A friend of mine is wanting to build a hot rod 6mm. I saw this load data on reloadersnest and thought it might be a little far fetched. Nosler Ballistic Tip
BulletWeight 70 grs
Powder IMR 7828
PowderWeight 74.5 grs
Primer Winchester LRM
Brass Make Winchester
Barrel Length 28.5 (inches)
Velocity 4400 fps
And the 55 grn Noslers are going 4680 With IMR 7828. It seems to me that the powder would be to slow for that light of a bullet. I know on my 257 Wby mag that slow of powder just makes a bigger fire ball. I was thinking of a 6mm WSM anyone have one. BTW the 240 Incinerator is a 264 Win Mag necked to 6mm. 35 degree shoulder and minimal body taper.
Buffalobob and I both shoot the .240 WBY.
I have mine on a diet of 49.8 of RL 22 with a 105 Berger. 3380 fps in a 28" barrel with exceptional accuracy. I'm not sure of the powder he's using, but he is using the 115 gr Berger with the same crazy accuracy.
Chime in here BB.
I run 51.0 grains of RL 22 with a Fed 210GM primer and the 115 Bergers jammed in a 30 inch barrel. The load is very hot and cannot be used in hot weather. You may not be able to get tht high in powder load. It is just death and destruction on antelope at long range. Of course antelope hunting is not high volume shooting so the barrel seldom is allowed to get hot. The chamber is "minimum SAAMI" so it is tight and the action has been trued.
BB what do you think of a 6mm WSM or SAUM. With a 28"-30" tube, it would seem that you could push a 115 fast for some "death and destruction on antelope at long range". BTW the 257 With a 87grn does wonders on white tail @ 300 on in.
I am not familiar with the 6 WSM or SAUM. I have shot the 240 Wby cartridge for about 20 years and with a 85 grain Speer or Barnes X in a shorter barrel it is a very nice eastern whitetail cartridge. Case capapcity of the 240 Wby is about the same as the 6-284 or 6-06 and caseheads are all the same. Most people opt for the 6-284 because they believe you get better brass. Admittedly Norma brass is soft but it is high quality and I only shoot antelope once a years so it is not a big expense to me to lose a few pieces.
Kirby Allen and some other knowledgeable people expressed reservations about 1-8 twist barrels at high speed because they tend to blow up bullets. They suggested a 1-9 barrel. I have a 1-8 and so far everything is fine but I just shoot that one bullet.
I also have a fondness for the 257 Wby and think it is a nice case.