Updated Factory Short Magnums/Ultramags

Preferred magnum/ultramag bottle neck cartridge Hunting Rifle setup


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The WSM series of cartridges was one of the last to use the old single-taper chamber design (as opposed to having a section of snug freebore to assure bullet alignment prior to rifling engagement). Remington had switched to using freebore by the early 1960's and the RSAUM series has it. The 6.8 Western follows this design as well. Hornady engineers have stated that a section of .1" or more of snug freebore helps with average accuracy and makes the rifle less picky as to which loads it likes.

I have wondered if people have found SAAMI-chambered WSM's (and Winchester Magnums, in general) to be noticeably more finicky than the Remington and Hornady magnums and short-magnums?
Thanks
 
trying to learn here, what would the difference in performance be in a 24-26" 300 wsm versus a 20" 300 prc with the same bullet weight?
The 300 PRC has a higher volume case, a faster standard twist, and greater head height (how far the bullet protrudes from the case). This means it can shoot heavier bullets and bullets with longer ogives (and consequently higher BC's). This would make a difference at long range. The 300 WSM is limited by the short action (2.86") and slower standard twist rate.*

If you want a direct comparison using the same bullets:
I looked up data for the 212 ELD-X for both on Hornady's site.** When both have 24" barrels, the 300 PRC has a max velocity of 2898fps and the 300 WSM is 108 fps slower. With that particular bullet, is likely that a 300 PRC with a 20" barrel would be virtually the same velocity as the 300 WSM with a 24" barrel. The 300 PRC would use 81.1 grains of Staball HD and the WSM would use 61.7 grains of Hybrid 100V.

With a 180 grain Nosler E-Tip, the 300 PRC's velocity is 3190 fps and the 300 WSM is 171 fps slower when both use a 24" barrel. This time, a 20" 300 PRC might have a bit of a speed advantage.


* It should be noted that the 300 WSM can be used in a longer action and a custom barrel with custom chamber fitted. That, of course will usually cost more than a factory 300 PRC rifle. Handloaded ammo would be needed to take advantage of the custom rifle. This setup would likely increase the WSM's velocity and possibly put it ahead of the PRC in short barrels.

** The 212 gr ELD-X would have a long jump to the lands for the 300 WSM. It might have accuracy problems. The heaviest 300 WSM factory ammo I could find was 200 grains.
 
Have these 200g eldx Precision hunter been out a while? Not sure how I missed that. Any body running these out of a xbolt 23 inch 10 twist?? Doesn't look like they have any recommended twist rate posted on their website for this for some reason

I assume since they're making these now they won't be redoing 300 short magnum anytime soon??



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It almost look like hornady's 300 WSM ELDX is different shape than their 300 PRC ELDX. Do they make their bullets in different shapes even if they have the same name like ELDX? If so, that is confusing as chit.
 
Have these 200g eldx Precision hunter been out a while? Not sure how I missed that. Any body running these out of a xbolt 23 inch 10 twist?? Doesn't look like they have any recommended twist rate posted on their website for this for some reason

I assume since they're making these now they won't be redoing 300 short magnum anytime soon??



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Recommend twist is 10. It's the same bullet just stuffed way in the case so it fits a SA. They don't make the in different shapes (lol). A 200 ELDX in a PRC is the same as a WSM. I had pointed out that ammo also earlier in the thread.

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I'll let you know soon hopefully if it's doable.

300SAUM Improved. It's throated for 185 Juggernauts, but I'm also going to try 200.20x bullets. The 185 Juggs are seated at 2.950 and above the n/s junction. Hawkins hunter mags allow 2.980" so the 200.20x should still be able to be seated optimally.

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That 300RSAUMI looks like it would be about perfect for me. Yal going to make me build another gun and start reloading again. Would 300RSAUMI work in the greatest action and bottom metal ever made?? If not what the newest heaviest fastest 30cal wildcat that would work best in this with 20-22 inch barrel? I like them short AI magazines with the peephole for round counts...

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