Belted cases and accuracy for long range cartridges

That bulge at the case head, is it really anything to worry about? It would seem to me that with each firing it would only bulge so far and then the chamber would contain it. It seem's to me that by moving it back every time the case would get weak there. I learned to partial size because I was getting a lot of head split's with my 7mm mag. Stopped it pretty well after going to partial sizing. Had two 338 mag's and never had the problem with them. But then with both of them I partial sized. In partial sizing shouldn't the entire case be re-sized some? Even at the head? Even if you leave the case to rub a bit, I would think it would actually be rubbing full length!
 
I think people keep coming back to the 338-378 Weatherby due to it's very slight velocity increase over the 338 LM.

From my understanding the belt was added due to the needs of the British Empire.
Seeing as they ruled India and large swaths of Africa. The belt and long taper helped with headspace, RELIABLE feeding and the ability to extract in the extreme heat when facing dangerous game.

BTW i heard that untill recently the Secret Service was using 7mm Rem Mag for their sniper rifles, and may still be using it.
 
"Thanks for that Paul.

But what about my situation where a fired case still easily chambers in my rifle?? Is what I said above ok to do? Neck size only till the need to resize the whole case presents itself?"

I guess you could do it that way. I quit neck sizing years ago as I saw no benefit. My method is as close to neck sizing while still keeping the main body of the case in line. I had a few instances of the neck being pulled out of alignment using neck sizing dies. I suppose you can try neck sizing till the cases get difficult in chambering. Might work OK as long as the necks stay "straight".
Paul B.
 
I have had rim lock in my 375 H&H Magnum. I was firing 235 grain bullets which are shorter than the magazine. The bottom round slide under the top round. The belt on the top round caught the rim of the bottom round. I was unable to close the bolt because the cases were locked together. I had to lower the rifle, press on the magazine stack, to disengage the bases of the rounds. I had that happen several times.

I have had rim lock in the 7.62 Nagant and the 303 British. I have not had rim lock in my 300 H&H Magnum, don't know why, but overall, I consider the belted magnum case to be something that should have died more than a century ago. I don't want fins, rims, sticking from the side of my cartridge as all they do is catch on stuff.

I do know belted magnum cartridges can be very accurate, I have shot my 300 H&H out to 300 yards and it shoots well for a sporter rifle.


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In so far as the 300 H&H being a target cartridge, Ben Comfort did win the 1000 yard Wimbledon with a 300 H&H and congratulations to him. However he out "V"'d the second place guy, who was shooting a M1903 Springfield service rifle in 30-06. It was not like Ben ran a two minute mile while everyone else ran a 4 minute mile.

The long range National Champions I know, they are shooting 6.5 or currently, 7mm. They don't want the recoil of a big 30 caliber and they want the better ballistics of the sub calibers.
 
I have a 7MM Rem Mag. With hunting ammo, not tricked out target stuff, it'll shoot sub-.25" MOA all day long. Not many target rifles can replicate that.
 
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