Pressure Points

By Payton Miller

How Different Is Standard From +P Ammo When
It Comes To Your Average Carry Gun?

Here in the US of A, our preeminent “non-magnum” defensive handgun cartridges include the 9mm, .38 Special and .45 ACP. All feature +P versions in more than one bullet weight by more than one ammo manufacturer.

SAAMI’s cut-and-dried specs quantify a +P rating in terms of pressure increase—for the 9mm it equals a 10 percent bump; .38 Special, 9 percent; .45 ACP, a 9.5 percent bump.

Without getting into headache-inducing numbers like 35,000 psi and stuff, we got curious as to what you might expect “out of the barrel”—say, for a given 147-grain 9mm standard pressure load compared to a 147-grain +P? Obviously, we didn’t have the time, ammo and instrumentation required to quantify everything. But what we did do was grab a mix-and-match assortment of same-weight standard and +P loads from different makers to see what we could see.

It was an interesting undertaking, which took place on a broiling hot day in late May up at Crescenta Valley Sportsman’s Club. It was so sunny we actually had to supplement the plastic chrono sunscreens with a long section of cardboard we’d purloined off an old target frame.

We resorted to this on the advice of an electronics-savvy club member after getting some fairly whacky numbers off the chrono (when you see a reading of 1,400 feet per second for a 185-grain .45 ACP from a pistol, you know something’s amiss). There are, of course, obviously factors involved besides the existence or absence of a +P rating. Not all brands chronograph the same (despite having the same bullet weight), nor do all handguns (despite having the same barrel length). In fact, not all chronographs chronograph the same. But we figured even a ballpark comparison might be interesting. Here’s what we used:

Guns: We got hold of a pair of .38 Special launching pads to compare a carry snubbie with a larger “nightstand” type revolver. The 2-inch was a vintage S&W Model 49 Bodyguard while the 4-inch was a K-Frame Model 15. Our 9mm was a GLOCK 17, the (just under) 4-1/2-inch-barreled classic responsible for lighting the fuse on the Great Polymer Explosion. Our .45 ACP was a Commander-size S&W Scandium 1911 with the requisite 4-1/4-inch barrel. We figured it’d be tough to come up with a more typical (and proper) big-bore carry auto.

In terms of velocity, the legendary +P 158-grain “FBI Load” shaded the standard pressure
158-grain RN decisively in a 4-inch revolver. In a 2-inch gun, the difference was considerably
less dramatic.

Browning’s Mk 3 DBM could be the coolest descendant of the original BAR since the Colt Monitor.

Ammo: For the .38 Special, we wanted to go Old School by comparing the classic +P FBI load—a 158-grain SWLHP—with the often maligned standard-pressure 158-grain LRN. And since it seems the hotter stuff in the lighter weight range is now the Big Thing, we checked Federal’s +P HST JHP Micro. It’s a flush-fit, wadcutter-like 130-grain number that looks to be more cavity than bullet and is expressly designed for small revolvers. For our standard pressure comparison, we used Winchester’s delightfully pleasant-to-shoot little 130-grain FMJ.

Our 9mm representatives were in the 147-grain weight class and included Buffalo Bore’s potent +P Outdoorsman Hard Cast and CCI Blazer standard-pressure TMJ. For the .45 ACP leg of our caliber trifecta we used the Barnes +P 185-grain TAC-XP and the standard pressure Speer 185-grain GDHP.

Surprises? Well, the real one was on the .45 ACP side of the ledger. Speer’s hot 185-grain JHP surpassed its +P “weight mate”—Barnes’ 185-grain TAC XP—by 82 fps. In the 2-inch .38 Special, the +P 158-grain’s advantage over the standard-pressure load was 78-fps, considerably less than the 156 fps margin it enjoyed in the 4-inch gun.

The full-size GLOCK 17 got the most out of both 147-grain 9mm offerings.
As expected, Buffalo Bore’s +P offering was faster. Both of these heavyweights
would offer considerable penetration, but for practice, the CCI Blazer TMJ
would be considerably more economical.

What was a bit of an eye-opener was the new 130-grain Federal +P had a 124-fps advantage in the 2-inch gun but only a 78-fps advantage in the 4-inch. It would appear Federal engineers really did tailor it to “Micro” .38 carry guns!

Not surprisingly, Buffalo Bore’s 9mm Outdoorsman +P was right at the ragged edge of “subsonic-ness.” It exceeded CCI’s excellent and economical Blazer by 140 fps.

The difference? In terms of effectiveness, the velocity boost at the less-dramatic levels probably isn’t as critical as other factors—bullet configuration and weight and how they affect expansion and penetration. Then there’s the controllability issue. Recoil-wise, what’s not much of a big deal in a full-size platform becomes increasingly apparent as the gun gets smaller and lighter.

Of the guns/loads used, the only two where the recoil difference between our particular standard and +P pairings was blatantly obvious to me, was with the 2-inch steel Model 49 Smith and the 9mm GLOCK. But nothing was unmanageable, although an alloy J-Frame .38 or an ultra-compact 9mm could prove to be a handful for some folks with the +P’s we used.

Surprise! Our +P Barnes 185-grain .45 ACP offering was slightly “out-chronographed”
by the Speer 185 GDHP. But both offer very efficient bullet configurations and manageable
recoil, even in this Commander-sized Scandium S&W 1911.

Federal’s .38 Special +P 130-grain HST JHP resembles a flush-fit target wadcutter,
right up until you peer into its cavity (below).

Autoloading Awesomeness

I began shooting centerfire rifles back when it was still primetime for bolt-action snobbery. An article of faith was autoloading rifles simply couldn’t hang with Mauser’s Class of 1898 progeny when it came to accuracy. Now, for the most part (emphasis on most), this was pretty much true … on average.

But what made me question this perceived bit of mid-1970’s wisdom was when I was asked to check the zero on the late, great Robert E. Petersen’s pet ranch rifle. Now “Pete,” as many of you may know, had the means and wherewithal to acquire literally any shoulder-mounted firearm made for any purpose.

The rifle in question was a well-used Browning Grade 1 BAR sporter in .243 Winchester. If I remember right, the load was Federal Premium 100 grain. What I really recall, however, was this rifle was a tackdriver—delivering 3/4-inch groups an inch and a half-high at 100 yards with boring regularity. All this without me suffering the indignity of having to manually cycle each round!

Recently I managed to get my hands on an updated version of the BAR, the Mk 3 DBM, with an 18-inch barrel, .308 chambering, synthetic furniture and integral Weaver rail sections on board the receiver. I’ve stuck a Burris Fullfield 2-7X variable on it and will be trying it out ASAP for a future feature (all alliteration and/or rhyming on these premises is purely intentional). This one could be a hog gun and a half—particularly with Browning’s proprietary 155-grain load.


Hanging the Alaskan Hip Holster from the Drop Loop allows
easier gun access if you’re wearing a pack.

Low Gun

If you carry a full-size revolver as your belt gun, a bit of flexibility on how low it hangs counts as a good thing. For those times when having it “high and tight” gets in the way of backpacks or pack frames, Diamond D Leather’s Alaskan Hunter Hip Holster/Drop Loop combo is ideal. Simply unscrew the 3 screws on the back of the holster, attach the Drop Loop and replace the screws. The Drop Loop has 7 cartridge loops to address your spare ammo concerns.

We tried it with a 4-inch L-Frame S&W Model 686 and found it a comfortably sensible item for outdoors use when backpacks are part of your load-bearing agenda. For a more conventional “FBI-ish” strong-side carry (a crossdraw option with a tilt is available for revolvers only), simply remove the Drop Loop. The Drop Loop fits belts up to 2 inches wide and costs $55. The holster itself is $120.

Diamond D Leather
540 Hjellen Dr.
Wasilla, AK 99654
(907) 631-4212
www.diamonddcustomleather.com

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