Thursday, April 25, 2013

380 Auto FMJ Heavy Clothing Terminal Testing in Clear Gel


You may be wondering why I would bother with such a seemingly uninteresting test.  Really, is there any other ammunition as boring as full metal jacket ammo?  It doesn't expand, fragment, disintegrate, explode, or do any other cool stuff.  I might as well be terminal testing rocks, right?  On the surface all of that is true, but I've always had nagging questions in my mind about 380 FMJ ammunition.  Questions like:
  • How deeply will 380 FMJ penetrate?  Enough, or too much?
  • Is the terminal performance of a flat nose FMJ really better than a round nose FMJ?
  • Are the premium priced FMJ loads better than cheaper target/range FMJ loads?
  • Does a faster FMJ load perform better than a slower FMJ load?
  • What caused the large wound channel that I observed in this previous FMJ test?
In addition to answering my own questions about FMJ terminal performance, I hope to create some new data points for others that have similar questions.  After visiting various internet forums, I've seen folks get tied up in knots over their choice of 380 Auto defensive ammunition.  Others on the forums try to help with the decision making process by providing advice, but that advice is usually split down the middle with one group preferring hollow points and the other group preferring full metal jacket.  These threads usually involve one or more references to various terminal performance tests of hollow point ammunition (maybe even one of mine).  The hollow point crowd touts these tests as proof of excellent performance, while the full metal jacket crowd proclaims the ammunition is garbage due to lack of penetration.

I'm not trying to resolve the 380 Auto JHP vs. FMJ debate.  I'm just trying to plug some gaps in FMJ performance data so people, like me, can make their own informed decisions.

Test Pistol:
Kahr P380 with 2.5" Barrel
  
Test Protocol:
I wanted to do a true head to head terminal test on all five loads so I cast a much larger 18"x11"x4" Clear Ballistics Gel block for this test that would accommodate all five tests without overlapping shots.  The Clear Ballistics Gel block was verified as calibrated to 10% Ordnance Gel density by means of the standard 600 fps BB calibration test.

Each test shot was set up with the same barrier materials in front of the gel block.  I used 1 layer of 5/6 weight Hermann Oak tooling leather and 2 layers of mid-weight (8 oz) denim in front of the gel block.

All test shots were fired from 8 feet over a chronograph that was 4" or less from the front of the gel block.

Immediately prior to shooting the gel test shots, a 5 round velocity average test was done with the same ProChrono Digital Chronograph used to capture terminal test shot velocities.  Due to limited  ammunition supply, one load was restricted to a 3 round velocity average.

Test Results:
I ended up with five complete individual tests conducted under similar conditions.  Rather than make one very long video that wouldn't be watched, each test was documented individually.  Please feel free to watch as many of them as you wish.  At the bottom of the test data sheets, I've included one more blog exclusive video pointing out the highlights of the five tests.  If you are in a hurry, just jump down to that video. 

 
 

Underwood Ammo
100 Grain Round Nose
Velocity < 850 fps
Tumbled
Penetration < 18"
Click Image to Enlarge




Double Tap Ammunition
95 Grain Round Nose
Velocity > 900 fps
Did Not Tumble
Penetration > 18"
Click Image to Enlarge
Remington UMC
95 Grain Flat Nose
Velocity < 850 fps
Tumbled
Penetration < 18"
Click Image to Enlarge









Buffalo Bore
95 Grain Flat Nose
Velocity < 850 fps
Tumbled
Penetration < 18"
Click Image to Enlarge








Buffalo Bore +P
95 Grain Flat Nose
Velocity > 900 fps
Did Not Tumble
Penetration > 18"
Click Image to Enlarge

As mentioned above, I did produce one additional video highlighting the major differences and common characteristics of the tests.  This video is a blog exclusive that won't be going out on YouTube as a public video. 

In the close up photo below, I've identified each round by number.  As you can see I had a good cross section of bullet types represented in this test.
1)  Underwood Ammo 100 Grain RN
2)  Double Tap 95 Grain RN
3)  Remington UMC 95 Grain FN
4)  Buffalo Bore 95 Grain FN - 2011 Purchase
5)  Buffalo Bore +P 95 Grain FN - Current Production


After extensive review of the artifacts left in the gel block, I was ready to propose answers for my original questions.

How deeply will 380 FMJ penetrate?  Enough, or too much?
- In this specific test, we saw penetration depths between 17 to 21 inches.  I'm more comfortable with something on the lower end of that scale.  Depending on your needs, more penetration may be desired.

Is the terminal performance of a flat nose FMJ really better than a round nose FMJ?
- If you gauge terminal performance by wound channel, I would say flat nose was better during the first five inches into the block for bullets that did not tumble.  The flat nose wound channel had visibly more stretch damage than the round nose bullet.  After 5 inches of penetration into the block both wound channels looked very similar.  The one advantage of the flat nose was more initial energy that was dumped into the block faster than the round nose.  Simply put, the flat nose entered faster and stopped quicker than the round nose bullet.

When tumbling took place, the flat nose wound channels looked very similar to the round nose and had similar penetration depths.  I really couldn't declare that one was better than the other.

Are the premium priced FMJ loads better than cheaper target/range FMJ loads?
- Based on this test, I don't see the advantage of premium priced and super fast FMJ loads.  They appear to be more stable and less prone to tumbling allowing them to penetrate too deeply for my tastes.  The good news is that when ammunition supplies return to normal, there are a multitude of 380 FMJ loads available within the velocity range of 850 feet per second.  I pretested many of them HERE.   

Does a faster FMJ load perform better than a slower FMJ load?
- Based on the artifacts left in the gel block, it appears that a slower FMJ load that tumbles will leave a more substantial damage path.  The tumbling also scrubbed off energy and limited penetration to 18" or less.

What caused the large wound channel that I observed in this previous FMJ test?
- Based on the location and size of the wound track artifacts found in the clear gel block, I believe the large wound track in the previous SIM-TEST block was due to a tumbling bullet.  This was the second terminal test with the Remington UMC FMJ FP that displayed evidence of tumbling.

Wrap-up:
If you follow the blog regularly, you may have noticed that I've tested several full metal jacket loads in 25 Auto, 32 Auto, 32 NAA, and now 380 Auto.  Prior to doing these tests, there really wasn't much data available.  I'm not going to push folks to one side or the other of the JHP vs. FMJ debate, but I hope I've provided a more balanced view with sample tests of both bullet types that people can review before making their own personal choices. 





Disclaimer....This test should not be considered an endorsement or recommendation for the product(s) tested.  All tests represent actual performance in ballistics testing media.  Terminal performance in all other media will show different results.  It is up to each individual to make their own personal decision on which specific ammunition to use for their needs.  It's also critically important to test any ammo in YOUR SPECIFIC FIREARM before relying on it for any purpose.

Ammunition labeled as +P or +P+ should only be used in firearms that have been certified by the manufacturer as safe for the additional pressures generated by these ammunition types.

 

1 comment:

  1. Excellent review! I have long preferred FMJ in this caliber if for no other reason than economy and availability. I have two .380's, both with 3.5" barrels. One is a Remington Model 51 which will NOT cycle with anything that isn't marked +P, so that, plus the added barrel length, makes me wonder if I shouldn't use JHP's in it for carry. The Sig 232 will probably still get standard pressure FMJ's, since it is not a locked breech like the Remington.

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