PERMA-GEL Room Temperature Ballistic Gel!
Dr. Darryl Amick the inventor that brought us Hevi-shot is the creator of PERMA-GEL. Tired of the expense and onerous task that normal ballistic gelatin posed for testing his new projectiles he decided to do something about it. Dr. Darryl sent me a test sample to try. The two blocks measured 5 1/2" x 5 1/2" x 16" long and weighed 15 pounds each. I finally got a break in the weather and headed out to the range. Some of the results surprised me.

<click on pictures for larger view>
The range is flooded so I found a secluded spot; the down side was I could only shoot 25 yards. While representative of bullet performance, I’m sure you are all aware that this distance is a very rough ride for a bullet. Penetration is reduced due to violent expansion caused by the bullet hitting at such high velocities. Longer ranges should show greater penetration and more controlled expansion, but hey, if the bullets can survive this they can sure as heck survive the 100 yard test.

I shot the medium 6 times - twice each with these loads:

            .50 cal Omega              250 grain SST  150 grains Pyrodex Pellets        MV 2250 FPS

            .375 H&H Encore        220 grain Hornady Interlock                             MV 2852 FPS

            .300 WM Encore         165 grain SST                                                  MV 3265 FPS

L-R

250SST, 220 .375, 165 30 cal

Check out how high the 15 lb block springs in the air!

I shot a 250 SST first and was surprised to see the lead 15 pound block of gel catapult nearly 2 feet into the air. Amazingly the bullet penetrated 24 inches and expanded to .733 retaining 179 grains (71%) of weight. The .375 H&H was next, I was extremely surprised to see it penetrated less distance than the ML bullet only 19 ¼”. Expansion was terrific at .79” and weight retention was 130 grains (59%). The 300 win mag was last and the most entertaining. Impact was cataclysmic; the ¾” x16” plywood support base was crushed by the violent force of gel expansion.  The jacket expanded to .7” and was the only part of the bullet that made it to the second block - a total of 17”.
Perma Gel Video Streams Click each to view (Windows Media Player)
PERMA GEL shot with 250 grain SST from an Omega WOW! 300 Mag makes the block jump!

 

250 SST

 

Close up of 250 SST

 

250 SST and 220 .375 H&H behind it.

I’m sure as you look at the attached pictures you’ll notice a couple of things. First in each case the jacket of the bullet made the greatest distance whether it had any lead attached to it or not. I'm guessing that this is due to the cutting action of the sharp fragments slicing through the gel as compared to round bodies crushing through.

 

First block

 
Study of the first block of gel showed that all bullet expansion took place after the first 1 inch and was complete by about 8 inches and even in here at the largest permanent wound channel the shed bits of jacket shrapnel traveled the furthest from the bullet path. After about 8 inches, the wound channels (bullet paths) all coned down to the bullet diameter or less. The bullets aspect at rest showed them to have been tumbling at this point and I surmise the tumbling started at the point where expansion stopped – at about 8” into the bullets path. Really raises the question of the value of bullet expansion doesn't it? The two shots fired with the 300 were awesome to behold and even more remarkable when I review the video tape of the test. There has been a lot of talk about the existence of hydrostatic shock and the value of bullet performance measurements like FPE, TKO et al and many good arguments are made for and against each. Which system is right I do not know but I will tell you this. Anyone who believes that there is no shock factor or energy dispersion involved in high speed bullet impacts is very mistaken. The first shot with the 300 crushed the plywood directly below the mass expansion point, the second shot I placed the blocks end for end on a 2x6 saw horse, the expansion of the gel was so violent that the 2x6 was broken under the lead block! Most have you have seen the video of the mule deer I shot in the neck last fall, you’ve witnessed the way his neck almost doubles in size by the force of the bullet impact. When that kind of energy transfer can destroy the substrate it is sitting on, no one will make me believe that energy transfer has no effect on the killing of game. The 300 penetrated the least distance, perhaps because of a less rugged bullet design but the visible destruction it unleashed was awesome to behold.

 

Top of 2x6 Sawhorse

 

Bottom of Sawhorse
6 shots was about all I could get into the blocks before I started to worry that the results would be skewed by previous disruptions. The clear media is fantastic for observation of the bullet path and wound channel. While the argument is made that gel does not have bones the tests are good for the consistent media resistance on all the projectiles shot, allowing for comparative results and study. Even though I was at the upper end of the temperature range for performance (75 F) the gel I believe has as much if not more bullet resistance than flesh does. PERMA-GEL does meet the FBI Ballistic Gelatin Standard of 2.95”-3.74” of penetration by a steel BB @600 fps when used at 55 – 75 degrees F. Without a doubt PERMA-GEL far out performs any sand, compacted dirt, wet newspaper tests I've done for ease of use and consistency. The best part is the gel is cooling as I type this for another trip to the range. Totally recyclable a few hours cooking at 225 F reliquefies the material and if you shove the blocks into an old pair of panty hose before heating you can strain and remove all bullet fragments. All in all the principal lesson I learned while shooting PERMA-GEL is that I need to shoot it a lot more!
PERMA-GEL should be available for retail very soon from D-Squared-A, Dr. Darryl's engineering company. You can reach him @ 541 926 2885
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July 31, 2005 Update
   
Today I got out for a little range session. I was busy checking out new loads for my 300 Win Mag, 375 H&H and setting up 2 new Encore barrels; a 270 Win and a 209x 50.

I remain extremely impressed with the accuracy of the 165 Grain SST in my 300 mag but concerned at how it comes apart in the medium. Today I shot Barnes XLC, Trophy Bonded Bear Claws and Hornady Interbonds all in 165 grain weights. All bullets shot to pretty much the same point of aim at 25 yards so one after another I gave them a ride into the PERMA-GEL.  Once again the incredible shockwave created in the gel during energy transfer was awe inspiring. I'd built a base for the gel based on the previous experience out of a 4x4 and two layers of 2x8 on top. This was so much toothpicks by the time I was done shooting. There is no doubt in my mind energy transfer or hydrostatic shock occurs and plays a big role in the effectiveness of a cartridge.

 .300 WM Encore         165 grain Interbond                                         MV 3021 FPS

 .300 WM Encore         165 grain Barnes XLC                                     MV 3198 FPS

 .300 WM Encore         165 grain Trophy Bonded Bear Claw               MV 2895 FPS

  .270 WM Encore         130grain Interlock                                           MV 2780 FPS

            .375 H&H Encore        270 grain Hornady Interlock                             MV 2748 FPS

            .50 cal Encore             240 grain Dead Center 150 gr Pyrodex Pellets   MV 2120 FPS

  .50 cal Encore              180 grain "The Bullet" 150 gr Pyrodex Pellets    MV 2250 FPS

The bullets from L to R:
.50 cal 240 DC, .50 cal 180 "The Bullet", 30 cal 165 Interbond, 30 cal 165 TBBC, Petals of 30 cal 165 XLC, .270 cal 130 Interlock.

First the 300 win mag results.
The Barnes XLC penetrated completely through 35 inches of the gel leaving only two of the petals inside at about 23". Incredible penetration, but surprising results with the petals pealing off without striking bone. The XLC like all the bullets tested was tumbling after initial expansion.

Hornady Interbond. Penetrated 23.5" expanded to .708" and retained 185 grains (89.7%)

Trophy Bonded Bear Claw. Penetrated 25" expanded to .755" and retained 158 grains (95.8%)

All bullets in this test tumbled after expansion. If massive penetration is your thing then you simply can't touch the Barnes bullet, my test bullets may still be going for all I know! Both the Interbond and the TBBC really impressed me. I got more than enough penetration to shoot sideways across an elk or moose and the bullets really held together. All things being equal as I can't find fault with any of these bullets price would be the deciding factor for me. Here the Hornady Interbond is far and away the best deal.

Bullet Prices: Interbond $40/100, XLC $48/50 and TBBC $42/25.

Left: measuring Interbond penetration
Right TCCB penetration
.375 H&H 270 Grain Interlock
After pulling the trigger on this bad boy all I can say is WOW!!! For the first time in my life I was glad I had a specialty recoil pad on a rifle. Unleashing this caliber with the big bullets gives you a whole new respect and understanding of what a dangerous game gun is all about. The 35" of gel barely slowed the big bullet down and we watched dumb founded as the bullet stuck the 100 yard berm with a grenade like explosion. I've always shot my 375 with 210 Barnes X or 220 Interlocks, the heavy bullets are something else. Both 15 pound gel blocks launched into the air in fine style befitting a Die Hard movie. I seriously recommend the Sims Anti Vibration Laboratory Limbsaver pad!
270 Win 130 grain Interlock
Penetration was a fantastic 25", expansion to .562" and weight retained 87 grains (67%). Great performance for this very economical bullet. I'm curious if the great penetration came from the lower energy numbers produced by the lighter bullet. Does less energy transfer equal less expansion and greater penetration? The 130 grain 270 expanded 203%, the 165 Interbond 230% and the TBBC 245%.  It certainly isn't the differences in section density as the variance is .006 from high to low. Interesting, thought provoking results to say the least. 


130 grain 270 in gel. To the left you can see the Interbond from the 300 Win mag

  

The Muzzleloader bullets.
I chose two sabot clad bullets I've never shot an animal with for testing. The 240 Grain Dead Center and 180 grain "The Bullet" The DC is an all lead bullet with an identical shape to a Hornady SST including a polymer tip. "The Bullet" is probably the strangest projectile I've ever shot from a rifle, period. Metal jacketed this bullet has an 5/16" hole straight through the center from tip to base. The manufacturer Jada Enterprises claims this hole greatly improves the BC of the bullet putting centerfire ranges with in the grasp of ML shooters. That claim I don't have an answer for, today I was testing for penetration and bullet expansion.

240 DC. Penetration was an anemic 13 inches, expansion 1.12" and weight retained 205 grains (85%). While the expansion and weight retained were terrific performance I think the violent expansion played a big role in the poor penetration. In my mind the DC bullet was way out of it's league at these speeds, in fact it's entry hole into the gel shows great heat, burning the gel. Many bullets hit the gel at much greater speeds but the DC's are the only bullets to burn the gel. Perhaps a sub 1800 FPS impact speed would show better results for this bullet.

180 The Bullet. Penetration was a poor 15.5" expansion was .690inches with only the cladding left intact, weight retained 70 grains (39%) The Bullet too seemed like it would profit from a slower velocity. While it out performed the DC in penetration it just about completely shed all the lead in the bullet. Curiously the Bullet cut a "hole punch" hole into the Gel.

Neither of these ML bullets impressed me especially with the SST used in the first test as a benchmark. However there are yet the 100 yard tests to complete and the winner of those still remains a mystery.

 

This is the DC entrance hole. Melted in.

 The hole punch effect from The Bullet.