NO expansion...

M

MandolinMan

New member
hey all,

Recently bought a Sig P938 ( which I'm loving so far) and am searching for the right cartridge for the gun.

After breaking it in with a few boxes of fmj ammo, I loaded it up with Hornady Critical Defense ammo and have been carrying that way for the past week.

Well today I decided to do a little backyard ballistic testing using water to test expansion. ( disclaimer: I'm fully aware that this testing has little 'real world' value as bad guys are not made of water. Nevertheless I consider it a valid indicator of performance under certain conditions. After all, In the early days of FBI ballistic testing, they used precisely the same setup: 55 gal. drum filled with water. )

Anyway, I was surprised to find that the critical defense ammo gave Zero expansion. So I repeated the test with 124 gr. hornady XTP's and some 115 gr. PMC hollowpoints. Results were exactly the same: very deep penetration and no expansion.

In contrast, ALL three of these rounds expanded very nicely out of the longer barrel of my BHP.

My hypothesis: the shorter barrel generates lower velocities which are inadequate for proper expansion.

My question: What rounds should I consider? As I understand, this is a problem universal to short barreled guns.

I need a cartridge that I can depend on to give me at least some expansion. The three rounds so far have been no better than fmj ammo.

Anyway, Thanks.
 
See my post on testing for expansion posted just prior to your post.
Shorter bbls don't = no expansion.
I tested loads in my M-60 3" .357 magnum, G-27 sub-compact .40 S&W, Smith M&P .40 S&W, G-23, .40 S&W, Smith M-15 .38 spl. & a ton more.
Been shooting b-gel & water filled gallon plastic jugs for many years.
The ONLY bullets I've tested thus far that did not expand was Privi .40 S&W 180 grain from several pistols & it acted like hardball.
I have NOT tested Critical Defense ammo much to speak of.
I can't afford to test all the ammo out there.
What works is Federal "tactical" (hate that word tactical) Winchester bonded core, Remington .357 125 gain h.p. & Federal same load, Remington .45 a.c.p. 230 grain h.p. & a host of others.
I've found nothing in 9mm that didn't expand well thus far, including XTP, factory Rem & Win. reloaded 124 grain h.p.
I've found that no XTP reloaded ammo failed to expand in water filled gallon jugs.
 
believe it or not, I've found that a bottle of water set in front of a firewood round offers a very close representation of soft/hard tissue expansion/penetration. using a wood of medium density like tamarack, ignore the water jug and add 30% and that's your real world penetration, expansion is usually dead on. shoot at 25 yards.

I have always had good luck with hornady XTPs and speer gold dots. standard HPs like sierra and others simply explode inside the water jugs. the 1" or so of barrel length that you lose with the sig is not nearly enough velocity to matter at self defense ranges. you need a better test medium, switch to a smaller jug with thicker plastics(such as a powerade bottle) and put something behind to catch the bullets and shrapnel like a firewood round or a piece of lumber.
 
I was suprised the Hornady load didn't do as well

They make the greatest bullets on the planet IMHO and many of there designs like the Critical Defense are some of the biggest game changers in the balistics world ever made.

Speer also makes some good products, might want to try their famous Gold Dot line of ammunition.
 
I know this makes me a heretic and I can expect to be burned at the stake (figuratively, I hope). I also confess that I have never shot anyone, and hope to never have to do so.

That being siaid, I simply don't believe bullet expansion is that important, or really important at all. FMJ or solid lead bullets, put in the right place (or wrong place, depending on whether you are the sender or the recipient), will kill instantaneously, and what more is needed? In other places, the expanding bullet will cause greater bleed out, but that is not an instantaneous result and is not going to stop a determined attacker. (There are places where a hit will stop without killing, like the hip bone, but any kind of bullet will do that.)

Jim
 
I'd venture a guess and say it's because the bullets are designed to go through thin barriers such as car doors and auto glass and clothing, without fragmenting or expanding. They're also likely designed to expand after passing through bones like the ribs, as this would be the most effective way to ensure deep penetration to reach the vitals. That's likely why they didn't expand in your water tests. Anyway, it's better that they hold together than expand to early, or break apart. Even if the bullet fails to expand it will make a deep wound and with a pistol the only drawback is you get a slightly smaller hole.
I'd much prefer a smaller hole that goes all the way through than one that does not go deep enough, personally.
 
...the same setup: 55 gal. drum filled with water.
Click to expand...
Is this what you used for your testing?

Whether you used a steel or plastic 55 gal. drum, I'm not terribly surprised to hear that the rounds didn't expand. Steel can be hard on bullets, and I would imagine that the plastic of a plastic 55 gal drum is thick enough to plug a hollowpoint.

The priority of most premium self-defense ammo design these days is to insure sufficient penetration to meet the FBI minimum even after passing through a barrier. The result is that it's not uncommon to find that the bullets are constructed so that intermediate barriers won't prevent sufficient penetration to meet the minimum.

However, it's hard to make a bullet that will defeat intermediate barriers AND penetrate well AND still expand. Something has to give and because defeating the barriers and penetrating sufficiently are non-negotiable, sometimes expansion after defeating barrier is compromised.

Try your testing again with water in large zip-lock baggies or using bottles that have thin walls.
 
I carry the same ammo in a Kahr (3.5" barrel). I think the 938 has a 3" barrel.
Could it be that the your gun and ammo combination does produce the velocity required for expansion of the hollow point?
 
It might just be folly to ever completely depend on any piece of equipment, ammo included, or maybe especially.
Like James K said, expecting particular results from any bullet design might very well be disappointing, and no substitute for the skill (or lack of it) of the person behind the gun.
 
g.willikers: You aren't completely depending upon a piece of equipment as you tested it to learn & that's commendable.
I feel h.p. bullets need to expand as advertised & testing gives you a measure of piece of mind.
I never shot anyone in the 22.5 yrs of police work tho I could have, perhaps even should have, but I thank God that I never did.
It's aweful when a cop shoots someone in an environment where it makes the news, you get interviewed, a grand jury rules, you wil get sued, you relive it all over again.
That likely won't happen in the military in a war.
My Sgt. did kill a guy, shot him 3 X with a Colt snubbie using .38 spl. +P ammo. Close range, maybe 10 feet.
Righteous shoot all the way.
I photographed the post. All 3 bullets DID expand, stayed iniside the perp.
The Colt wasn't rated for +P & believe it or not the frame was CRACKED
& the weapon was retired.
It's important that bullets perform in an environment where bullets flying where not intended can result in unintended consquences.
 
I remembered something.
I shot a deer with my 4506 using 185 grain h.p. +P Remington bullets at about 15 feet as the deer was tearing up a barber shop.
True story.
I hit it behind the shoulder as taking a head shot on the panicked deer was problematic at best, letting it out the back door was no solution either.
It broke it's jaw busting into the shop.
Shot #1 knocked it down, it got back up almost dead, shot #2 in nearly same place killed it.
Both bullets recovered expanded real classic mushorrom shape under far side skin.
 
That must have been more than a slightly exciting day.
Did you get any free haircuts out of it, at least?
In that situation, non expanding bullets would probably have been a danger to anyone on the other side of the deer.
Does anyone know how far non expanding handgun bullets actually travel, or how much energy they retain, after exiting a human or animal?
 
Last edited:
Exciting day????????????????????
I had a LOT of exciting days.:( Ever dodge bullets? Now that is exciting.
Ever dodge a knife thrust? A beer bottle, a baby? A BABY????
Yup, a baby. Drug addict mom threw the infant at me. Infant o.k. caught as it as it bounced off the back of the couch then I slapped hell out of the mom!!!
So sue me! Took her to jail & took her kid to.
She did "parenting" classes & got the kid back!
I digress. One of my patrol officers shot a guy with his issued M-66 with issued 125 grain +P h.p., in the meaty part of the thigh.
Guy was running from a burglary/rape attempt, the victim being 89 yrs old!
I interviewed the perp getting treated in the e.r., in considerable pain, the bullet passing right past the big leg bone.
Exit hole was quarter sized, no idea where the bullet went but likely into the ground someplace.
Most gunshot victims I've dealt with were shot with the .22 r.f, the .25 auto, occasional .32 auto, & predominant SHOTGUN. Little doubt about shotgun wounds either.
One suicide by 9mm hardball right thru the brain & the guy lived 2 days in a coma.
I have lots of gunshot stories. Not a good thing ya know.
 
Well today I decided to do a little backyard ballistic testing using water to test expansion. ( disclaimer: I'm fully aware that this testing has little 'real world' value as bad guys are not made of water... )
Click to expand...

If a bullet is going to expand it's going to expand best when shot into water.

The density of human soft tissues is nearly the same as water, which makes sense because most soft tissues are mostly water.

The difference between water and soft tissues is that water doesn't support a shear force. More info here - "Extract from 'Wound Ballistics Misconceptions.' (Duncan MacPherson, Wound Ballistics Review, 2(3): 1996; 42-43) - http://www.firearmstactical.com/tacticalbriefs/2006/04/03/0604-03a.htm (Scroll down to the end of the page to find this paragraph)

I was suprised the Hornady load didn't do as well

They make the greatest bullets on the planet IMHO and many of there designs like the Critical Defense are some of the biggest game changers in the balistics world ever made.
Click to expand...

Hornady Critical Defense and Critical Duty appeal to the uninformed and gullible who fall for Hornady's disingenuous marketing hype that modern JHP pistol bullets routinely fail to reliably expand in actual shootings. Nothing could be farther from the truth.

I'd venture a guess and say it's because the bullets are designed to go through thin barriers such as car doors and auto glass and clothing, without fragmenting or expanding.
Click to expand...

Unfortunately your guess is incorrect. Hornady Critical Defense ammunition is not designed to perform well against light barrier materials. See "A Word of Caution about Hornady's Critical Defense Handgun Ammunition" - http://www.firearmstactical.com/tacticalbriefs/2006/04/main.htm

They're also likely designed to expand after passing through bones like the ribs, as this would be the most effective way to ensure deep penetration to reach the vitals. That's likely why they didn't expand in your water tests.
Click to expand...

The reason why it didn't expand is because the short barrel didn't allow the bullet to be propelled with enough velocity to produce expansion.

Expanding bullets don't have a "delayed expansion" feature - they either expand immediately upon penetration, when velocity is highest, or they don't.
 
I carry GoldDot 124 (not +P) because they expand from an under 4" barrel w/o excessive muzzle blast. Fairly tested against others in water, wet newsprint, and meat, I've determined them to be what I stake my life on.
 
mandolinman said:
I need a cartridge that I can depend on to give me at least some expansion. The three rounds so far have been no better than fmj ammo.
Click to expand...

Why is it so necessary that you have expansion? Expansion and penetration are trade-offs in a marginally powered round like a .380. More expansion = less penetration.

A .380 is fairly marginal on penetration to start with. If you absolutely MUST have expansion for some goofy reason then use something like a Glaser. Other than that, all of the name brand performance ammo is so close that no one you shoot will know the difference.
 
Why is it so necessary that you have expansion? Expansion and penetration are trade-offs in a marginally powered round like a .380. More expansion = less penetration.
Click to expand...

The Sig P938 is a 9mm.

While the 45 auto has proven itself effective over the years with non-expanding ammo, the 9mm has not. It seems the 9mm was little more than a joke until modern expanding ammo hit the market in the 1980's. In recent years with the high quality expanding hollowpoints available like the Speer gold dot, Corbon 115+p, etc, the 9mm has proven itself to be on the same tier of effectiveness as .40 S&W or .45 auto.

So yes, I believe expansion to be important in 9mm. In my longer barreled
9mm's I've found rounds that both feed reliably, penetrate adequately and expand nicely. The intent of my first post was to find out if its possible get these same qualities in a short barreled gun: Expansion AND penetration.

Correct me If I'm wrong, but here's my line of reasoning:

I fire the same round, from the same distance, into the same testing medium. The Only difference being the firearm its fired from. One has a 4.7 inch barrel, the other a 2.7 inch barrel.

From the longer barrel all rounds tested expanded fairly well. From the shorter barrel non of the rounds showed ANY expansion and penetrated fully twice as far.

Not having a chronograph I can't say for sure, but I'm positive the deciding factor was velocity. The shorter barrel failed to generate enough velocity for expansion.

Would a +p cartridge give a large enough increase in velocity out of a short barrel to initiate expansion? I think that's what I'll test next.

For some of you, maybe I'm overthinking it. Perhaps I am. But I'm enjoying the testing and learning quite a bit along the way.

Apologies for the long post. Would appreciate your comments
 
You must log in or register to reply here.
Back
Top