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WSM performance comparisons:

I have done comparisons, ballistic and overall characteristic comparisons between the 7mm WSM and the full-length 7mm magnum, and also between the 300 WSM and the 300 Win Mag, and what I have found, after sifting through the somplicated tangle of personal opinion, advertising, and techno-babble, is quite interesting, at least I think so. Starting with the two 7mm magnums, I'll begin with ballistics. The 7mm WSM is said to ballistically outperform the popular 7mm Remington Magnum. It doesn't. with small bullet weights, it breathes down the 7mm Remington Magnum's neck, but with 150 grain bullets, a significant performance gap develops, and becomes very pronounced with bullets in the 160 grain class and up. It's probably apparent to all of us that muzzle velocity has a lot of retail value. It sells. The 7mm WSM, all WSMs, have higher MUZZLE velocity. But, the 7mm Remington Magnum has already caught up at 100 yards, and rapidly overtakes the WSM, and by 300 yards, it's screaming for the win, and the 7mm RM also has a pretty good edge in terms of energy as well. Another thing woth noting is the 7mm WSM sheds energy and velocity quite a bit faster than the 7mm RM. It actually has more bullet drop too, with bullets in the 150 grain class and up. As far as handload potential goes, the 7mm RM exceeds the short 7 mag by a considerable margin, mainly due to its greater case capacity. And now, on to the .300's. The 300 WSM's 150 grain bullet outperormed all bullets compared with the 300 Winchester Magnum (WM), those of the same weight (150 grains). Generally speaking, neither o these two rounds are particularly effecient with light bullets like these, and the 30-06 actually tops both of them with it's 165 grain Hornady-LM at 3015 fps (MV), which holds up tenaciously at increasing range. Moving on to 180 grain bullets, the 300 WM takes over. Although starting velocity is 10-20 fps lower, depending on the exact load, it catches up. Fast. As far as energy goes, most of the 300 WM rounds generate more punch. Less bullet drop too, and as with the 7 RM vs. the 7 WSM, the 300 WM hangs onto its energy longer than the 300 WSM. The 300 WM also has an edge in terms of true handload potential. It can be loaded ''hotter.'' It's also easy to find glowing claims of more efficient powder ignition in these new rounds, something about the primers igniting the powder in a different way than the traditional magnums. Every handloader I've spoken with about this has told me the same thing, a good primer ignites the powder charge in a flash, and that's it. Anyone contesting that should kindly explain how the primer on a WSM round ignites the powder column from the sides. Another thing I have stumbled across in my research has been actual, chronographed velocity versus advertised velocity. According to most chronograph tables I've come across on the Net, the actual velocities for the short mags (not including the 270 WSM, which actually held up remarkably), were below those advertised, whereas the velocities for standard non-magnums and also for standard-length magnums were up to par. The last thing, and one I was particularly fascinated by, was the issue over belts versus shoulders. It's claimed that the cases that headspace off the shoulder are better, but really, there seems to be evidence to the contrary, and very little in favor. It sure doesn't offer any real-world advantage, and all these facts, in conjuntion with the fact that the shorties build up higher pressures, seem to dispel the magic. My sources for this included the recent Petersen's Hunting Annual's ballistic tables, the fine and useful information that can be found at http://www.chuckhawks.com, on the rifle information page, Wayne Van Zwoll's book Accurate Shooting, or some similar name, and last but certainly not least, http://www.midwestmagnum.com, which provided some outstanding techical data on cartridges and primers.

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WSM performance comparisons:

Captain_obvious wrote..."The 7mm WSM, all WSMs, have higher MUZZLE velocity. But, the 7mm Remington Magnum has already caught up at 100 yards, and rapidly overtakes the WSM, and by 300 yards, it's screaming for the win..."
I find this hard to believe unless you're comparing different bullets. Especially at 100 yards. If there is a large difference in velocity, it may be enough to reduce the BC so that a slower round prevails, but not within 100 yards. I would bet that the WSM round has a bullet that is much less aerodynamic than the other. I have compared this facet of rifle cartridge ballistics many times with many different cartridges, and to have a slower round overtake a faster round USING THE SAME BULLET is VERY rare. If you are not using the same bullet (same Ballistic coefficent) then the comparison is moot, and muzzle velocity is the only thing you can compare. It is easy to find a bullet in one category that outperforms one in another cartridge. I could take a .308 with a ballistic tip, and pit it against a flat nose from a .30-06, and after a little distance, the .308 would be ahead.
As far as velocity not living up to published specs, I would agree. Most regular magnums have 24" barrels, whereas almost all the Winchester and Browning WSM rifles have 23" barrels.

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Location: Missouri/Arkansas
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WSM performance comparisons:

Even with 160 grain bullets of the same general design, the 7mm Rem. Mag catches up and overtakes the 7mm WSM within 100-200 yard of the muzzle.

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WSM performance comparisons:

Thank you for the write up CaptO, good info!

I too found the "catching up" comment strange. If the same bullet is used in both (having the same BC), then the only explanation for this is that the WSM is retarding the bullet more than the REM while it travels the barrel. Retarding meaning increasing the BC of the bullet.

That means that the WSM is somehow roughing the bullet more and increasing the BC. Thus the WSM bullet exits the barrel with a higher BC than the REM exits the barrel. In other words the change is BC is greater for the WSM than the REM. Like MisterV said, if true, thats not normal. One point that you mention that suggests your right, is that the "catching up" doesn't really occur with the 150 grain but becomes consistently more pronounced at higher bullet weights.

By the way, the REM is not "catching up" what is actually happening is that the REM is decelerating slower than the WSM. I'm sure you realize this, but just thought I would say it explicitly because "catching up" conjures up visions of accelerating bullets in my mind.

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WSM performance comparisons:

Sorry for the ''catching up'' confusion! Another thing about it is the 7 Rem Mag has a bigger case capacity than the WSM and SAUM, which may also account for its better efficiency. I think it's about 83.2 grains, something like that.

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WSM performance comparisons:

1.) Case design means nothing once the bullet leaves the barrel, since the bullet is no longer being acted upon by the powder gases. The WSM case is actually more efficent, because you can achieve the same velocities with less powder.
2.) Unless you use bullets of the EXACT SAME ballistic coefficent, the comparison is invalid. "General Design" doesn't cut it. A Nosler partition and a Swift A-Frame have different BCs, but the bullets are the same general design.
3.) Why would the WSM barrel deteriorate a bullet's BC any more than any other barrel?

The arguments against the WSM line just don't hold up when examined through internal and external ballistic principles.

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WSM performance comparisons:

Just read what I wrote before and realize that I made a typo.

Retarding meaning increasing the BC of the bullet.

Should have been:

Retarding meaning decreasing the BC of the bullet.

Any way, I'm curious about this strange WSM result and would be interested in seeing someone do a side by side comparision with identical bullets from hand loads.

Any reloaders out there with these two cartridge in their possession that can run some of these with a chronograph?

If the WSM is in fact retarding the BC more than other similar cartridge, its important to know, since in this case the higher MV of WSM would be misleading.

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WSM performance comparisons:

A number of tests using chronographs that I've seen do not show where the velocities of the WSMs indicate any efficiency edge. As far as ballistic coefficients go, do you really expect me to believe that there is such a monstrous gap between the 160 grain bullet Winchester loads into it's WSM and the 160 grain Nosler? Hell, they're already loading Noslers into the WSM and in no way do even these exceed the performance of Nosler in the 7mm Remington Magnum. The same goes for the 150 grain bullet. Winchester Power-Point for the 7 WSM and Remington Accu-tip or Scirocco for the 7mm Remington Magnum. Both calibers, 150 grain pointed bullets. The comparison is perfectly valid, as it shows, the WSM does not exceed the 7mm Remington Magnum in any way. The scenario does change when 140 grain bullets are brought into the picture. The WSM does produce better ballistics with these, but this leaves a pretty big question: Just how practical is a 140 grain bullet screaming away 3400 fps in terms of game-stopping power? Not very. It expands too quickly to be used on elk-sized game. With bullet weights 150 grains and up, the 7mm Remington Magnum is the more efficient round. This leaves the issue of accuracy potential. Accuracy is a matter of good bullets fired through good barrels. I've shot groups of about a half-inch at 200 yards at a shooting range in Mountain Home, Arkansas. This from a Remington 700 ADL. The bullets were 154-grain Hornady rounds. Various custom-grade rifles, and also some particularly well-designed and properly maintained barrels, on equally well constructed and maintained rifles, can do even better than this. One fellow in town has a Winchester model 70 in 300 Win Mag that hits the same hole every time. Just because you're using a cartridge that has sharp shoulders, is shorter than average, goes by a fancy-shmancy name, and headspaces off the shoulder rather than a belt, doesn't mean you have bought accuracy and excellent perormance itself. Internal ballistics don't mean as much as results do. I've seen several of these rifles on the range. They are not magic, and they don't do anything the regular magnums, and a few standard cartridges, don't do as well or better. The groups tell a pretty darned big piece of the story all by themselves. It's easy to get twisted and tangled up in technical detail, and its easier still for those details to be spiced up plenty. But one cold fact remains when all this is said and done. The groups don't lie.

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WSM performance comparisons:

1.) Case design means nothing once the bullet leaves the barrel, since the bullet is no longer being acted upon by the powder gases. The WSM case is actually more efficent, because you can achieve the same velocities with less powder.

One more thing, if you don't mind. This entire little ''explanation'' is, well, contradicting. See, what it's got me wondering, in conjuntion with something you said in your other post. What I'm wondering is, if case design doesn't matter, and obviously the bullet isn't being acted on by gas expansion anymore, then how could the WSM's case be more efficient? Since by the time the bullet actually reaches the game animal, exactly what case the bullet came from shouldn't really mean anything, should it? At least, going by what you're implying.

Second thing, and equally relevant, you said in your first response that you believed the part about the velocities not quite being up to par with the ads, being due to the slightly shorter barrels on the WSM rifles. Then in this latest, you said this: ''The WSM case is actually more efficent, because you can achieve the same velocities with less powder.'' If having a shorter barrel truly compromises velocity, and accounts for the shortcomings of the short mags, how does a bullet, with less charge, and already supposed to give the same velocity as the full-lengther, how would this, from a 23-inch barrel, compete with a bullet that does pretty much the same velocity, from a 24-26 inch barrel? How did we get from having less velocity due to a slightly shorter barrel, to producing the same velocities, with less powder, yet from that shorter barrel, which is supposed to lower velocities? Basically, it looks to me like what we're up to is, case design doesn't matter beyond the muzzle, that kills the whole thing about the case-efficiency bit, and the 23-inch barrel impedes the round from achieving the velocity of a round fired from a 24-26 inch barrel, and, obviously then, less powder means even less velocity.

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WSM performance comparisons:

FIRST of all...YES the 23" barrel will lose some velocity compared to published tests, just as a 26" barrel will be higher. HOWEVER, I was addressing YOUR statement that the muzzle velocites of the WSMs is HIGHER. So WHICH velocites are you using? Real world or ballistic tests done with 24" barrels? I thought you were comparing the ROUND, not the guns they are fired in. If you are truly objective in your comparison, then barrel length needs to be equal, as it is in factory testing.
SECONDLY...the power-point has a very poor ballistic coefficent compared to other bullets. In order to have a legitimate comparison, the bullets MUST be identical. I don't know how many times I have to say this. ALL OTHER COMPARISONS are invalid.
THIRDLY...my statement on efficiency is definitely not contradictory. The casing's measure of efficiency is only during the bullet's acceleration, while it moves from case mouth to muzzle. For argument, let's say that both rounds generate 3000 fps with a 180 grain bullet (again, YOU said the WSMs generate higher MV, and published ballistics confirm this, using 24" barrels) ...but the 300 WSM does it using 10 grains LESS powder. Isn't that more efficient? If not, then what is it? Once the bullet leaves the muzzle, it doesn't matter HOW it got to 3000 fps (except to the shooter buying the powder). All it can do now is slow down. I see no contradiction in this. One is internal ballistics, the other is external. The only difference is that the WSM used less powder.
LASTLY...You don't have to like the WSMs, and its OBVIOUS you don't. To tell the truth, I haven't made up my own mind yet which rounds are better. I like the short action of the WSM, but I like the better selection of factory rounds in the original magnums. MY ONLY CONCERN IS THAT BOTH ROUNDS BE TESTED EQUALLY, and so far you have proclaimed results based on flawed or manipulated data. Objective data exists, produced by FEDERAL, WINCHESTER, and many reloading manuals. Since most factory-loading companies test using 24" barrels, all you have to do is find where they've loaded the EXACT same bullet into one of each, and then compare!

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WSM performance comparisons:

Like I said before, no, you do not have to use the very same bullet. Two pointed bullets, same weight, same general caliber (.284 and .308, respectively), close enough. MY POINT IS, it's a lot easier to find 7mm Remington Magnum ammo that outperforms the short mag than vice-versa. It also handloads hotter, as I said before and this is a fact. and at realistic hunting distances (those at which game animals are shot), as opposed to at or near the muzzle, what's more important is not what the name of the caliber is, where it headspaces from, or its case design, what matters is which round has more energy and velocity remaing at that distance. For most ammo, that one goes to the 7mm Remington Magnum.

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