You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Low-power 9x19 data
- Thread starter Zak Smith
- Start date
VV-N320 data
11-9-2002, 45F, 5000'
Control .22LR/Browning: 1046
Following shot in CZ75BSA
VV-N320, West-Coast plated round-nose (PRN) 115gr, 1.120" and Hornady XTP 115gr to 1.100"
I'm not sure why the two lightest PRN loads varied so much. It may be because the seating on those was particularly inconsistent. In the Hornady dies, I was having a hard time getting them to seat straight. In the SDB, they seat fine.
The other theory is that the powder volume isn't a high enough fraction of the case volume in those loads. I could try seating them deeper and see if it gets better.
My next low-power batch will be 3.4gr VV-N320, 115gr PRN, 1.120", which should give around 872fps, or 100 PF. In addition, I'll do a batch of 3.4gr seated to 1.100" to see if the stddev goes down.
11-9-2002, 45F, 5000'
Control .22LR/Browning: 1046
Following shot in CZ75BSA
VV-N320, West-Coast plated round-nose (PRN) 115gr, 1.120" and Hornady XTP 115gr to 1.100"
Code:
PRN XTP
3.5- 893 (47) 924 (55)
3.8- 946 (83) 1017 (31)
4.1- 1010 (14) 1107 (21)
4.4- 1122 (16) 1152 (12)
4.7- 1167 (16) 1207 (16)
5.0- 1212 ( 6) 1248 (15)
5.3- 1257 (17) 1302 ( 3)I'm not sure why the two lightest PRN loads varied so much. It may be because the seating on those was particularly inconsistent. In the Hornady dies, I was having a hard time getting them to seat straight. In the SDB, they seat fine.
The other theory is that the powder volume isn't a high enough fraction of the case volume in those loads. I could try seating them deeper and see if it gets better.
My next low-power batch will be 3.4gr VV-N320, 115gr PRN, 1.120", which should give around 872fps, or 100 PF. In addition, I'll do a batch of 3.4gr seated to 1.100" to see if the stddev goes down.
More data.
Over the last couple months, I've gathered some more data. I wanted to add it to this thread before TFL shuts down.
First a short digression into "normal" power 9x19.
9x19 115gr PRN (West Coast) 1.120" +/- 0.005", 4.7gr VV-N320 WSP: -> 1151fps (17.5) in CZ75B-SA
Same, but XTP, OAL 1.097" -> 1152fps (74)
Okay, back to low-power...
115gr PRN 1.120" 3.4gr VV-N320 -> 917fps (15.5) in CZ
same, but OAL = 1.100" -> 943fps (25)
Same, but 3.2gr VV-N320 -> 894fps (19.6)
Same, but WSPM -> 924fps (22.1)
Back to WSP, 3.0gr VV-N320 -> 829.6fps (35.7) in CZ (a bit too slow, fail to lock slide back)
Same, but 3.0gr Bullseye -> 900fps (26)
Bullseye has WAY more muzzle flash than VV-N320, but it operates better in this power regime. The VV-N320 starts to "drop off" non-linearly below 3.2 - 3.0gr.
In summary, I've settled on the following low-power loads:
#1: 115gr PRN (West Coast), 1.100" +/- 0.005", various brass, WSP, 3.2gr VV-N320
#2: Same, but 3.1gr Bullseye.
Both are loaded with my SDB and have the normal crimp, and both operate flawlessly in both my CZ-75B-SA and my GF's CZ-75 Compact (stock recoil springs).
-z
Over the last couple months, I've gathered some more data. I wanted to add it to this thread before TFL shuts down.
First a short digression into "normal" power 9x19.
9x19 115gr PRN (West Coast) 1.120" +/- 0.005", 4.7gr VV-N320 WSP: -> 1151fps (17.5) in CZ75B-SA
Same, but XTP, OAL 1.097" -> 1152fps (74)
Okay, back to low-power...
115gr PRN 1.120" 3.4gr VV-N320 -> 917fps (15.5) in CZ
same, but OAL = 1.100" -> 943fps (25)
Same, but 3.2gr VV-N320 -> 894fps (19.6)
Same, but WSPM -> 924fps (22.1)
Back to WSP, 3.0gr VV-N320 -> 829.6fps (35.7) in CZ (a bit too slow, fail to lock slide back)
Same, but 3.0gr Bullseye -> 900fps (26)
Bullseye has WAY more muzzle flash than VV-N320, but it operates better in this power regime. The VV-N320 starts to "drop off" non-linearly below 3.2 - 3.0gr.
In summary, I've settled on the following low-power loads:
#1: 115gr PRN (West Coast), 1.100" +/- 0.005", various brass, WSP, 3.2gr VV-N320
#2: Same, but 3.1gr Bullseye.
Both are loaded with my SDB and have the normal crimp, and both operate flawlessly in both my CZ-75B-SA and my GF's CZ-75 Compact (stock recoil springs).
-z