To this point in blog writing, I’ve treated this topic quite fully and fairly, I believe. Though I could be mistaken as the Super Mediums have barely occupied a short paragraph. The excuse being that apart from data in manuals, and the writings of a few authors, I have experience with only one — that being the .340 Weatherby Magnum. And that one has been given reasoned exposition based on considerable personal handloading and hunting experience. So anything that is comparable has purposefully been mostly ignored. This time around I’ll give them a polite nod.
For newcomers and occasional readers of my “stuff”, a timely reminder of what I consider “mediums” would be fitting. Starting at .338-caliber and 4000 ft-lbs at the muzzle, we’ll end at .375-caliber and whatever is deemed “reasonable” in kinetic energy.
In the past I’ve excluded the super .375s, i.e. .375 RUM and .378 Weatherby, and any “wildcats” of their ilk, as they contend with the true Big Bores for recognition in kinetic energy, but NOT necessarily in effect. I don’t believe that any .375-caliber can produce the same effect as a .500-caliber (as one example of a Big Bore) when each has done its “best”, no matter an extra 200 or so fps at most ranges for the Super .375s.
If penetration alone were the “name of the game” then a 6.5, 160gr solid would suffice in most situations. But since penetration is only part of the story, some of us believe that a larger hole in flesh and bone in a vital area is the rest of the story. So a .338 to .375 have distinct advantages over .264 caliber. And where needed or wanted, Big Bores have distinct advantages over all others in wound cavity and destruction of flesh and bone. Of course I agree… bullet speed and construction at impact cannot be ignored, even if we try to ignore them!
That was my “short ‘n sweet” preamble.
What about .323 (8 mm) caliber? It’s sort of in “no man’s land”, as I view it. At one time I was somewhat fascinated with the 8mm Rem Magnum, but few adequate bullets were available for the handloader, and factory ammo was poor in comparison with .300s and .338s.
I originally started mediums at .358 caliber but later relented to allow .338 caliber into the fold. That being .338s that could muster 4000 ft-lbs at the muzzle, which the .338-06 couldn’t do, though being a good hunting cartridge for most N.A. big game at reasonable ranges. But despite comments by noted authors to the contrary, it can’t keep up with the .35 Whelen when barrel length, psi and bullet weights are the same — AND the best powder is used in each.
So let the games begin!
In .338 CALIBER the following cartridges get recognition if handloading data is available in three of the reloading manuals of recent times in my library: BARNES, HORNADY and NOSLER, and make at least 4000 ft-lbs at the muzzle when handloaded.
Any others basically imitate those two in ballistics, and I’ll explain my reasoning as we move along. Those are chosen as they depict the two main classes of .338 magnums. All others are similar to them with the possible exception of the .338-.378 Weatherby. If we include it, then we have three representative cases in progression of capacity.
The .338 Winchester Magnum was introduced by Winchester in 1958, two years later than the .458 Win Mag, and based on that case, 2.5″ in length, necked down to .338″. Case capacity is only slightly less than the much longer .375 H&H and nearly as powerful in kinetic energy when the best handloads are employed.
Factory ammo has varied over the years. Standard velocities today are 2960 fps for 200s/3890 ft-lbs, and 2660 fps/3927 ft-lbs for 250s. At one time there was a 300gr advertised at 2430 fps/3933 ft-lbs, all from a 24″ barrel. There are several variations in factory ammo today. Much of it is in 225gr advertised at 2760 fps/3805 ft-lbs. Also a 210gr is promoted at 2880 fps/3867 ft-lbs. Apart from standard ammo, there have been other “premium loads” promoted at higher velocities and energies than the standard group.
As to handloads, several manuals come close to its true capabilities, always with a cautionary approach for fear of litigious actions against them.
Personally, I’ve considerable experience with two owned .338 Win Mags, and a third owned by my son, Phil. Barrel lengths were from 20″ to 26″; one of each, and my son’s was a standard 24″. From those experiences I learned that barrel length does make a difference — and sometimes a considerable difference. So, I’m reluctant to be dogmatic as to what a .338 Win Mag will “do” without qualifications, as there are many, many variables involved.
For example: from the .338 SAKO FS, 20″ barrel (similar to the pic above), and after a few years of work with it, and other powders and bullets becoming available, I was able to achieve a high of +2700 fps from the 250gr Sierra BT. Did you notice that was from a 20-inch barrel? On the other end of matters, from my 26-inch Browning A-Bolt SS, LH, it reached 2842 fps from a 250gr Hornady SP and a “book load! Now that’s nudging low-end .340 WBY territory! How many grains of “what” powder? 74 grs of RL-19, ignited by WLRM primers!
So the disparity between a 20″ and a 26″ = +/- 138 fps, or 4483 ft-lbs minus 4046 ft-lbs = 437 ft-lbs in that one example! So who wants to be pontifical over the power and reach of a .338 Win Mag without qualifiers? Not I! Phil’s moose hunting load was a 250gr Hornady SP at 2735 fps. It worked well, though I’m quite certain it could have attained +2750 fps without sweating.
The .338 Winchester Magnum is quite popular, considering that the majority of hunters/shooters are into small and sub-medium rifles/cartridges. And that popularity for use in anything from deer to brown bear hunting in N.A. has spurred a further proliferation of light premium projectiles all the way to long-range bullets such as Nosler’s LR and AccuBonds with a BC of .575 for the 250gr. And others are keeping up with their editions of LR projectiles, as well as light-for-caliber bullets with excellent construction and shape. So it’s not only possible to employ your .338 Win for smaller game than was though “normal” in the past, but very appropriately! The .338 Win is not going away any time soon! One could do a LOT worse than choosing a .338 WIN as an all-purpose rifle for anything from coyote to brown bear — when handloaded.
The .330 Dakota fits, more or less, within those ballistic parameters with the best handloads in equal length barrels. Of course, rifles, factory ammo and brass will not be abundant nor cheap.
The .340 Weatherby Magnum: This one came into the world by Weatherby in 1962. Some say in response to, or to compete with, the growing popularity of the .338 Win Mag. Whatever the reason, it offered considerably more in ballistics than the .338 WIN. In factory guise it claimed +200 fps over the Winchester version shooting a 250gr at 2860 fps/4540 ft-lbs from a 26-inch barrel. I have not read any reports for or against that claim. One thing we do know, however, is that across the board Weatherby’s ammo was hot-stoked!
Today, Weatherby claims 2950 fps/4830 ft-lbs for some of its 250 grain loads in the .340. While having only fired a single factory 250gr load of the originals in my .340 Wby at about 2850 fps, I well know that +2950 fps from 250gr Nosler Partitions is easily attained from best handloads. In fact, for many years my hunting load was a 250gr Nosler Partition at +/- 3000 fps/4995 ft-lbs from a 26″ Browning barrel. That exceeded the 26″ .338 Win Mag by 158 fps after it was rechambered to .340 WBY. To simplify matters, that means that what the .338 Win could do at 400 yards, the .340 could do at 500…. And so on.
250gr Hornady SP @ 2945 fps into 7/16″, 87 grs RL-22
250gr Hornady SP @ 2790 fps into 3/4″ at 300 yards! 87 grs AA3100
200gr NBT @ 2175 fps into 1.5″, 80 grs 8700 (fireforming & hunting)
225gr Hornady @ 2855 fps into 3/4″, 83 grs AA3100
*Those represent some of the best of three shots @ 100 yds. Nonetheless, I used the 250gr Nosler for moose hunting at 3000 fps average over several years into 1.25″ for three at 100 yards. I shot my bull moose with that load. All brass was fireformed .375 H&H, once fired Remington. Primers were WLRM.
What the .338 Lapua and RUM will do is largely represented by what I achieved with the .340 Wby Mag.
A few years later I had the opportunity to purchase a .338 RUM or a 9.3 x 62. I chose the latter and have never looked back.
The .338-.378 Weatherby: I include this one because Weatherby still produces them, and there are a few out there.
Nosler’s ballistics in their Reloading Guide 6 is not that impressive. Perhaps that represents all their testing personnel could endure! Regardless, their best for the 250gr Partition isn’t much better at 3034 fps than what I was getting from my .340 at 3000 fps. But only four powders were tested and I think it’s likely that it was arbitrarily shut down at 101 grs of IMR7828 as that only gave 90% load density. If 90% represents 3034 fps, then what would 100% give? That might be another 10 grains at an additional 200 fps, perhaps? But not likely of the same powder.
I included it for speculation only, as, personally, I wouldn’t have a use for it. I’d go to something larger in bore — as I already have in Big Bores.
Next up the .35s.