Test Gun: Colt 1911.
Barrel length: 5 inches.
Ammunition: Underwood .45 ACP +P and .45 Super 255gr Hard Cast.
Test media: 10% Clear Ballistics Gel.
Distance: 10 feet.
Chronograph: Caldwell Ballistic Precision Chronograph G2.
Five shot velocity average: 891, 1078fps
Gel Temperature 70 degrees.
The second installment of the Underwood hard cast woods load we take a look at the .45 ACP+P and the .45 Super. Both of these loads use the same 255gr hard cast Hi-Tek coated bullet.
I got a five shot average velocity of 891fps with a high of 902fps and low 888fps. Underwood lists their velocity of 925fps for this load.
With the .45 Super load, I got an average velocity of 1078fps with a high of 1082fps and a low of 1073fps. The advertised velocity from Underwood for this load is 1075fps.
I used the same pistol with both of these loads even though the pistol is not set up for the Super round. I did have one failure to feed.
The .45 ACP didn’t show any sign of excessive pressure even though it’s listed as +P. The .45 Super, on the other hand, flatted primers and primer flow into the firing pin hole.
Starting with the +P loading the first round had a velocity of 873fps and penetrated to 53.5 inches. The recovered weight was 247.8 grains. The second round hit the gel block at a velocity of 895fps and penetrated to 50 inches. It’s recovered weight was 247.6 grains.
The first round through the sheet metal had a velocity of 906fps and penetrated to 21.25 inches. It’s recovered weight was 247.6 grains. Round two had a velocity of 920fps and penetrated to 18.75 inches. The recovered weight of the second round was 249.3 grains.
With the Super load, the first round in the bare gel had a velocity of 1072fps and passed completely through all four gel blocks and was not recovered. I really didn’t expect that much penetration so I didn’t put a piece of body armor behind it. Learning from the first shot, I put the armor behind the last block and shot another round into the bare gel. It also passed through but bounced off the body armor and was found on the floor next to me. It’s velocity was 1075fps and the recovered weight was 251.3 grains.
Through the angled sheet metal the first round had a velocity of 1059fps and penetrated to 28.5 inches. The recovered weight was 242.8 grains. The second round passed through the sheet metal at a velocity of 1061fps and exited the side of the block at the 24 inches mark.
These loads exceeded my expectations by quite a bit. The .45 Super round is only the third round to pass completely through all 64 inches of gel. Sharing that title with the Underwood 147gr hard cast and the Double Tap 200gr FMJ 10mm.
The +P version was also the winner in the .45 ACP department with a max penetration of 53.5 inches, about 11 more inches then the next best, the Cutting Edge solid at just a little over 42 inches.