Ballistic gelatin test results : .32ACP (Hydra-Shok, Gold Dot, XTP)

Status
Not open for further replies.

Brass Fetcher

Member
Joined
Jan 11, 2006
Messages
1,686
Location
Bill Clintons old stomping grounds.
This paper compares the terminal performance of a set of .32ACP ammunition (Speer 60gr Gold Dot, Federal 65gr Hydra-Shok, Hornady XTP) fired from a Kel-Tec P32 to various control ammunition, in 20% ballistic gelatin.

There is no significant difference in the wounding ability of the three brands of .32ACP cartridges, and very little improvement in lethality by stepping up to the .380ACP JHP. This is explained further in the report.

The control ammunition was .25ACP Hornady 35gr XTP, .32ACP CCI 71gr Blazer FMJ and .380ACP Federal 90gr Hydra-Shok.

All shots were into 20% gelatin, which is more resistive than 10% gelatin. The penetration depths will reflect approximately 30% shallower penetration depth than 10%.

The data for this report was obtained from a high speed video camera, filming at frame rates varying from 42,000 to 60,000 frames/sec.

http://www.thehighroad.org/attachment.php?attachmentid=142337&stc=1&d=1305684515

Please let me know what you think.

John
 

Attachments

  • Introduction to .32ACP Terminal Performance 06MAY11.pdf
    2 MB · Views: 537
John, as always thank for your time and effort to conduct this test. As a Seecamp .32 and Kel-Tec .32 owner this info is extremely valuable thank you for sharing.

Mike

Do you mind if I post a link to this thread on the Seecamp forums?
 
Last edited:
Thanks for the report John, I have been thinking about this as I carry a P32 everyday. It may have been in your report and I just missed it but what was the test gun and barrel length for the 380 you used for comparison? Also, did any of the ammo brands you test feed more reliably than others? I am planning a feed test on my P32 later this month where I am going to test several boxes of Hornady, Federal and Speer jhp rounds to see if they all feed reliably. Thanks again.
 
chihuahuatn - Please feel free to share the information with the Seecamp forums.

KDS - The .380ACP was a SIG P238, with 2.7" barrel length. As far the reliability of the gun, we typically single-load the barrel when doing gelatin testing. This lets us use a 'real gun' versus a test barrel (which is also real :) ) without the potential to affect the results if the bullet nose is deformed by the impacting the feedramp.

The recoil on all loads except for the Hornady were 'heavy' for this weapon and the cartridge. In fact, the reason for the (2) shot sample on the Hornady XTP was because the 3rd shot fired into gelatin was a defective load - the impact velocity at 10ft was 600 ft/sec.

This caused the bullet to fail to expand in the gelatin. Since this bullet demonstrated an 'operational failure', we took it out of the results.
 
JE223
Ballistic gelatin test results : .32ACP (Hydra-Shok, Gold Dot, XTP)

As an owner of a P-32, I thank you. This was a thorough and well-written review. If I am interpreting the data correctly, .32ACP in FMJ is still probably the way to go???
 
I have to disagree with you here.

The 380 ACP has a bigger wound channel and penetrates 1.5" deeper than 32 ACP.

Where it transfers more of its energy (vital vs. non-vital) areas is irrelevant to me. If it makes it 1.5" deeper, it is more likely to nick the heart or a lung with the sharp edge of the expanded bullet.

Remind me again, what is the approximate ratio of inches of penetration in ballistic gelatin vs. in a human body?

As I recall from other reading, the 380 was decided to be the minimum for adequate penetration.

Of course this varies from shooting to shooting, and as you pointed out, it depends on what it hits when it enters the body and how much it tumbles.
 
The 380 ACP has a bigger wound channel and penetrates 1.5" deeper than 32 ACP.

Yes, the 380ACP JHP tested offers some advantage in penetration. The difference in the expanded diameter of the bullets in .32ACP and .380ACP is negligable.

When facing head-on, the average male torso (United States) has a frontal area of 559 square inches. The average expanded diameter for the .32ACPs is 0.132 square inches, or 0.02% the area of interest as a target. The average expanded diameter for the tested .380ACP is 0.186 square inches, or 0.03% the frontal area of the torso. For comparison, the largest expanded diameter commonly encountered is the 12ga slug, which typically expands to 1.00" diameter, or 0.785 square inches. That is 0.14% the area of the torso. The expanded area of the largest projectile thrown by common small arms is a little bit more than "one tenth of one percent" of the size of the human torso.

The frontal area of a bullet is only important insofar as its influence on the drag exerted by/on the projectile. Duncan MacPherson's data revealed that the diameter of the cavity was about 68% that of the expanded diameter of the bullet, so the percentages given above were generous.

Where it transfers more of its energy (vital vs. non-vital) areas is irrelevant to me. If it makes it 1.5" deeper, it is more likely to nick the heart or a lung with the sharp edge of the expanded bullet.

If the bullet expended 50% of its kinetic energy in the skin and adipose fat of an attacker, is this still acceptable?

Remind me again, what is the approximate ratio of inches of penetration in ballistic gelatin vs. in a human body?

I don't have an answer to that, because there is no correlation. 1" of penetration through the pelvis is much more difficult for a bullet than 1" of penetration through lung tissue. The maximum depth of interest in 20% gelatin is 8.0" ... which equates (with expanding ammunition) to 8.0 * 1.31 = 10.5" penetration in 10% gelatin.

As I recall from other reading, the 380 was decided to be the minimum for adequate penetration.

It's all a balance. Eventually, the madness of needing 12.0" of penetration in 10% gelatin ("or the bullet is no good"), should be replaced by an understanding that handguns are compromise weapons and that they (as well as rifles and shotguns since the target is the same) should be focused on doing significant amounts of kinetic energy transfer in the early (post 2.5" depth) and middle parts of the penetration track. This allows for a greater chance of disabling a body part needed for the attacker to continue fighting. Most structures that can be disabled by a small arm, are easily reachable by most small arms ammunition. Its just a question of how much kinetic energy a bullet is transferring at that depth.
 
John,

Thank you for the report. My P-32 is my EDC. Lately I have been carrying the Hornady 60 gr XTP bullet (loaded by Fiocchi), so I really appreciate the pictures of the XTP bullet expansion. Do you mind if I post a link to your report on the Kel-Tec owners group forum (KTOG)?

Jim
 
JE223 said:
It's all a balance. Eventually, the madness of needing 12.0" of penetration in 10% gelatin ("or the bullet is no good"), should be replaced by an understanding that handguns are compromise weapons and that they (as well as rifles and shotguns since the target is the same) should be focused on doing significant amounts of kinetic energy transfer in the early (post 2.5" depth) and middle parts of the penetration track. This allows for a greater chance of disabling a body part needed for the attacker to continue fighting. Most structures that can be disabled by a small arm, are easily reachable by most small arms ammunition. Its just a question of how much kinetic energy a bullet is transferring at that depth.

I'm not so sure about this. The transfer of kinetic energy is what is perceived as shock or "knock-down power" by an assailant. So if everything else is equal, more is better.

Once the bullet enters the body after that initial shock of going through skin, fat, and bone, I don't think KE matters any more until it hits more bone on the way out. (assuming it exits) Once inside the torso cavity, what matters is how much damage is caused to organs. I believe this to be correlated to bullet diameter at that time, as well as how sharp the "petals" are on the bullet, now how much KE is still being transfered.

After all, how much KE does it take to nick a lung? Not much, I bet.
 
jimk0512 - Please feel free to post the link on KTOG.

Smaug -

I'm not so sure about this. The transfer of kinetic energy is what is perceived as shock or "knock-down power" by an assailant. So if everything else is equal, more is better.

I can understand your confusion. All else being equal, more KE is better.

Once the bullet enters the body after that initial shock of going through skin, fat, and bone, I don't think KE matters any more until it hits more bone on the way out. (assuming it exits) Once inside the torso cavity, what matters is how much damage is caused to organs. I believe this to be correlated to bullet diameter at that time, as well as how sharp the "petals" are on the bullet, now how much KE is still being transfered.

So, it matters in terms of damaging the target in the first few inches, but then KE doesn't matter after that? What unit of measure can be used to quantify this damage?

After all, how much KE does it take to nick a lung? Not much, I bet.

The relevant question is "how much KE does it take to push a given bullet to the depth at which it can nick a lung?"
 
I find it hard to believe there is negligible difference between 32 and 380 caliber.

A good comparison would be equivalent CorBon jhp rounds for 32 and 380.

At 90gr for the 380 round 60gr for the 32, the 380 is 33% heavier than the 32 round and according to the goldenloki gelatin tests the 32cal penetrated just over 8" while the 380 penetrated over 13".

Almost right in line with the weight difference the 380 round penetrated more than a third more than the 32 round.

As far as I'm concerned relevance of energy transfer in these calibers is a fairy tail.

Since you don't sacrifice in dimensions or weight between the two calibers I can't see any reason to opt for less performance in the same platform.
Just my 2cents.
 
Last edited:
Firstly, let me thank you for this great piece of research. Very competently executed, and an excellent resource. Please don't let the comments that follow dissuade you from making other such contributions in the future, or give you the impression that your work is unappreciated. It is.

That said:
So, it matters in terms of damaging the target in the first few inches, but then KE doesn't matter after that? What unit of measure can be used to quantify this damage?
The size of the wound channel and cc's of blood issuing from it.

The relevant question is "how much KE does it take to push a given bullet to the depth at which it can nick a lung?"
This seems like an argument for the .380, as it had more penetration, no?

I'm not saying you're wrong, but the details you've provided about why kinetic energy trumps penetration aren't compelling. Several of the charts show that the KE of the .380 round scrubs off sooner, yet it still penetrates farther. A ballistic gelatin test does not, for me, provide proof enough that a .32 ACP bullet with marginally more KE is substantially equal to a .380 bullet that penetrates deeper in a situation where the more random element of the relative toughness of various vital tissues is thrown into the mix.

BTW, my Seecamp LWS .32 and I WANT to believe. ;)
 
Excellent report. Very clear to read, nice format and packed with a lot of useful info. I admit, I read the first several pages then skipped to the summary. :) Nice work.
 
Longer barrel .32ACPs

Here are a few charts of the .32ACP Federal 65gr Hydra-Shok, .32NAA Federal 65gr Hydra-Shok and .380ACP Federal 90gr Hydra-Shok.

http://www.thehighroad.org/attachment.php?attachmentid=142512&stc=1&d=1305906048

That's just a quick look at data that is part of an upcoming report, but I think it gives some idea as to the effect of longer barrel .32ACP guns.

The .32NAA cartridge, is a .380ACP necked down to fire 32 caliber bullets. Impact velocities for the NAA were, 1070 ft/sec, 1132 ft/sec and 1187 ft/sec.
 

Attachments

  • 32NAA and 380ACP.pdf
    197.8 KB · Views: 47
Just curious, why 20% gelatin?

Each block costs twice as much to produce as 10% gelatin.

10% gelatin would allow you to test in both bare gelatin and clothed/denim covered gelatin for the same cost. Two test events - more data - same cost.

Or with your bare gelatin only tests you can double the number of cartridges you test at no additional cost. Again: more data - same gelatin cost.
 
The 20% is so we can maintain compatibility with NATO standard testing.

Do you have any insight on why NATO uses 20% as apposed to Facklers use of 10%. Which one more accurately mimics bullet performance in live tissue. I'm aware that the 10% is primarily a Fackler created US standard and other countries don't accept it.

Or there any online source that cover the reasons for this difference in standards.
 
The 20% is so we can maintain compatibility with NATO standard testing.

And the value added in using a NATO standard for testing personal defense handgun cartridges is... ?

I'm not busting your balls - I'm just curious.

I thought it might be due to temperature control issues (4 degrees F for 10%; 72 degrees F for 20%*).

* I'm not familiar with NATO standard gelatin. MacPherson (Bullet Penetration, pp 75-76) indicates 1:1 penetration results for 20% gelatin calibrated at 8.0 +/- 0.2 cm.
 
And the value added in using a NATO standard for testing personal defense handgun cartridges is... ?

Because that is the standard that is used for measurement of kinetic energy transfer, measured from a high speed video camera.

I know you're not giving me a hard time ... so I hope the above answer doesn't come across that way. That's just how I type. :).

I've always seen 20-percent blocks at 45 degrees F ... or 7 degrees C. Table 5-1 lists 4.4 +/-0.2cm for 20-percent gelatin at 4 degrees C. The temperature limit of 48degF is used when we test 20%.
 
Because that is the standard that is used for measurement of kinetic energy transfer, measured from a high speed video camera.
Gotcha! ;)

Table 5-1 lists 4.4 +/-0.2cm for 20-percent gelatin at 4 degrees C.
Which is half the calibration penetration of 10% at 39 degrees F. How 'bout that!

Just so others who might be following us don't get confused, MacPherson tested calibration of 20% gelatin at two different temperatures - 39 degrees F (4 degree C) and 68 degrees F (20 degrees C). (He further indicates that 72 degrees F (22 degrees C) provides more accurate penetration results for 20% gelatin.)

Cheers!
 
Status
Not open for further replies.
Back
Top