17hmr Penetration Testing

[DiRTY DOG]

There is a lifetime's worth of reading about the 17HMR on the internet. But actual expansion/penetration testing of the 17HMR is scarce.

So I did my own. I soaked a bunch of phone books in water overnight. Wet phone books are slightly more dense than real flesh but it gives you a pretty good idea of how much penetration rounds will give you and how the bullets fragment or mushroom. Each soaked phone book is about 1" thick. I stacked them in a row and shot them. I tested at both 50 yards and 100 yards and found that the results were nearly identical (100 yard tests showed slighly less penetration but the damage looked pretty much the same), so I only posted pics from the 50 yard test.

Marlin 917V

 

[DiRTY DOG]

What I found was that the 17gr Vmax and TNT bullets start to fragment after about 1/2" of penetration. The fragmentation is quick, and complete. Both bullets pretty much completely disintigrate within the fist 2" of penetration, with small shrapnels of copper jacket being left behind. It appears the bulk of the damage from the bullet appears at a depth of 1.5-2". The heavier shrapnel and fragments of both bullets continue through to 3" of penetration, although the TNT fragments are larger. The Vmax bullet has a slightly thicker base that penetrates slightly further than the TNT bullet to a depth of about 4". Both bullets are completely fragmented.

The 20gr XTP bullet is slower to expand. It appears to start at about 1" and be completely expanded by the time it reaches a depth of 2". After that it continues penetrating to a depth of about 5" but there is not much distruption past 2", it pretty much just punches a small hole. The XTP bullet really does mushroom like a big game bullet and stays intact.

Wet phone book material is perhaps 25% more dense than small game flesh according to my testing. So in real animals you'd see a little more penetration than my testing shows.

In summary, on small game, I would expect the 17gr bullets do a lot of damage to a depth of 1 to 3 inches and a small base penetrates to about 4 maybe 5 inches. The 20gr bullets expand like a miniature big game bullet within the first 2-3 inches but mostly just punch a small hole to a depth of about 6 maybe 7 inches.

 

[DiRTY DOG]

At the 50 yard line.

Each phone book is about 1" thick.

 

[bigsky_songdogs]

nice test

 

[DiRTY DOG]

In all of these photos, the top 3 bullets are 17gr Vmax, and the bottom 3 bullets are 20gr XTP.

 

[DiRTY DOG]

 

[DiRTY DOG]

The 17gr Vmax and TNT bullets completely fragmented. All I could recover were tiny bits of jacket and what looked like powdered lead.

The 20gr XTP bullets expanded just like a big game bullet and here they are. The one that expanded the least is the one that penetrated the deepest (less surface area to slow it down).

 

[SShooterZ]

Well done DD, thanks for sharing!

 

[kirby]

Thanks for the testing. How do you like that rifle as for accuracy @ 50 & 100yrds? As well as any other pros vs cons.
Thanks

 

[sharkathmi]

Great post dirtydog!!

I am really impressed with those little 20gr XTP bullets.
I never would have thought they would really hold together and react like a real big game bullet.
Thanks for all your efforts and field testing, and thanks for posting.
Real good info!

 

[OldTurtle]

DD, Good Post about a controversial subject....but, one question... Do your neighbors know that it was you that stole all their Yellow Pages???

 

[yfzduner450]

DD, Great post and thanks for doing some great testing. Also, what a great use of those pesky old phonebooks. Since smartphones and google came out, I'm not sure why they still give phonebooks out.

 

[DiRTY DOG]

Accuracy in my rifle has been fantastic since I bought it new shortly after the HMR first came out. I did install a Rifle Basix trigger. Scope is a Simmons Aetec 3.5-12x44AO. In perfect conditions I expect all 5-shot groups to measure less than 3/4" at 100 yards. (3-shot groups regularly measure half that).

Here are all of the targets I shot with the 17 yesterday. The expansion testing took a lot of time so I didn't shoot much. I haven't fired this rifle since fox season ended 8 months ago... Conditions were a shifting 5mph breeze, 70 degrees F. Every 5-shot group I fired was less than 1MOA without exception. Not bad for a $200 rifle.

50 yards sighting in.

100 yards

100 yards

Chrony chronograph data: distance 5 feet from muzzle, 70 degrees, elevation 1000ft.
Hornady 17gr Vmax
2582
2478
2481
2542
2507

Hornady 20gr XTP
2382 2405
2389 2424
2389 2403
2414 2412
2389 2398

NOTE: My old stash of 2006-era Hornady Vmax ammo was averaging 2650fps. This brand new ammo is only averaging 2507fps from the same gun! That's a huge difference! Also the accuracy is good, but it does not seem to be shooting as well as it used to with the old ammo. Maybe I got a bad lot? Anybody else chrono their new production ammo lately?

Last season... 17gr Vmax.

 

[Chupathingy]

This may very well be the most beneficial thread since GC's shotgun load/choke tests! This is outstanding info and far better than S.W.A.G (Scientific Wild Aced Guesses).

I have long thought that the Hummer could quite possibly be the ideal chambering for fox and bobcat, but I would have definately used the wrong projectile (XTP). Looks like the 17gr V-Max is the way to go for them.

Outstanding work bro!


Chupa

 

[kirby]

What senior Chupa said. Make this thread a sticky.

Chupa for President

 

[MPFD]

I think they have reduced the load slightly since the HMR came out. I used to get split necks all the time when I first got my HMR and now rarely see any...

 

[LWILLIAMS]

Great thread. I agree on the sticky comment

 

[CrazyHorse66]

Originally Posted By: Chupathingy This may very well be the most beneficial thread since GC's shotgun load/choke tests! This is outstanding info and far better than S.W.A.G (Scientific Wild Aced Guesses).

I have long thought that the Hummer could quite possibly be the ideal chambering for fox and bobcat, but I would have definately used the wrong projectile (XTP). Looks like the 17gr V-Max is the way to go for them.

Outstanding work bro!


Chupa

I'm not sure I'm following your reasoning.

I want a bullet to penetrate to the vitals and not blow up on first contact with bone.

Those VMax rounds are highly frangible and phone books are highly boneless.

Anyhow, nice thread! And nice job on the foxes.

 

[Chupathingy]

CH, what I meant is by my way of thinking, I can now see that maybe the XTP is sturdier than I thought. I too thought that the XTP would be a little more frangible. Cats and fox being as frail as they are, do you think that the projectile will fail if it doesn't make contact with bone? I would think that 3" of penetration would be about right on a fox or bobcat and the coinciding energy dump would be devastating. I realize that comparing wet phonebooks to living flesh ain't exactly the same, but I think it gives us a little more insight to the terminal performance of the Hummer. I don't know, I just want to separate the facts from the SWAG. I was kinda hoping that you would see this and chime in with you're thoughts, but I can only see this as being a positive.


Chupa

 

[CrazyHorse66]

I've seen the results of good hits in the heart lung area with VMax on large coons in the yard.

It does a great job of turning the chest cavity into mush.

I've also had them splash on ribs and leg bones, leaving a nasty wound that wasn't terminal. These required more effort to kill , and anyone who has tried dispatching a flopping, jumping, biting, wounded animal can testify that it can get messy quick.


On the other hand, I have found that the XTPs provide adequate penetration to reach vitals from most all angles (reasonable of course) and I've never had to apply a second shot to dispatch them. If the death wasn't immediate, then the animal was dispatched without much of a fight by my dogs, or by me standing on them to snuff them out. Then there's the rare one's that I muffed the shot on.... I can't blame those on the bullet.

Granted, these are coons, which are built a little more solidly than fox. I'm estimating that I've killed around 40 with my HMR in the last 4 years....most of them up in a tree.
Foxes are pretty scarce around here, and if I saw one around the property, it would get a pass.

As far as bobs go... man, they are all muscle and adrenalin when hit. I've removed the heart and both lungs on a couple with .223 and they still ran. One went over 100 yds...

I've had bobs in the yard in my scope, but I always gave them a pass. That's just because I like them around, though. I would head or neck shoot them and go for a CNS kill with the HMR if I was to try, just because of the way they are wired.

But that's the story about how I fell in love with the XTP and explains why I'll only headshoot yotes with an HMR. I've never even tried to shoot one through the body, basically because the mass of the bullet is too easy to deflect with bone.


That's just the way I've rolled though.
If someone is having success with a system, I say more power to em.