Underwood Xtreme Penetrators Clear Ballistics Gel.

Back in September of 2017, I posted about some testing I did with the Lehigh Defense Xtreme Penetrator in .45 ACP. I remember being surprised by the lack of penetration from a bullet with “Xtreme Penetrator” in its name.


Afterword I decided not to pursue that particular bullet any longer and tested some Double Tap hardcast ammo instead


It became clear that hardcast bullets completely out penetrated the Lehigh Xtreme bullets. On the various forums, I frequent some people suggested that the Xtreme bullet was designed to penetrate hard objects and would do better in after hitting bone and such.

What I came up with is some 20 gauge steel drawer dividers set at an angle of 30 degrees. With the understanding that steel and bone are not the same, I felt the idea had merit. To test the idea I shot one round of Double Tap’s 10mm 200gr FMJ and a round of the 200gr hardcast. The hardcast still passed through the two blocks of Clear Gel I had behind it. The 200gr FMJ on the other hand only went to 22 inches.

After posting this someone on one of the forums I posted about this offered to send me some Underwood Xtreme Penatrators to try out. He sent me four rounds each of 10mm, .45 Super, .45ACP, 9mm, and .40S&W. The person, that sent the ammo, asked if I try the .45 Super first. The test consisted of shooting two rounds in bare gel and then two through the 20 gauge sheet metal.

Starting off with the .45 Super, I shot four rounds through an HK 45C with a 4-inch barrel. The first round shot through bare gel had a velocity of 1111fps and penetrated to 23.5 inches. The second round was shot just below the first through the angled sheet metal and hit at a velocity of 1087fps and penetrated to 18.75 inches. The third round was shot in the upper right of the gel blocks and penetrated to 23.75 inches with a velocity of 1094fps. The last round was shot through the sheet metal just below the third and it had a velocity of 1105fps and penetrated to 20.75 inches.

None of the bullets shot through the sheet metal showed any directional deviation from the impact. The four rounds had an average velocity of 1099fps. This velocity is about 100fps less then what Underwood’s claiming of 1100fps and about 100fps more than my handload of this bullet I tested previously. However, even with the increased velocity the penetration only increased by three-quarters of an inch from 23 to 23.75 inches. This load is also a little on the flashy side. This bullet, at least in .45 caliber, still seems to suffer from lack of penetration depth even with the increased velocity. The sheet metal only slightly retarded penetration depth by about three or four inches.

About a month later I had a chance to try the 9mm 115gr loading. Just like the .45 Super, I shot two rounds in bare gel and two through 20 gauge sheet metal. The pistol I used was a Sig P229 with a 4.1-inch barrel. The first round in the bare gel had a velocity of 1210fps and penetrated 47 inches of gel before coming out the side of the third block and landing on the floor. The second round, fired through the sheet metal, had a velocity of 1190fps and penetrated 16.5 inches. Round number three shot into the bare gel hit at 1192fps and penetrated to 47.5 inches. Something interesting about this round, the bullet showed signs of tumbling, in the gel, at the 35-inch mark. The last round went through the sheet metal at a velocity of 1191fps and penetrated to 18 inches.

When comparing the 9mm to the .45 Super, the 9mm out penetrated the .45 by quite a bit in bare gel, 47.5 to 23.75. That’s almost twice as much. On the other hand, when shot through the sheet metal the 9mm lost a lot of its penetration. From a max of 47.5 to 18 inches, a loss of 29.5 inches. The .45 Super outperformed the 9mm but by only 2.75 inches when comparing the max penetration through sheet metal.

Unfortunately, when shooting the 10mm I had some issues and I was only able to catch two rounds in the gel, one through the sheet metal and one in bare. The other two exited out of the top of the first block. The first round through the sheet metal penetrated 21.25 inches. The velocity was not picked up. The second and third were shot, into the bare gel, both came out of the top of the block. I was able to pick up the velocity of the third round and it was 1482fps. I decided to shoot the last round into bare gel in hopes of getting at least one and it penetrated to 24.25 inches with a velocity of 1512fps.

As an aside, the wound tracks in the clear gel actually looked impressive, at least the ones fired in the bare gel. With the .45 and 9mm, the tracks didn’t look much different than a ball round and certainly not like what I have seen with hollow points. This 10mm load looked much more like what I would expect to see with an expanding bullet. I’m not sure if that means anything or not but I thought it was worth mentioning.

Lastly, I shot the .40 S&W Underwood 140gr through the gel using my Sig P229. Two rounds through the bare gel and two through the sheet metal. The two rounds through the bare gel I got 22.5 and 23 inches. The velocity was 1250fps for the first one and 1260fps for the second. Both bullets were recovered base forward. The first bullet appeared to have tumbled at the 7 and 18-inch mark. Rounds one and two through the sheet metal went to 17 and 18.5 inches. I only got velocity from the second bullet and it was 1252fps.

At this point, I don’t think I will shoot the .45 ACP +P. I just don’t see the point.

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