04-01-2012, 11:25 PM
(This post was last modified: 04-01-2012, 11:29 PM by txgunner00.)
FINALLY!!! I have a sub sonic load that cycles my action. Data is below.
20" Satern barrel, AR-15 carrier, 3.0 OZ buffer, gas port diameter .098"
Powder: IMR 8208
Case: IMI 7.62x39, necked down but NOT fire formed.
Primer: Rem 9 1/2
Bullet: 160 Hornady RN
COL: 2.220
Charges: 5 shot strings
14.5 gr, 1187 avg, 36 ES, 13 SD
14.0 gr, 1129 avg, 55 ES, 23 SD
13.5 gr, 1079 avg, 56 ES, 26 SD
All 5 shot strings were fired from a magazine, cycled properly and locked back on the last round. Temperature was 90 deg. (in March :p) so the speed of sound was around 1150 fps. I still intend to do some more testing and fine tuning but these results are encouraging.
Cases were only slightly sooty and I'm hoping magnum LR primers will help with this. Most of the soot blow by could be due to the fact these are not fire formed cases so I'll load some rounds with FF cases to test this theory. I'm using non-fire formed cases specifically for the purposes of increasing load density and fire forming the cases for full power loads.
More to follow as I can get to it...
20" Satern barrel, AR-15 carrier, 3.0 OZ buffer, gas port diameter .098"
Powder: IMR 8208
Case: IMI 7.62x39, necked down but NOT fire formed.
Primer: Rem 9 1/2
Bullet: 160 Hornady RN
COL: 2.220
Charges: 5 shot strings
14.5 gr, 1187 avg, 36 ES, 13 SD
14.0 gr, 1129 avg, 55 ES, 23 SD
13.5 gr, 1079 avg, 56 ES, 26 SD
All 5 shot strings were fired from a magazine, cycled properly and locked back on the last round. Temperature was 90 deg. (in March :p) so the speed of sound was around 1150 fps. I still intend to do some more testing and fine tuning but these results are encouraging.
Cases were only slightly sooty and I'm hoping magnum LR primers will help with this. Most of the soot blow by could be due to the fact these are not fire formed cases so I'll load some rounds with FF cases to test this theory. I'm using non-fire formed cases specifically for the purposes of increasing load density and fire forming the cases for full power loads.
More to follow as I can get to it...