doubs43
01-07-2010, 01:12 PM
Last week I took delivery of a new Winchester "Limited Series" HiWall rifle chambered in 38-55. The rear barrel sight and the Marble's tang sight were both removed to be replaced with a blank and a Pedersoli USA-431 Creedmoor sight.
Using an RCBS 312BC mold that drops a 320 grain bullet at .379", I cast and sized a quantity of bullets to .377" and lubed them with Carnuba Red in all grooves. I then loaded them into new Starline 2.125" cases using IMR-4759, AA-1680, H-335 and a duplex load of WW-231 & WC-860. COAL measured 2.773"
Long story short, the duplex load was easily the most accurate. It's 2.5 grains of WW-231 and 32.0 grains of WC-860. The primer is a standard LR. The nice thing about WC-860 (and AA-8700 too) is that you can't possibly stuff enough of it in a case to cause high pressures. The only danger is if you drop a double charge of WW-231 so you must be careful not to do that.... just as you would with any fast burning powder. When seated, the bullet compresses the powder and a moderate crimp ensures a consistent, clean burn.
While not a magnum load by any means, neither does the bullet limp along. I haven't put it across a chronograph but it gets downrange quickly.
Yesterday was sunny, 41 degrees and windy on the range. I wanted to get sight settings at 100, 150 and 200 meters. The 200 meter target frame is actually 228 yards as measured by laser rangefinder.
After initial adjustments, my 100 meter 5-shot group measured 1 1/4 inches.
The 150 meter group was 2 5/8 inches. Either I didn't aim carefully enough or the wind had some effect on the bullet..... or both.
At 200 meters, I only fired 5 shots total. The first 2 struck low at 6 o'clock and were exactly 1 inch apart. I elevated the sights and the next 3 were an X and 2 in the 10 ring. Maximum spread was 1 7/8 inches.
I'm very pleased with my first range session using the duplex load. It will do just fine in our local matches.
Using an RCBS 312BC mold that drops a 320 grain bullet at .379", I cast and sized a quantity of bullets to .377" and lubed them with Carnuba Red in all grooves. I then loaded them into new Starline 2.125" cases using IMR-4759, AA-1680, H-335 and a duplex load of WW-231 & WC-860. COAL measured 2.773"
Long story short, the duplex load was easily the most accurate. It's 2.5 grains of WW-231 and 32.0 grains of WC-860. The primer is a standard LR. The nice thing about WC-860 (and AA-8700 too) is that you can't possibly stuff enough of it in a case to cause high pressures. The only danger is if you drop a double charge of WW-231 so you must be careful not to do that.... just as you would with any fast burning powder. When seated, the bullet compresses the powder and a moderate crimp ensures a consistent, clean burn.
While not a magnum load by any means, neither does the bullet limp along. I haven't put it across a chronograph but it gets downrange quickly.
Yesterday was sunny, 41 degrees and windy on the range. I wanted to get sight settings at 100, 150 and 200 meters. The 200 meter target frame is actually 228 yards as measured by laser rangefinder.
After initial adjustments, my 100 meter 5-shot group measured 1 1/4 inches.
The 150 meter group was 2 5/8 inches. Either I didn't aim carefully enough or the wind had some effect on the bullet..... or both.
At 200 meters, I only fired 5 shots total. The first 2 struck low at 6 o'clock and were exactly 1 inch apart. I elevated the sights and the next 3 were an X and 2 in the 10 ring. Maximum spread was 1 7/8 inches.
I'm very pleased with my first range session using the duplex load. It will do just fine in our local matches.