Not long ago I picked up a G20 and I thought I'd post of some of the ballistics and observations from testing a few Underwood loads.
The three rounds I tested were the 200gr Hard Cast Lead Flat Nose, 140gr XP (this is the Lehigh Defense Xtreme Penetrator bullet), and 180gr Gold Dot.
The 200gr HCFN and the 140gr XP were intended for woods defense, while I got the 180gr Gold Dot with home defense in mind. (Don't mind the Corbon DPX which are second from the left).
140gr XP
If you don't know about the Xtreme Penetrator, it's a solid copper bullet that's basically a flat nose FMJ profile with four flutes cut out to force hydraulic tissue outward to create more damage. Underwood advertises it at 1470fps from the G20's stock barrel. I came in rather higher at 1537fps on average. That means this load is good for a silly 734ft.lbs. from a semi-auto that holds 15+1 rounds. This also comes out to a Power Factor of 215. Compare that to typical .45ACP at 200 and recoil isn't anything crazy in the G20.
I don't have a good picture of the gel blocks I hit with this, but I shot three rounds into gel and they ranged from 24.5-27" of penetration with "wound tracks" that look akin to a good 9mm hollow point. Here's a picture of the three recovered bullets.
200gr HCFN
I picked up the 200gr load because I sort of felt like the 140gr XP was a bit light on penetration for bear or moose. Underwood's site says these are good for 1250fps, but doesn't list barrel lengths so I think 1200fps from the G20's barrel is probably what they're estimating. I got 1154fps on average which is good power but a bit disappointing after coming in over the mark with the XP. Still, this is good for nearly 600lb.ft. with a PF of 230, so recoil is still manageable and obviously when penetration is the goal weight can be more important than energy.
Penetration with this load was... interesting. I put two blocks end to end (32" total) and the image below tells most of the story. All three rounds zipped straight through. After the first two, I asked my friend to spot downrange to see if he could see where the third round hits the ground (figuring it would be arcing downward after exiting, and would hit the ground around 75 yards downrange). Nope. He saw the impact and it was 6ft up the berm at 100 yards, straight in line with my point of aim. Basically the round zipped through the block and still had enough velocity to make it to the berm and it hit with authority.
If I had to take a guess, these would exceed 4ft of penetration. Good for hitting the vitals in a bear or moose, and good for getting through bone along the way. The "wound track" was unimpressive so bleeding would be minimal if you miss the vitals. I think part of the drawback to this round is that the bullet profile is somewhat rounded where the shoulders of the bullet meet the meplat. It would be better if it had sharp shoulders for more damage and less penetration.
Bottom line I think this is a bit too much penetration, but at least I can confidently say it'll punch through if I hit bone or have to shoot a wild animal from a weird angle.
180gr Gold Dot
tnoutdoors9 reviewed this load on YouTube and his results looked similar to mine. This load is the same 180gr Gold Dot bullet found in Speer's 40S&W factory load, but here it's loaded atop a 10mm shell and advertized to 1300fps from a G20 barrel. I clocked it at 1268fps on average, meaning it's good for 642ft.lbs. with a PF of 228 (again the recoil is stout but not absurd). What was absurd was what these did in ballistic gel...
I fired 7 of these into gel to get a real good sense of if it performs consistently. By and large, it does, which is impressive when you're over-driving a bullet by this much. For reference the factory 40S&W speed for this bullet is 985fps, so this is going nearly 30% faster than designed, carrying 66% more energy.
Penetration ranged from 12.75" and 13.5" through heavy denim, up to a high of 17" into bare gel. All rounds fell within the FBI specified range for two-legged defense. The average penetration was 15.1" (which is perfect).
5 of the 7 tested rounds retained all their weight to the end of their travel, while the other 2 each shed one pedal for a weight retention of 90.5%. The real story is what the bullets look like afterward. I'm sure if these were anything other than Gold Dot construction, they would have completely come apart. What's nice about Gold Dots is that they're not only bonded (which isn't enough when you over-drive a bullet by this much) but they have that copper post in the center of the core that stops jacket core separation. These tried it, but stayed together and clearly weren't in much danger of coming totally apart. At worst these will shed a pedal or two, especially if a round hit bone or something. The two denim shots looked the most like a God Dot should, with the denim plug seemingly protecting the bullet's face from the full hydraulic pressure of the gel. The 5 bare gel shots basically turned inside out, and the result is nasty, of the 'holy crap I don't want to get hit with it' variety.
Here are the recovered rounds, positioned in various orientations to give you the best idea.
Here's the gel block. Don't mind the two rounds that look like they only went about 8". Those had "wound tracks" running out near the end of the block and these experienced bounce back. This is basically a known phenomenon seen with Clear Ballistics blocks. It tends to happen more with high power rounds like these, that make huge temporary cavities. Speaking of "wound tracks" these would cause serious damage to tissue out to 9"+.
Bottom line with the 180gr load is that it's nasty and very impressive. If you told me "you're going to have to shoot to defend your life in 5 minutes and you can have a handgun of your choice with any round", I'd take a G20 with these. There are more powerful options out there, but with lower capacity and more recoil. This seems like the most devastating thing out there in a high capacity, semi-auto handgun platform.
To sum up regarding the 200gr and 140gr loads, I ended up deciding to load them alternating in my 'woods magazine'. I figure that way I get the best of both worlds with more tissue damage from the 140gr and more penetration from the 200gr. When I start hand loading I plan to try some hard cast 200gr loads with sharper shoulders to hopefully narrow down to one round that performs in between both.
As far as Underwood is concerned in general, I'm totally sold on their ammo. I like how hot they've been able to load these, and from everything I've seen they typically meet their advertised performance numbers. It's worth mentioning I also picked up some of their 180gr FMJ, which were very accurate and very much full power for well under $1 a round. Underwood will be my choice for high power defense and plinking loads going forward.
The three rounds I tested were the 200gr Hard Cast Lead Flat Nose, 140gr XP (this is the Lehigh Defense Xtreme Penetrator bullet), and 180gr Gold Dot.
The 200gr HCFN and the 140gr XP were intended for woods defense, while I got the 180gr Gold Dot with home defense in mind. (Don't mind the Corbon DPX which are second from the left).
140gr XP
If you don't know about the Xtreme Penetrator, it's a solid copper bullet that's basically a flat nose FMJ profile with four flutes cut out to force hydraulic tissue outward to create more damage. Underwood advertises it at 1470fps from the G20's stock barrel. I came in rather higher at 1537fps on average. That means this load is good for a silly 734ft.lbs. from a semi-auto that holds 15+1 rounds. This also comes out to a Power Factor of 215. Compare that to typical .45ACP at 200 and recoil isn't anything crazy in the G20.
I don't have a good picture of the gel blocks I hit with this, but I shot three rounds into gel and they ranged from 24.5-27" of penetration with "wound tracks" that look akin to a good 9mm hollow point. Here's a picture of the three recovered bullets.
200gr HCFN
I picked up the 200gr load because I sort of felt like the 140gr XP was a bit light on penetration for bear or moose. Underwood's site says these are good for 1250fps, but doesn't list barrel lengths so I think 1200fps from the G20's barrel is probably what they're estimating. I got 1154fps on average which is good power but a bit disappointing after coming in over the mark with the XP. Still, this is good for nearly 600lb.ft. with a PF of 230, so recoil is still manageable and obviously when penetration is the goal weight can be more important than energy.
Penetration with this load was... interesting. I put two blocks end to end (32" total) and the image below tells most of the story. All three rounds zipped straight through. After the first two, I asked my friend to spot downrange to see if he could see where the third round hits the ground (figuring it would be arcing downward after exiting, and would hit the ground around 75 yards downrange). Nope. He saw the impact and it was 6ft up the berm at 100 yards, straight in line with my point of aim. Basically the round zipped through the block and still had enough velocity to make it to the berm and it hit with authority.
If I had to take a guess, these would exceed 4ft of penetration. Good for hitting the vitals in a bear or moose, and good for getting through bone along the way. The "wound track" was unimpressive so bleeding would be minimal if you miss the vitals. I think part of the drawback to this round is that the bullet profile is somewhat rounded where the shoulders of the bullet meet the meplat. It would be better if it had sharp shoulders for more damage and less penetration.
Bottom line I think this is a bit too much penetration, but at least I can confidently say it'll punch through if I hit bone or have to shoot a wild animal from a weird angle.
180gr Gold Dot
tnoutdoors9 reviewed this load on YouTube and his results looked similar to mine. This load is the same 180gr Gold Dot bullet found in Speer's 40S&W factory load, but here it's loaded atop a 10mm shell and advertized to 1300fps from a G20 barrel. I clocked it at 1268fps on average, meaning it's good for 642ft.lbs. with a PF of 228 (again the recoil is stout but not absurd). What was absurd was what these did in ballistic gel...
I fired 7 of these into gel to get a real good sense of if it performs consistently. By and large, it does, which is impressive when you're over-driving a bullet by this much. For reference the factory 40S&W speed for this bullet is 985fps, so this is going nearly 30% faster than designed, carrying 66% more energy.
Penetration ranged from 12.75" and 13.5" through heavy denim, up to a high of 17" into bare gel. All rounds fell within the FBI specified range for two-legged defense. The average penetration was 15.1" (which is perfect).
5 of the 7 tested rounds retained all their weight to the end of their travel, while the other 2 each shed one pedal for a weight retention of 90.5%. The real story is what the bullets look like afterward. I'm sure if these were anything other than Gold Dot construction, they would have completely come apart. What's nice about Gold Dots is that they're not only bonded (which isn't enough when you over-drive a bullet by this much) but they have that copper post in the center of the core that stops jacket core separation. These tried it, but stayed together and clearly weren't in much danger of coming totally apart. At worst these will shed a pedal or two, especially if a round hit bone or something. The two denim shots looked the most like a God Dot should, with the denim plug seemingly protecting the bullet's face from the full hydraulic pressure of the gel. The 5 bare gel shots basically turned inside out, and the result is nasty, of the 'holy crap I don't want to get hit with it' variety.
Here are the recovered rounds, positioned in various orientations to give you the best idea.
Here's the gel block. Don't mind the two rounds that look like they only went about 8". Those had "wound tracks" running out near the end of the block and these experienced bounce back. This is basically a known phenomenon seen with Clear Ballistics blocks. It tends to happen more with high power rounds like these, that make huge temporary cavities. Speaking of "wound tracks" these would cause serious damage to tissue out to 9"+.
Bottom line with the 180gr load is that it's nasty and very impressive. If you told me "you're going to have to shoot to defend your life in 5 minutes and you can have a handgun of your choice with any round", I'd take a G20 with these. There are more powerful options out there, but with lower capacity and more recoil. This seems like the most devastating thing out there in a high capacity, semi-auto handgun platform.
To sum up regarding the 200gr and 140gr loads, I ended up deciding to load them alternating in my 'woods magazine'. I figure that way I get the best of both worlds with more tissue damage from the 140gr and more penetration from the 200gr. When I start hand loading I plan to try some hard cast 200gr loads with sharper shoulders to hopefully narrow down to one round that performs in between both.
As far as Underwood is concerned in general, I'm totally sold on their ammo. I like how hot they've been able to load these, and from everything I've seen they typically meet their advertised performance numbers. It's worth mentioning I also picked up some of their 180gr FMJ, which were very accurate and very much full power for well under $1 a round. Underwood will be my choice for high power defense and plinking loads going forward.
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