Monday, September 24, 2012

Gel Testing Speer 9mm Gold Dot vs. Gold Dot Short Barrel


I've always been very curious about the actual terminal performance differences between the Speer Gold Dot Hollow Point and the Speer Gold Dot Short Barrel Hollow Point.  Based on the number of requests I've received to test these two side by side, I knew I wasn't the only one that was interested in this information.  Reading around the internet, everyone believed the Short Barrel loading would perform better in short barreled pistols, but aside from the information available on the Speer website there really wasn't much data available.

Doing a head to head test has been on my radar for over a year, but it never made it to the top of the list.  I got some extra motivation to do the test last week when I started investigating a new ballistics testing product from a company called Clear Ballistics.  I did a blog about the product that you can read by clicking this link if you want more background on the ballistics gel they offer.  The gel and this head to head test just seemed to be made for each other.  As it turns out my gut instinct was right.

I don't remember exactly when Speer launched the short barrel extension to their Gold Dot line of premium personal defense ammunition.  At the time of introduction internet speculation said that Speer had tweaked their powders and bullets to perform better in short barreled pistols.  The Speer website does indeed mention the use of "Low-flash propellant" and "True, bonded-core bullet velocity-tuned for optimum terminal performance".  We all assumed that performance would be better, but we all wondered how much better.

Let's test it and see.
  
Pistol Specs:

Testing Protocol:
My previous testing process changed significantly for this test.  I took two shots at the end of a bare Clear Ballistics Gel block.  I took each shot from 8 feet away and impact velocity is measured 2 inches away from the gel block.  After running the test, I shot a 600+ fps calibration BB into the block and measured 8.1 cm of penetration.  10% ballistics gel density calibrates at 8.3 to 9.5 cm of penetration so this block was slightly on the hard side of 10% ballistics gel specifications. Alternately, the BB came in just short of 3.25" which is the bottom of the 3.25" to 3.75" calibration range.
 
I shot the block at the range and then brought it home and recovered the bullets.  Immediately prior to the terminal test, I shot a five shot velocity test string from 8 feet over a Competition Electronic ProChrono Digital chronograph.

Typically, I'll display the recovered bullet along with all the data points I captured during the test, but I'm changing things up a bit with this test because I'd like to show you how powerful this new test media is going to be for me.  I know this will end up being long and picture heavy, but I hope you find this as interesting as I did.

I'll start at the front of the block.  These two pictures show the entry wounds of the short barrel and standard shots.  The black residue around the standard Gold Dot entry appears to be deposits of unburned powder.  The short barrel entry does not have powder deposits.  Could this be an indicator of the low flash propellents used in the GD Short Barrel load?  Also note the stretch lines radiating from the center bullet path.  While the two pictures are not perfectly scaled in size, the short barrel lines appear much longer.  Did this indicate the short barrel bullet expanded to a greater diameter?
 A side view of the expansion cavities revealed a bit more data.  In the back you see the short barrel bullet track.  The stretch lines mentioned above are now seen from the side view and they appear to be more pronounced (bigger) for the short barrel bullet than the standard bullet which is the bullet track in the front.  Also notice the lead fragments deposited in the bullet track of the standard bullet just above the word "copyright".  There is very little evidence of any lead fragments in the short barrel bullet track.  Is this discovery an indicator that the short barrel bullet retained more of it's original weight than the standard gold dot bullet?

And finally we have a picture of both complete bullet tracks.  The short barrel penetrated less than the standard and turned 90 degrees to the left and angled slightly up when finally coming to rest.  The standard Gold Dot turned down about 45 degrees at the end of travel and penetrated deeper into the block.

I was able to grab two still frames from the high speed camera during the "moment of truth" when the lead and copper met the gel.  Based on the similarities in the length of the expansion cavities, I have to believe these images represent similar moments in time for both rounds.  The GD short barrel bullet in the top picture shows a much larger and more dramatic/dynamic entry and volume displacement than the standard GD shown in the second picture.  I found the difference to be very substantial.  Is this another indicator that the short barrel bullet expanded more than the standard version?

I decided to test my theories and pulled the bullets out of the block.  All the captured data on the two recovered bullets and pre-test data are shown in the data sheet below.  In this specific test, the Gold Dot Short Barrel bullet did indeed expand more than the standard version and retained a greater weight.  

Since this was the first test with the new Clear Ballistics Gel media, I invited the Clear Ballistics Team up to the range to work the test with me.  The video below captures the entire test from the range.  Due to the clear nature of the gel, I no longer have make a second at home video portion for the bullet recovery.  I can now display the information that is typically covered in that portion of the test with still images in much better resolution.  I hope you enjoy the change and share my enthusiasm for the introduction of the new test media.

My Thoughts
In this specific bare gel test, it's clear to me that the Gold Dot Short Barrel performed better than the standard Gold Dot from the 3.1" long test barrel.  Both test shots were within +or- 10 feet per second of their 5 shot velocity averages so I felt good that the test shots fairly represented both tested loads.

I couldn't be more pleased with the Clear Ballistics Gel we used for this test.  It really lived up to the high expectations I had for it and it was incredible to see everything I had been missing in my previous tests.  For those that have seen both the SIM-TEST and Clear Ballistics media used in my tests, I welcome any comments on improving the testing with the new media. 
  

Disclaimer....This test should not be considered an endorsement or recommendation for the product(s) tested. It is up to each individual to make their own personal decision about 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 should not be used in any firearm unless the firearm manufacturer specifically states you are permitted to do so. 

13 comments:

  1. Super test

    The SB had a "bigger" cavity but was also shot second. The assumption is the shots are independent but why does the first cavity not cause some disruption in the gel area of the second entry allowing for a "perceived" bigger cavity? Also the second shot penetrated less. From data on bodies I have read penetration of a vital organ is the key thing needed for fatality. Why then is the shorter penetration "better"? Neither round over penetrated so that is not an issue.

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  2. Wow, Bruce. That clear gel and your high-speed camera sure add a lot to your testing! Super test! The 230-gr Gold Dots are visually different... something you really can't see in the smaller 9mm. The cavities on the .45 acp are shallower and wider at the bottom. I use the SB when available in the weight I use... 124-gr in 9mm and 230-gr in .45. So far there's none for the .380 and I chose the 165-gr regular SD for .40. The barrel length of your test pistol is about the same for the Kahr PM9/CM9, so the results should be similar.

    When I was "flash-testing" .40 S&W defense ammo for my Mag-na-ported Kahr P40 at the range, the only real lower flash I noticed was the Winchester PDX1 in 165-grain. Lower flash is relative, but the PDX1 was closest to zero flash.

    Thanks for a great test.

    Wynn, AKA wyntrout on KahrTalk.com

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    1. Thanks Wynn. Glad you enjoyed the test. This new media is some fun stuff to work with.

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  3. I was speaking about the difference between the regular Gold Dots and the Short Barrel version. I just noticed I forgot to include that.

    Wynn

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  4. Great test. It would be interesting to see the results of the SB ammo in a 4" or longer barrel. I like your work. You don't see much testing out there with the commonly carried concealed pistols in 3" barrels.

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    1. Thanks for the comment and the lack of data is what inspired me to start doing my own tests. I would rather know about 3" performance than "guesstimate" based on manufacturer published data for 4.5" and 5" pistols.

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  5. Where's the denim? Bad guys don't usually run around naked! As far as I'm concerned a plain gel test means little. You need to cover it with denim or some type of clothing to get more real world results. Shooting pure gel is similar to shooting water jugs that are lined up.

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  6. Bad guys don't wear denim jackets anymore. Denim test shows someone shot in the legs or someone shot with poor taste of clothing. But seriously no denim does not discredit this test. Shooting a block of gel isnt "real world," it's simulated just like intended.

    Thanks for the test. I've always wondered if SB ammo was functional or just good marketing.

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    1. So far in all that I've tested, it appears to be quite functional. I just wish it was easier to find. Ammo shortage or not, finding it has been a challenge.

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  7. I enjoy all you testing, keep it going. Can you do this test with a 3" .40 pistol, using the regular 180gr GD vs the 180gr SB GD? I would like to see some clothing added as it make it a worst case scenario instead of best case, which bare gel is to me. Thanks!

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    1. Hi Rick. Thanks for the positive comments. I have not seen Short Barrel GD 40 S&W available in literally years. It's been out of stock / no back order at all my usual ammunition suppliers.

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  8. I shot a burglar with 124+p through a steel table leg hitting the guy in the shoulder he ran off screaming they found the genius the next day because he dropped his wallet. He refused medical attention at first he but the made him go he lost his arm. All the officers and the Detective we're in shock everyone one wanted to know what ammo i was using it was the talk of the police station the Detective told me when i went to pickup my gun i told him he said every officer said there buying a box. Side not the table was from the 50's not that cheap crap they make today. I was 24 that day i can tell you i will never carry another ammo. My pistol was a Beretta 92 Border Marshall 9mm

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  9. Thank you very much for this test. Just exactly what I was looking for. Slightly less penetration because of the faster expansion. The Temporary cavity captured with your high speed camera really tells a story. The outside of the gel is bulged out. Thanks again for doing this good work to benefit anyone that takes the time to see it.

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