand I figured the bullet was not completely compressing the charge. Hence the erratic "sound".
Felling better about still having a face and not blowing it off, I loaded some more and chronied them. I loaded the 90gr with 7 gr of cotton this time hoping to get a more consistent burn. I loaded some 115gr fmj with 6 grains to see how that goes. Here are my results (they come out of the chrony in .pdf).
Forgot to mention. I did load all 5 of each string in a mag to check reliability. The 90 gr with 7 gr of cotton cycled quite well in the Uzi. The 115gr with 6 gr did not cycle well at all. It was all failure to feed.