300 rum accuracy?

I was going to buy an spa long range in 300 win mag but thinking of getting the rum instead. Huh maybe I should just talk my buddy into selling me his.
 
eppie

My use would be elk and larger. The rum is too big for deer but now that I think of it it would save me some time. I would not have to grind any of the meat for a burger!!
 
Belted cases are notorious for accuracy problems? Really??? Guess we should all git rid of our belted case rifles.

Just like any other cartridge, accuracy is dependent on a lot of factors. Usually the most important factor is the shooter.
 
Belted cases are notorious for accuracy problems? Really???
Yes. Competant competitors using them for long range matches in the late 1950's using Sierra's then new 180 to 200 grain FMJBT match bullets learned that new cases gave the best accuracy. 'Twas the only way one could get 1 MOA many-shot test groups at 1000 yards. No fired case sizing method (full length or any type of neck sizing) produced cases that shot as accurate as new ones. After Sierra made hollow point boattail match bullets the were more accurate, this issue became more noticeable.

Someone finally noticed the tiny ridge in front of the belt that, if not sized down to the same diameter as the body in front of it, it would interfere with the chamber at that point. Such irregularities caused accuracy problems. After making a "body" sizing die by cutting off the bottom and top of a conventional full length sizing die then using that to finish size a case all the way to its belt could reloaded ammo equal the accuracy of new cases. Finally, long range accuracy with shoulder fired rifles was down in the 1/2 MOA range. And it got hard to break ties when ammo shot so many identical scores. This was the main reason the NRA's long range target had its scoring ring diameters made smaller in the early 1970's

Nowadays, there's a collet die that does the same thing only better. www.larrywillis.com

Guess we should all git rid of our belted case rifles.
Good idea if you like to reload your fired cases and want to get and are capable of no worse than 5/8 MOA accuracy through 1000 yards; you'll need no worse than about 1/4 MOA at 100 yards to do that. Else make your own body die or get one from Larry Willis. Otherwise, deal with the accuracy you and your hardware produce.

Just like any other cartridge, accuracy is dependent on a lot of factors. Usually the most important factor is the shooter.
Humans play no part in the accuracy a rifle and its ammo has. Proof's easily seen when rifles and their ammo are tested in accuracy cradles or machine rests. Note that the accuracy of rifles and their ammo's all relative to where the rifle's aimed when fired. Rifles and their ammo have no idea whatsoever how they're being aimed and held doing so. A good marksman can sight in a super accurate rifle and ammo at 200 yards firing only 1 shot fired from standing without a sling and not even having the rifle pointed dead center on the target when it goes off.
 
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Strange.........A lot of F class has been won by 300WM. Explanation please.
I've already explained how that can happen. For specific details, ask the folks who won those F class matches using that cartridge.

A recent 1000 yard benchrest record was set with brand spanking new .300 Weatherby Magnum cases. And the 1000-yard prone record set in 1996 was shot with a .300 Win. Mag. with cases sized as I mentioned earlier with 19 of the 20 shots in the 10-inch inner ring. One shot was about 1 inch out.
 
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This is all very interesting. Besides the 300 wsm are there any non belted cartridges that mirror the performance of the 300 win may?
 
Both Remington and Winchester make non-belted rimless bottleneck rounds in 30 caliber that'll do just fine. Pick one of the larger ones.

Interesting part about both is a gunsmith back in 1913 chambered rifles for the .30 Newton (cartridge designer's name) and about the same size as belted magnums but without the belt. It took 8 decades for that type of cartridge to become popular. It's the same size case as a .338 Win. but in 30 caliber. Effectively the same as the .30-.338 which was favored over the .300 Win. Mag. for matches as it was a bit easier to get best accuracy from.
 
The 300 Short Action Ultra Mag and 300 Ruger Compact Magnum are beltless, as are the proprietary Lazzeroni magnums and short magnums.

But I wouldn't fear the belt. If you really need to resize the body down that far collet resizing dies are available.

Jimro
 
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