The Workhorse Load - Mattern's "200 yard Target"
My favorite load is the most accurate. Mattern's so-called "200 yard target load." I expect 10 shot groups at 200 yards, firing prone rapid with sling to average 4-5". I shoot high Sharpshooter, low Expert scores across the course with an issue 03A3 or M1917, shooting in a cloth coat, using may cast bullet loads. The power of this load approximates the 32-40, inadequate for deer by today's standards. Mattern's "200 yard target load" is easy to assemble. Because it is a mild load, soft scrap alloys usually give better accuracy than harder ones, such as linotype. Local military collector-shooters have standardized on 16 grains of #2400 as the "universal" prescription. It gives around 1500 f.p.s. with a 150-180 grain cast bullet in almost any military caliber. We use 16 grains of #2400 as our reference standard, just as high power competitors use 168 Sierra Match Kings and 4895.
The only common military rifle cartridge in which 16 grains of #2400 provides a maximum load, and which must not be exceeded, is in the tiny 7.63x39mm case. Most SKS rifles will function reliably with charges of #2400 as light as 14 grains with the Lee 12-155-2R at around 1500 f.p.s. I designed this bullet especially for the 7.62x39, but it works very well as a light bullet in any .30 or .303 caliber rifle.
Sixteen Grains of #2400 is the Universal Load
The same 16 grain charge of #2400 is universal for all calibers as a starting load. It is mild and accurate in any larger military case from a 30-40 Krag or .303 British up through a 30-06 or 7.9x57, with standard weight bullets of suitable diameter for the caliber. This is my recommendation for anybody trying cast bullets loads for the first time in a military rifle without prior load development. I say this because #2400 is not "position sensitive", requires no fiber fillers to ensure uniform ignition, and actually groups better when you stripper-clip load the rifle and bang them off, rather than tipping the muzzle up to position the powder charge.
Similar ballistics can be obtained with other powders in any case from 7.62x39 to 30-06 size. If you don't have Hercules #2400, you can freely substitute 17 grains of IMR or H4227, 18 grains of 4198, 21 grains of Reloder 7, 24 grains of IMR 3031, or 25.5 grains of 4895 for comparable results. However, these other powders may give some vertical stringing in cases larger than the 7.62x39 unless the charge is positioned against the primer by tipping the muzzle up before firing. Hercules #2400 does not require this precaution. Don't ask me why. Hercules #2400 usually gives tight clusters only within a narrow range of charge weights within a grain or so, and the "universal" 16 grain load is almost always the best. Believe me, we have spent a lot of time trying to improve on
this, and you can take our word for it.
The beauty of the "200 yard target load" at about 1500 f.p.s. is that it can be assembled from bullets cast from the cheapest, inexpensive scrap alloy, and fired all day without having to clean the bore. It always works. Leading is never a problem. Once a uniform bore condition is established, the rifle behaves like a .22 match rifle, perhaps needing a warming shot or two if it has cooled, but otherwise being remarkably consistent.
The only thing I do after a day's shooting with this load is to swab the bore with a couple of wet patches of GI bore cleaner or Hoppe's, and let it soak until the next match. I then follow with three dry patches prior to firing. It takes only about three foulers to get the 03A3 to settle into tight little clusters again.
