Home Forums Hunting & Shooting Ask The Gunwriters Mule Deer - .338win question

CRS,

Let me start my reply to your claim "bigger diameter bullets hit harder. If the only variable changed is bullet diameter, laws of physics dictate that" by pointing out that .338 bullets are .03 of an inch larger in diameter than .308 bullets. Wrapping a stiff business card around a .308 bullet will add that much.

This slight extra diameter does not contribute anything tangible to "hitting harder" or "killing power." Instead the diameter that really matters is the size of the "mushroom" on expanding bullets, because that's what makes the hole in big game vitals.

This varies far more than 3/100ths of an inch in bullet diameter. In fact I've measured the expanded diameter of recovered bullets that started out as .308's or .338's, by averaging the narrowest and widest points of the mushroom, and can't find any significant difference--except between brands. In other words, a .308 bullet that expands into a wide mushroom (say a Swift A-Frame) will be wide than a .338 caliber bullet that doesn't expand as widely. As a result, the difference in expanded diameter between .30 a .33 bullets overlaps considerably, and so does the amount of internal damage they do.

Let me also present a little history of the .338 Winchester Magnum. It was essentially the result of Elmer Keith's insistence that heavier, moderate-velocity bullets killed large game better than lighter, faster bullets. This was certainly true with the cup-and-core bullets he grew up with, and was the reason he eventually helped develop the several .33-caliber wildcats that resulted in the commercial .338 Winchester Magnum. But even Keith made no vast claims about the additional "killing power" of the slightly larger bullet diameter. Instead he settled on .33 because of older British .33 cartridges, which allowed 250-grain spitzers and 300-grain roundnoses to be used, much heavier than anything that worked in .30 caliber. These penetrated deeper than .30-caliber bullets, because they were slower and heavier.

In fact, Keith was originally a fan of .35 caliber, using the .35 Whelen considerably before going with .33, because .33-caliber bullets had higher ballistic coefficients so worked better at longer ranges. The SMALLER diameter bullets of the .338 Winchester Magnum were a solution to the deficiencies of cup-and-core bullets and long-range ballistics.

Now let's skip ahead to 2018, 60 years after the .338 Winchester was introduced. There are so many "premium" (or if you prefer, "controlled-expansion") bullets available these days that most .338 users don't even choose 250-grain bullets, instead using various lighter premiums. The recent elk-rifle poll on the Elk Hunting Forum reflects this: The average weight of bullets chosen by .338 Winchester magnum users was slightly under 220 grains, because of the large number of hunters who chose 200-210 grain bullets over the small number who chose the "traditional" 250-grain bullet, picked by Elmer Keith as the minimum suitable for .338. (When Winchester first introduced the .338, they asked Keith whar bullets they should load. He suggested a 250-grain spitzer for long-range shooting, and 275-300 grain roundnose for moderate ranges. Winchester also added a 200-grain spitzer at 3000 fps, and Keith just about went ballistic, if you'll pardon the pun.)

Most .338 users now choose 200-210 grain bullets, which don't have any particular advantage over premium 200's in the .300 magnums, because today's premium bullets of both diameters penetrate more than deeply enough on elk. We can argue about the tiny difference in initial bullet diameter (or the tiny difference in ballistic coefficient) which favors the .30's, but in reality they're very close to the same thing, bullets of around a third of an inch in diameter, weighing around 200 grains, shot at around 3000 fps.

This doesn't mean I believe bullet diameter doesn't make a difference in "hitting power." I just don't believe there's any noticeable difference between .30 and .33 in cartridges of about the same external ballistics, because of observing the results of each a LOT over the past 30 years.

However, the same observations have led me to believe that MAYBE there is a difference once bullet diameter is over, say, .35, especially when combined with heavier bullets in the 250-300 grain range Keith felt worked so well. I emphasize MAYBE because the animals I've seen such several 9.3mm and .375 cartridges used on do not always act overwhelmed. These have ranged in size from African springbok (a little smaller than American pronghorn) to some animals well over 1000 pounds, including plenty in between.

"Negative" examples would be a pair of springbok taken on a cull hunt in South Africa with a .375 H&H, using a pre-production 260-grain bullet at 2700 fps. They showed up about 100 yards away, and since this was partly a commercial meat hunt I aimed behind the shoulder of one. It dropped, and the other springbok ran a few yards and stood there, confused, so I shot it in the same place. That one ran about 100 yards before falling. Both had holes through their chests that would accommodate one end of an American footbale edges of the lungs, probably because he was flinching, due to being eyebrow-battered on almost every shot by the scope. That's also just one of a number of instances that makes me doubt the common claim that magnums help make up for poor shot placement.

My old zoology professor at the University of Montana, Phil Wright, once got to go along and record the results a killing power experiment in the 1950's, where elk needed to be culled on the National Bison Range near Moiese, Montana. The shooter was a very good shot, and they decided to use two Model 70 Winchesters, one in .30-06 and the other a .375 H&H. Back then the only "premium" bullet available was the Nosler Partition, which few hunters had even heard of. They used Winchester factory ammo loaded with 220 and 300-grain roundnose bullets, both getting around the same moderate muzzle velocity. A dozen elk were shot with each rifle, from mature cows to big bulls.

Phil wrote up the results in an AMERICAN RIFLEMAN article that appeared in 1958. He gave me a reprint of the article, which recorded shot placement and damage, how far each elk traveled after the hit, and other details. The conclusion was the .375 H&H's only discernible advantage was more frequent blood trails, which might be needed, because the .375-killed elk traveled a few yards further before falling. (I lost the reprint a while back, but since then have collected old AMERICAN RIFLEMAN's going back to the 1920's, including the issue with the article.)

Above .40 caliber and there's more often a noticeable difference in how hard bullets hit, partly because they're bigger in diameter, but also because they're heavier.

I also don't think most hunters are very analytical about shooting results, often remembering "examples of one" that prove their prejudices about various rounds (and bullets), and especially the results of different shot placements. Examples of one don't mean much when compared to the results from far more animals, which tend to even out the vagaries of shot placement, and how individual animals react to the shot.