Weatherby magnum cartridge headspacing ... ?
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The .375 H&H Magnum, and its junior counterpart, the .300 H&H Magnum, both headspace off the belt, not off the shoulder. The very slight shoulder on the .375 H&H and the sloping shoulder of the .300 H&H are the features that give those cases the “smooth feeding” quality that proponents of those cartridges love so much. I believe the same could be said of the .416 Remington Magnum. The straight walled .458 Winchester Magnum and the .458 Lott are examples of cases that have no shoulder and also headspace off the belt.
The more familiar magnums, like the .300 Winchester Magnum, 7mm Remington Magnum, .338 Winchester Magnum and .300 Weatherby Magnum all headspace off the cartridge shoulder, and perform best when cases are resized to have that shoulder at the proper dimension. Most every other cartridge that features the H&H style belt will use the shoulder for headspace, and the belt on this style case is non-functional.
The more familiar magnums, like the .300 Winchester Magnum, 7mm Remington Magnum, .338 Winchester Magnum and .300 Weatherby Magnum all headspace off the cartridge shoulder, and perform best when cases are resized to have that shoulder at the proper dimension. Most every other cartridge that features the H&H style belt will use the shoulder for headspace, and the belt on this style case is non-functional.
I agree any belted mag with a decent shoulder SHOULD be headspaced on the shoulder, but i dont think thats factory default. The magnum headspace gauges i have set headspace on the belt, and most of the magnums ive had tend to have kinda long chambers.
My default method for sizing cases for the first firing is to expand the necks a size or two larger, then slowly neck size back till the bolt closes with a little of a crush fit. This almost always leaves the "auxiliary" shoulder a noticeable distance infront of the primary shoulder.
When ive tried this with factory beltless founds ive only had one leave a truly noticeable difference.
My default method for sizing cases for the first firing is to expand the necks a size or two larger, then slowly neck size back till the bolt closes with a little of a crush fit. This almost always leaves the "auxiliary" shoulder a noticeable distance infront of the primary shoulder.
When ive tried this with factory beltless founds ive only had one leave a truly noticeable difference.
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He didn't add a belt, he modified existing belted H&H magnum cases.
My understanding is that belts, while not actually necessary, were retained for marketing purposes, even later wby designs NOT bassed on the H&H cases maintain the belt.
Magnums had belts, Winchester or remington could well have done away with the belts when they designed their original short mags.
Magnums had belts, Winchester or remington could well have done away with the belts when they designed their original short mags.
I dont think they compromise accuracy that much. Perhaps for those guys shooting benchrest, but ive never found a belt to matter one way or the other in terms of MY use able accuracy.
Now the RECOIL suffered from many belted cartridges is another story.
You may want stop looking at it like an engineer (or as a practical, sensible, rational person) it will drive you bonkers lol. There isnt any good reason for a belt on ANY sharp shouldered cartridge.
and for reference the 7mm Remington magnum is my all time favorite cartridge, but again when i load for it i ignore the belt.
Now the RECOIL suffered from many belted cartridges is another story.
You may want stop looking at it like an engineer (or as a practical, sensible, rational person) it will drive you bonkers lol. There isnt any good reason for a belt on ANY sharp shouldered cartridge.
and for reference the 7mm Remington magnum is my all time favorite cartridge, but again when i load for it i ignore the belt.
GooseGestapo
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They only compromise accuracy if the ammo manufacturers or reloaders insist on headspacing on the belt. Just like with headspace on rimmed cartridges. Set dies to headspace to shoulder and forget the belt.
No problemo...
No problemo...
Captcurt
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I have only had one belted Mag and it was a 257 Weatherby in a Vanguard, so I can't speak for all belted rounds. The gun was laser accurate with Weatherby factory ammo. I couldn't tell any difference when I just bumped the shoulder when I reloaded. It still shot where I pointed it. Like the others said, the only reason for a belt would be to headspace a straight wall round or one with a long tapered shoulder.
Clark
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Almost all belted magnums have a SAAMI registered headspace of 0.220" minimum on the belt.
But if I have a lifetime supply of brass and none is over 0.215", then I will headspace the new barrel at 0.215".
I have many thousands of rounds or many brands of 7mmRemMag, 300WinMag, and 338WinMag brass, and I have not found any over 0.215" yet.
I have made a brass checker. In this pic I am measuring a piece of belted magnum brass with a layer of tape to be my 0.215" go gauge.
After the brass has been fired once, one has the option of not pushing the shoulder back very far in resizing, and the reloaded ammo will space on the shoulder.
The brass will last longer in a factory rifle that way.
Those factory rifles are headspaced over 0.220" on the belt, per SAAMI specs.
Factory brass has the shoulder pushed way back, so it is going to headspace on the belt on the first shot.
Yes, you could expand the neck on new factory brass, and with a sizing die form a shoulder that with stand up to the firing pin, and shoot the first shot of factory brass in a factory rifle, and it would be spacing on the shoulder. I don't know anyone who does that for belted mags. People do that for forming 6mmPPC, but it is a lot of trouble.
But if I have a lifetime supply of brass and none is over 0.215", then I will headspace the new barrel at 0.215".
I have many thousands of rounds or many brands of 7mmRemMag, 300WinMag, and 338WinMag brass, and I have not found any over 0.215" yet.
I have made a brass checker. In this pic I am measuring a piece of belted magnum brass with a layer of tape to be my 0.215" go gauge.
After the brass has been fired once, one has the option of not pushing the shoulder back very far in resizing, and the reloaded ammo will space on the shoulder.
The brass will last longer in a factory rifle that way.
Those factory rifles are headspaced over 0.220" on the belt, per SAAMI specs.
Factory brass has the shoulder pushed way back, so it is going to headspace on the belt on the first shot.
Yes, you could expand the neck on new factory brass, and with a sizing die form a shoulder that with stand up to the firing pin, and shoot the first shot of factory brass in a factory rifle, and it would be spacing on the shoulder. I don't know anyone who does that for belted mags. People do that for forming 6mmPPC, but it is a lot of trouble.
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True, but "magnum fever" was rampant during the early years. They were there for bragging rights and we were in awe of anyone who had a belted magnum, especially a Weatherby. Guys spent big bucks to buy a .300 Weatherby and many here in Maine used them on whitetails, usually creating massive wound channels, especially on shoulder and rump shots. The 7mm Remington Mag is probably the most common mag used in Maine. It's probably best used on powerline stands, where 400 yard shots are common.
I remember a firm that made rifles and designed several NON-BELTED magnum cartridges, maybe 20 years ago. I can't remember the name, but also can't find any reference to the cartridges by Google-ing, or looking at the RCBS die list. I think the company name began with "S". He appealed to those who know that belts aren't needed on most magnums. However, I haven't seen any reference to the company, or about the chamberings for several years. So, the shooting fraternity is apparently sold on belted magnums! Must be a bragging thing. (At least nobody has designed a magnum cartridge with suspenders. LOL )
Riomouse911
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Lazzeroni built high-dollar guns like you describe, in their own proprietary maxi-velocity non belted calibers.
GooseGestapo
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Well, back in the day the belted magnums originated, the extra "meat" on the case head was insurance that the case head didn't fail.
By the time WWII came around, metallurgy had progressed to the point that the belt is superfluous.
Ain't progress great!!! But it doesn't make me love my .257wby less. Now if the .25wssm had only been on the larger wssm case.... hmmm
By the time WWII came around, metallurgy had progressed to the point that the belt is superfluous.
Ain't progress great!!! But it doesn't make me love my .257wby less. Now if the .25wssm had only been on the larger wssm case.... hmmm
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