Expansion percentage

[nanney1]

Watched a Yeager video this morning on "Pretty Hollowpoints". I'm paraphrasing, but he said that in real life shootings, only 25% of hollowpoints actually expand, and that accuracy is more important that ammo selection. He also said that the lighter, faster 9mm rounds tend to get better expansion due to greater penetration. So, he runs 115 grain as opposed to 124 or 147.

I spent a fair amount of time watching videos before selecting Federal HST 124 9mm as my carry ammo. But, his vid got me thinking. Why worry so much about it and focus more on practicing and being accurate.

So, I was at Walmart today and just looking at ammo. They had Remington UMC 115 grain HP. 100 rounds for $29.97. I thought what the heck, and bought a box. I figure at that price I can actually get some real practice time in with a HP round. I typically only run one mag of the HST's per range session because of the cost and mainly run cheaper FMJ's.

[Dufus]

My thoughts: if anyone depends on a hollow point to expand, they need help.

Handgun hollow points are not dependable in that respect.

I have tested hundreds of rounds in the 45 ACP, 45 Colt, 38 Spec, 380 ACP, and others and have found that one would be just as well off shooting a round nose or wadcutter style bullet when appropriate. Semi-wacutters are the second best. JMHO

[MandolinMan]

He also said that the lighter, faster 9mm rounds tend to get better expansion due to greater penetration.

[Sharkbite]

Watched a Yeager video this morning

And that says it all....

[mete]

You can make a bullet do anything you want ! Speer had a 45 200 grain that had 12 slits in the jacket. Woodchuck hits in the spine/shoulder area would not exit ! An early 9mm Nyclad expanded to .75" through a rabbit . Do you really want to talk with me about expansion ??
The problem in those early days [~ 1970] was consistent expansion and figuring just how much expansion is necessary. Tell the factory what you want and they should be able to make it !
My early experiments show'd me that caliber does matter.

[jmr40]

I have very serious doubts about the accuracy of this.

he said that in real life shootings, only 25% of hollowpoints actually expand,

I know this is completely false.

He also said that the lighter, faster 9mm rounds tend to get better expansion due to greater penetration.

Of course shot placement trumps everything else,and penetration is very important too. But it has been well established that HP ammo is more effective than FMJ at ending a fight sooner. The same hit with a FMJ may end up stopping a fight, but it will take longer for the person hit with it to expire.

Traditionally a 124 gr 9mm bullet @ about 1200-1300 fps has proven to be about as good as anything. Early 115 gr HP ammo earned a reputation as a poor choice. I've seen nothing to convince me that has changed. Early 147 gr ammo was too slow and did not expand well enough. But according to the FBI newer 147 gr loads at near 1000 fps are the best yet. We shall see, but I know I'd much rather have either the 124 or 147 gr load than any 115.

[nanney1]

Well, they did have WWB 147 HP, but it was a 50 round box for around $20. So, I went with the cheaper Remington. I'll probably grab the WWB 147 next time to see how it runs. The likelihood that I'll ever end up in a self-defense encounter is very unlikely, but at the least, I'll have something.

[Bartholomew Roberts]

He also said that the lighter, faster 9mm rounds tend to get better expansion due to greater penetration. So, he runs 115 grain as opposed to 124 or 147.

Expansion increases drag which slows a round down faster and reduces penetration. Plus, a lighter round will shed momentum faster than a heavier round.

[nanney1]

He, Yeager, said he used Corbon 115 for his 9mm carry. But, this could have been one of his older vids that he is uploading to his new account. I don't know for sure.

I just thought the 25% expansion was interesting.

[nanney1]

Ran one mag of the HST and then one mag of the UMC HP's and they were similar as far as accuracy. I'm not a good enough shooter to really tell any difference though.

[Cheapshooter]

He also said that the lighter, faster 9mm rounds tend to get better expansion due to greater penetration.

Not much credibility when he makes statements like that!

[saleen322]

The new FBI 9mm round is a 147 made by Speer. As was mentioned, it averages about 980 fps in testing and does about as close to perfect in the penetration tests through all of the standard mediums that I seen. It handily beat the 9mm +P and +P+ in consistency. I have watched some youtube stuff but it is as likely to be wrong as it is to be right. It seems Yeager may be in the former category if he made those statements about penetration.

[Archie]

I've pretty much run the cycle. (All of this with .45 ACP, by the way.)

When I was but a 'yoot' I had surplus GI hardball. Then I went the way of hollow points of all sorts and kinds. I tried everything. I loaded everything. I loaded everything hotter.

Then the revolver ammunition moved into my thinking. The best penetration on large animals (and that more or less includes humans) is a heavy for caliber wadcutter or semi-wadcutter, jacketed or not.

I am now back to more or less solid acting bullets. I carry Federal Hydra-shok, with the idea it's full weight (230 grains) and the hollow point will either expand a little or the hollow point will act like a solid flat nose pushing everything ahead rather than slipping through.

In a .45 AR revolver, I load a 255 grain .45 SWC, getting around 800 fps. But one can see daylight through the hole. If I could find a .452 cast bullet with SWC configuration and have it work reliably through my autopistol, I leave it alone.

I've left out a bunch of intermediate steps for brevity.

[44 AMP]

Of course shot placement trumps everything else,and penetration is very important too.

Not quite right...you need both, together. Not only does the bullet have to go to the right place, it has to get there, as well.

re: the 1986 Miami shootout, and the "failure" of the 9mm Silvertip round.

Had the bullet penetrated another inch, the odds are high the killer would have been shut down sooner, possibly before killing and wounding several FBI agents.

Placement was good enough, but penetration wasn't. The load passed all tests and requirements of the time, and was thought to be pretty good stuff. And it generally was. In that one real life shooting, however, it wasn't quite good enough.

They have since changed their standards about what is "good enough".

If one of today "approved" rounds fails as spectacularly as that Silvertip did, I expect the FBI will change their standards, again.

It doesn't really matter what your standard is, sooner or later a real world situation will happen where what is promised to work, and expected to work, won't work the way expected, or promised.

[Bartholomew Roberts]

Originally Posted by JohnKSa

Had the bullet penetrated another inch, the odds are high the killer would have been shut down sooner, possibly before killing and wounding several FBI agents.

And to bring us full circle, the 115gr Silvertip didn’t penetrate as deeply as needed because it did what it was designed to do and expanded very aggressively.

[44 AMP]

And to bring us full circle, the 115gr Silvertip didn’t penetrate as deeply as needed because it did what it was designed to do and expanded very aggressively.

And why we keep going around in circles over this kind of thing. When a bullet does exactly what it is built to do, you can't really say it failed. However, in the Miami shootout, what it was designed to do, and did, wasn't enough to stop the attack fast enough to prevent dead and wounded agents.

And its also what you get when bean counters play a part in ammo criteria.

Now, I do understand the real and potential risk to a department from ammo that penetrates "too much" or "too often", but it is, a different level of risk than an individual defending themselves is exposed to.

What is the best choice overall, for dept. issue ammo is something different than what might be the best choice for a private citizen.

Sadly, there is no magic bullet. There is no load that is "just enough" and no more. Everything that has ever been tried to be just enough, and no more has failed in some real world situation were the planned for "just enough" was delivered, but was not quite enough for that situation.

The one thing you can say, with confidence, is that ammo that is made to go all the way through, goes all the way through. Expansion is a nice plus, but its not a minimum requirement of reality.

Now, were I some kind of dept., with perhaps hundreds of officers, who may be involved in shootings dozens of times a year (or more?) then, AS A dept, I would be concerned with the cost of both misses, and "overpenetration", because the odds are high the dept will have those happen, in an area where the background is full of innocent people.

As an individual, private citizen, living in a rural area, and valuing my personal butt higher than any dept.'s budget, I'm willing to take what I see as a TINY risk to others, in order to use ammo that I expect will "go all the way through", and not stop short of getting where it needs to go.

A bullet that gets to the vital spot, but stops seldom delivers the desired result. A bullet that goes through that vital spot, nearly always does.

People who wear a badge are paid to take risks that I'm neither paid, nor willing to take. And God bless 'em that they do so, willingly.

Given the choice (and most aren't) I would choose penetration that will get to a vital spot over expansion that might get to a vital spot.

If a round can reasonably guarantee both, I'm all for it, but if not, I know which one I would choose, and its not the one that "might" get the job done.

[Hal]

He also said that the lighter, faster 9mm rounds tend to get better expansion due to greater penetration. So, he runs 115 grain as opposed to 124 or 147.

LOL! So,in addition to everything else, Mr. Yeager managed to rewrite the laws of physics eh?

Silly me, I was always under the impression that expansion and penetration were diametrically opposed....