BruceB
06-08-2006, 03:27 PM
When I ordered the NEI mould for my .404, the catalog specified ".000 to .003 over stated size". The stated size for the 400 RN was .421", and that is almost exactly the diameter of the bullets from it, cast hot, fast, and water-dropped in straight wheelweights. I'm sizing them at .419" for my .404's .4185" groove diameter.
Musing during the casting of about 500 311466s yesterday, it occurred to me that since I'm already sizing them at .419", how much more difficult could it be to size them at .417", and then try 'em in the .416??? Answer: not very difficult at all. I sized some already-sized-and-lubed .419s in my .417 die, and loaded a dozen rounds for a trial run this morning.
At fifty yards from the 'mobile benchrest', I fired a six-round group which is just under an inch...those big raggedy holes are sometimes tough to measure accurately. The velocity of this 400-grain RN with 47.5 grains of 5744 and a dacron tuft averaged 1901 fps, extreme spread was 20 fps, and the standard deviation a paltry 6 fps. The bore remains nice and clean. This is quite an energetic load from the bench, and the whole field of view turns white when the rifle goes off...whether it's muzzle blast or detaching retinas, I'm not sure.
Sizing the bullet down this much causes it to lengthen a bit, about .020", and of course that's why I used the lubed bullets, to prevent the grooves from closing up during sizing. Apparently it doesn't hurt the accuracy, though.
Musing during the casting of about 500 311466s yesterday, it occurred to me that since I'm already sizing them at .419", how much more difficult could it be to size them at .417", and then try 'em in the .416??? Answer: not very difficult at all. I sized some already-sized-and-lubed .419s in my .417 die, and loaded a dozen rounds for a trial run this morning.
At fifty yards from the 'mobile benchrest', I fired a six-round group which is just under an inch...those big raggedy holes are sometimes tough to measure accurately. The velocity of this 400-grain RN with 47.5 grains of 5744 and a dacron tuft averaged 1901 fps, extreme spread was 20 fps, and the standard deviation a paltry 6 fps. The bore remains nice and clean. This is quite an energetic load from the bench, and the whole field of view turns white when the rifle goes off...whether it's muzzle blast or detaching retinas, I'm not sure.
Sizing the bullet down this much causes it to lengthen a bit, about .020", and of course that's why I used the lubed bullets, to prevent the grooves from closing up during sizing. Apparently it doesn't hurt the accuracy, though.