RCBS 165 Sil - WC872 - Powder Coated in 308 Winchester

[MUSTANG]

Shot 10 rounds of Duplexed WC872 Powder today. in 308 Winchester - Boolit was RCBS 165 Sil, completely coated with Eastwood Green Powder Coat. Baked for 45 minutes - then water quenched. The base was sized to .310 with an aluminum gas check applied after PC process. The nose only was sized in a Lee .301 Sizer die. Powder was 40 Grains of WC872 (this is a 20mm Vulcan Surplus Powder). A 5 Grain "Kicker" of 700X powder was used as a kicker on top of the Flash hole to get a 100% burn of the WC872 Powder.

Rifle: Remington 700 ADL Varmint .308
Barrel Twist: 1 in 12
Wind: 5 Mph left to right.
Temp: 80 degrees F.
Boolit: 308 RCBS 165 Silhouette
Ballistic Coefficient: 0.286
Brinnel Hardness: 20
Bullet sized: .310
Nose Sized: .301
Alloy: 96% Lead, 3% Antimony, 1% Tin
Bullet Powder Coated: Eastwood Green
Gas Check: Ameri-max Aluminum 0.14”
Powder: 40 Grains WC-872
DUPLEX: 5 Grains 700X powder
Primer: Remington Large Rifle
Case: Mixed military and commercial Brass
OAL: 2.80 inches
Distance: 100 Yards.
5 Shot Group Size: 4.051

Click image for larger version.

303574


Average Velocity for 10 Rounds: 2112 Feet Per Second


Comment - The RCBS 30-165-Sil tends to be a fairly accurate boolit for me in a variety of .308's. The group size was just shy of twice the size for previous WC-872 Duplex load using the RCBS 30-200-Sil boolit last week in .308. This test string did contain a larger WC-872 powder charge compared to last weeks with the heavier RCBS 200 Sil boolit.

See link at: https://castboolits.gunloads.com/showthread.php?446326-RCBS-200-Sil-WC872-Powder-Coated-in-308-Winchester&highlight=

[Loudenboomer]

Interesting. Thanks for sharing the info Mustang. I've done similar testing with WC860 in the 308.
I used the Lyman 311284 bullet checked and sized .311. I got best results with a dacron over powder tuft. (enough to keep powder in place)
I tested kickers up to 9 grains all with IMR 4198 and a fed 210 LRP My results were similar to yours.
I was a little surprised how well The NO kicker load did. Just a little compression on the powder with a Fed 215 LR magnum primer.

[lotech]

This has been a pretty accurate bullet design for me in a couple of .308s. I size and lube conventionally and use a .311" size die. I load ww bullets (about 180 grs.) to around 1750 fps with 5744 powder. I've tried Reloder 7 but can't get it to shoot as well as 5744. Using linotype, I've seen very good accuracy up to over 1900 fps. I prefer a heavier bullet and have tried the 30-180 SP, but it's never been quite as accurate for me as the 165.