I've gone and done it! I've shot a friend's Mark23 before but now I finally got one of my own. I've read countless posts about Mark23 vs. Tactical threads here but there hasn't been any visual clues as to how they're different. I can tell you that Mark23 is not just a larger Tactical. The Tactical is an enhanced USP as it shares the same frame, slide and internals as standard USP, but the Mark23 is an entirely different beast. I didn't appreciate it before but now that I've joined the Mark23 owner's rank, I have to say it's the ultimate combat pistol.
It is big, that's for sure! I don't have my Desert Eagle here right now to compare against so it's just Mark23 vs. Tactical. The size difference is immediate. Actually, for its size Mark23 is fairly light. It weights just about a steel 1911 and it's fairly balanced in terms of weight distribution and center of gravity. This is further enhanced by a fully loaded magazine.
I never figured out why Tactical sights appeared taller than Mark23 sights, since both are designed for suppressor cans. Now you can see why. The Mark23 has a step up built into the slide's front/rear sight bases, therefore the actual sights don't have to be as tall. Also its' obvious that the Mark23 is more than length vs. Tactical. It's also beefier in terms of slide and frame. The front of frame has the open ended slotting for HK rail. In USP and Tactical they're closed.
Another comparison of sizes. The trigger guard and grip are both thicker on the Mark23. That's the main reason that Mark23 feels less ergonomic vs. 45 Tactical. In an earlier post, the Mark23 grip was measured as 6" circumference, while the 45 Tactical has 5.75" circumference. I found that both are perfectly fine in single-action trigger reach, but DA trigger on Mark23 requires abit more extension of my trigger finger. Bottomline is that DA is not bad with a 2 handed grip, but shooting DA one handed wont be my first choice.
This is a look at line of sight. Mark23 is geared toward combat type shooters, where as Tactical is specialized for bullseye shooting with its adjustable and notched rear sight. Also is another look at the width of the grip. The back serration is more extensive vs. Tactical. Both the slide and frame on Mark23 are also thicker.
Visual comparison of slide and recoil springs. The key to Mark23's ability to take 30000rd of +P ammo is the combination of slide, frame and recoil spring. The slide appears to be much more massive vs. Tactical. That's why even though Mark23 is shorter than USP 45 Elite, it still outweights it. The same size increase can be said of the recoil spring. Not only is Mark23 recoil system longer, the springs are also wider. The Mark23's outer springs are nearly 30% thicker than USP, and the thicker inner buffer springs are about 50% thicker than USP. The wider spring coils also becomes the culprit in causing scratches barrel bottom's finish.
Here's a look at the frame differences. Once again the Mark23 is built for ultra durability. There are more and larger steel inserts in the polymer frame to support the bigger slide. The Tactical has the standard USP type steel insert stubs which now appear really small. The Mark23 has bigger steel support areas in contact with slide, usually more than twice as large in terms of surface contact.
The final word is that Mark23 is one seriously designed combat handgun. I wouldn't doubt for a minute that it was the winner in SOCOM competition. The Tactical however is not slouch, and is the more ergonomic of the two. If the current US Army tests do not require SOCOM's 30000 +P rating, the Tactical should more than suffice as the new combat pistol. Is the Mark23 twice the gun that USP45 Tactial is? I dont' know, everyone's value system is different. I can say however that the Mark23 is the ultimate HK pistol!