Went to the range again today. This barrel will not shoot 85gr. partitions. Also will not shoot 95gr. partitions. 60gr. Sierra's, 70 gr. Sierra's both shoot great. 1/2 inch to 3/4 inch groups.
I loaded some 80gr. Winchester flat base soft point bullets and with three different powders they shot into less than 3/4 inch groups.
I loaded some 85gr. Hornady Interbond but dumb me, did not check to make sure they fit into the magazine
. Have to reduce the OAL slightly and go back to check those loads.
Here's my 85/87gr load data for a BHW 18" middy with a 1:10. Between 5&10 rounds were shot of each @ 100yds with a front rest and rear sandbags. Almost all chrono averages are between 65-80 deg. F at 2400' elevation. The data is tab-delimited, so you should be able to copy it out and paste into your favorite spreadsheet.
The Noslers worked fine out of my barrel, tho' I didn't get the grouping at the speed I wanted (~2800fps) The best Nosler grouping was a bit slower at 2599fps with a .182" group of 5. In the end I went with the Sierra Pro-Hunters #1530 @ 85gr. They are *THE* killer round in my barrel, proven by my taking a whitetail buck with them last year.
As with all load data, YMMV (your mileage may vary) so use this info as a reference and not as definitive fact. It worked for me so it might work for you.
Weight Bullet # Type Powder Weight Powder Primer Case OAL Group@100 Velocity FPE
85 NOSLER 16314 PARTITION 23.0 BENCHMARK FED SR PMC 2.258 0.764 2399.3 1086.79
85 NOSLER 16314 PARTITION 23.5 BENCHMARK FED SR PMC 2.258 0.391 2428.3 1113.22
85 NOSLER 16314 PARTITION 25.0 BENCHMARK FED SR PMC 2.258 0.853 2546.7 1224.42
85 NOSLER 16314 PARTITION 25.5 BENCHMARK FED SR PMC 2.258 0.182 2599.7 1275.91
85 NOSLER 16314 PARTITION 26.0 BENCHMARK FED SR PMC 2.258 0.406 2857.7 1541.73
85 NOSLER 16314 PARTITION 26.3 BENCHMARK FED SR PMC 2.258 0.64 2908 1596.48
85 SIERRA 1530 BT-HP 25.0 BENCHMARK FED SR PMC 2.258 0.533 2573 1249.84
85 SIERRA 1530 BT-HP 25.5 BENCHMARK FED SR PMC 2.258 0.26 2643.3 1319.07
85 SIERRA 1530 BT-HP 26.0 BENCHMARK FED SR PMC 2.258 0.316 2786.3 1465.65
85 SIERRA 1530 BT-HP 26.3 BENCHMARK FED SR PMC 2.258 0.241 2817.3 1498.45
87 HORNADY 2442 BTHP 25.0 BENCHMARK FED SR PMC 2.258 0.258 2581 1287.22
87 HORNADY 2442 BTHP 25.5 BENCHMARK FED SR PMC 2.258 0.778 2651.7 1358.70
87 HORNADY 2442 BTHP 26.0 BENCHMARK FED SR PMC 2.258 0.516 2881.3 1604.18
87 HORNADY 2442 BTHP 26.3 BENCHMARK FED SR PMC 2.258 0.199 2874.7 1596.84
Bad Grouping
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Weight Bullet # Type Powder Weight Powder Primer Case OAL Group@100 Velocity FPE
85 SIERRA 1530 BT-HP 23.5 TAC FED SR PMC 2.258 1.04 2472 1153.64
85 SIERRA 1530 BT-HP 24.0 TAC FED SR PMC 2.258 1.63 2474.7 1156.17
Work-up Loads
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Weight Bullet # Type Powder Weight Powder Primer Case OAL Group@100 Velocity FPE
85 SIERRA 1530 BT-HP 23.0 BENCHMARK FED SR PMC 2.258 0.479 2405.3 1092.23
87 HORNADY 2440 Interlock 23.0 BENCHMARK FED SR FC 2.25 na 2353 1069.84
87 HORNADY 2440 Interlock 24.0 BENCHMARK FED SR FC 2.25 na 2471 1179.83
87 HORNADY 2440 Interlock 23.0 BENCHMARK FED SR FC 2.25 na 2353 1069.84
87 HORNADY 2440 Interlock 24.0 BENCHMARK FED SR FC 2.25 na 2471 1179.83
87 HORNADY 2440 Interlock 25.0 BENCHMARK FED SR MI 2.258 1.325 2600 1306.24
87 HORNADY 2440 Interlock 25.7 BENCHMARK FED SR MIX 2.258 1.25 2669 1376.49
87 HORNADY 2440 Interlock 25.9 BENCHMARK FED SR PMC 2.258 poor 2681.4 1389.31