Wednesday, August 30, 2023

The Pipsqueak 5.56mm, the AR-15, and Relative Power Levels


In the history of the “assault weapon” debate, there has been a lot of squawking from the anti-gun Left about the “horrific wounding power” of the AR-15-pattern rifles and their standard 5.56mm round. Here’s the problem with their assertion: As usual when discussing firearms, the anti-gun Left has no idea what they are talking about. In reality, the 5.56mm round is kind of a pipsqueak compared to a lot of rifle cartridges in common use, especially those intended for big game hunting.

First, let’s look at the basic stats for the AR-15 platform’s usual load, the 5.56mm round, and compare it to the AK’s 7.62x39mm and the United States’ first modern military rifle cartridge, the venerable .30-06. Note: MV = Muzzle Velocity, ME = Muzzle Energy.

Cartridge

MV

ME

5.56mm 55 grain M193

3240

1282

7.62×39 123 gr spitzer

2300

1445

.30-06 150 gr spitzer

2910

2820

Looking at that, if the first two rounds are your primary basis of comparison, I can see how you might think that the .30-06 rolls out some impressive power levels, and in this perspective, it does; the standard mil-spec loads for the venerable old Cartridge, Rifle, Caliber .30, Model of 1906 are tough stuff put up against a typical AR or AK-platform round. And, yes, most standard police/military vests are weak sauce when taking on an ’06 round. But how does the ’06 itself stack up against some sporting cartridges that are in wide use? And bear in mind I’m not comparing the latest, hottest Eargesplitten Loudenboomer Ultra Magnums that the gun magazines seem to monthly tout; these are rounds that have been in wide use in the game fields for decades.

Let’s compare that to a couple of rounds that I shoot and load regularly: the .338 Winchester Magnum and the .45-70 Government.

Cartridge

MV

ME

.338 Win Mag 265 Grain LRX

2800

4200

.45-70 Government 405gr FN

1680

2274

Note that the .45-70 load I cite here is the standard, original black-powder spec load, and so the velocity and energy are low, lower than the .30-06, although I can tell you from personal experience that those big, flat-nose bullets pack a pretty good wallop inside of 150 yards or so and will put down a big, corn-fed Midwestern whitetail right the hell now. But look at the .338 load, this being the load I’m running through my own .338 Win Mag right now; that one comes pretty close to matching the .30-06 on velocity but, due to the heavier slug, produces almost a ton more muzzle energy, almost quadruple the 5.56 round.

To finish up, let’s really turn up the pressure: Here are the stats for the grand old .375 Holland & Holland Magnum and the .458 Winchester Magnum.

Cartridge

MV

ME

.375 H&H 270-grain solid

2690

4340

.458 Win Mag 500 gr solid

2090

4850

While the .375 H&H is a rung or two up the ladder from my .338 handloads, it’s in the same ballpark. But the .458 Win Mag? That’s an elephant-stopper, made as a dangerous game round, turning in almost two and a half tons of energy at the muzzle.

Sporting rifle cartridges, as you can see, routinely turn in some impressive ballistics, compared to the 5.56mm and 7.62x39mm rounds, and if you consult the benchmark work on such things – that being W. Todd Woodward’s annual Cartridges of the World – you’ll see that there are many, many such cartridges in standard production, and even more in the obsolete, proprietary and wildcat realms.

There’s a good reason for this. Mil-spec rifle cartridges aren’t necessarily designed to kill, RHEEEEing by would-be gun-grabbers notwithstanding. They are primarily designed to allow the individual soldier to carry a good supply (I wouldn’t prefer to carry around seven thirty-round mags full of .45-70 loads) and, when applied as intended, to take an enemy soldier out of action.

Sporting rounds, on the other hand, are designed to kill – animals that are, quite often, bigger and tougher than humans. In fact, some of them, including the big Alaskan moose and grizzlies that are often found within a few miles of where I sit at this moment, are a great deal bigger and tougher. Those kills are also often made at some distance; shots out to 300 yards are not all that unusual. (My personal record is a 280-yard shot on a Colorado mulie, and yes, that was with my .338.) More to the point, sporting rounds are designed to deliver a quick, clean, humane kill, which means one must, as Robert Ruark so famously put it, “use enough gun.”

Modern military cartridges are not in the same ballpark as anything much past mid-range when it comes to sporting rifle cartridges. It’s very nearly a difference of kind, rather than a difference of degree; the difference when you’re comparing some of the tougher loads is in orders of magnitude. And it’s not as though any of the rounds I’ve described here are the Hot New Thing; aside from the 5.56mm, the most recently introduced rounds I’ve described are the .338 Win Mag and the .458 Win Mag, which both first hit the market in 1958.

Let’s hope the current crop of nitwits in the Democrat Party don’t figure that out because next, they’ll be raving about “sniper rifles” and “armor-piercing ammo.” Meanwhile, the “assault weapon” issue will continue to be litigated, and the people pushing for bans on such will still have no idea what they are talking about.