How to mod a KSC USP .45 to full auto

[Ghost Snake]

IMPORTANT UPDATE scroll down

Alright, I was planning on doing this "how to" once I got all my upgrades for the gun finished, but some members (namely swatt13) want the info now, so here goes. :-D

I've modded all of my GBB's to date to fire full auto. This includes TM DE .50AE, TM HiCapa 5.1, TK VP-70M and obviously, my KSC USP .45. And yes, I know what you are thinking, "how gay is a full auto Desert Eagle", and well, I agree. I only did it to see if I could, but now I wish I didn't because I had to butcher a part to do so, and I'm having a hell of a time trying to find a replacement part. But, if anybody actually wants a full auto DE, I'll sell it to you (if you're age verified of course).

Anyway, the USP was by far, and I mean by FAR, the easiest GBB I've modded, so dont think they are all this easy.

Ok, here are the before pics from the left and right side. The red box indicates the part that will be removed. All I did was I took a dremel and cut off the tab. Thats it. Easy peasy. Figuring out how to do it is the hard part though.

Before pic 1
Before pic 2

And here are the after pics. Sorry about the quality. It was really hard to get decent pics. My apartment has horrible lighting. If you have a USP, you'll know which part to cut though. There is only one "tab" on the right side.

After pic 1
After pic 2

And just so you know I'm not on an evil plan to ruin everyones USP, heres a video to show you it works :cheers:

Video

ROF looks to be easily over 10 RPS. And I am running propane on a stock slide FYI. But like I said, I didnt plan on doing this how-to until my upgrades were done, but whatever. Happy modding.

[Lakonian]

wouldn't that cause extreme amounts of wear? tell me if you see anything unatural, otherwise I'd like to try that

[swatt13]

much appreciated gs! ill try it out once i get me usp fixed (stupid chamber block isnt holding my hop up in properly (cant pi it in place))

[Ghost Snake]

Originally Posted by kos

wouldn't that cause extreme amounts of wear? tell me if you see anything unatural, otherwise I'd like to try that

I see no reason why it would. Nothing in the firing cycle is changing. Whether you shoot it in semi or FA, the wear will be the same shot for shot. However, being full auto, you can get a lot more shots off in the same amount of time.

[Gcoap]

I had my Eagle destroy its self, what part do you need i might be able to get it to ya?

[Ghost Snake]

Originally Posted by Gcoap

I had my Eagle destroy its self, what part do you need i might be able to get it to ya?

If you have the manual, it is part # 50AE-47. If not, if you take off the slide, it is the black rectangle thing that is connected to the trigger and releases the hammer.

[MadMax]

Hmm, chopping down the trigger disconnector.

You don't find that you get light strikes with propane on warm days? Usually the hammer needs to be held back until the slide cycles fully forward before you can let it back down to open the mag valve. If the hammer fails to lock and just follows the slide forward, you can get a light strike misfire.

[Ghost Snake]

Originally Posted by MadMax

Hmm, chopping down the trigger disconnector.

You don't find that you get light strikes with propane on warm days? Usually the hammer needs to be held back until the slide cycles fully forward before you can let it back down to open the mag valve. If the hammer fails to lock and just follows the slide forward, you can get a light strike misfire.

I have never had that problem. But you are right, technically the hammer is striking with less force. I have been running this setup for sometime and have never had a missfire, or anything close for that matter. I'm sure there is a minor fps loss after the first shot, but probably negligible. A stronger recoil and hammer spring would lessen the fps loss, but I really dont think it is losing much. Maybe I'll take it outside and really make an effort to see how much further the 2nd, 3rd etc. shots go, compared to the first shot. Not that it matters to me though, cause I'm just using this for CQB. Even when used outdoors, I dont see how the fps loss would be a problem, as long as it is reliable, which it has been.

[manchovie]

chrony it

[Ghost Snake]

Originally Posted by manchovie

chrony it

Not sure how that would work. I dont think my chrono can keep up with 10+ rounds per second. But I wouldnt know, I have never tried anything other than semi. I guess if I drain a whole mag it will pick up the first one and hopefully a few after that. But then cool down would probably be effecting it a lot though. What I really need is some way to clock the second shot. Whatever. I'll try it anyway, just as soon as I feel motivated enough :cheers:

[MadMax]

It doesn't work on the TM Hicapa I tried. Not having a working disconnector allows the hammer to latch into a surface in the underside of the recoil block which locks the slide back with every shot.

[Ghost Snake]

UPDATE

Today is a particularly hot day, about 27 degrees, and I experienced my first malfunctions with propane. My previous use was indoor at about 20 degrees, in which I never had a problem. But after leaving the mags out in the sun today, I had a number of "light strike" misfires. Unfortunately I am out of duster, so I cant test that, but I dont think duster would be a problem due to the lower pressure. A stronger recoil and hammer spring, and maybe even a high flow valve should cure this, but I cant say with certainty. But for now, I would suggest that nobody try this mod. As soon as I get my upgrade parts (I'm waiting on you MadMax/Hojo, check your email :cheers: ), I'll inform everyone as to how it goes. Also, as soon as I get some more duster, I'll give an update on how that goes as well. If you still feel the need to try this, be warned that it will not work properly on propane in hot temperatures if the gun is stock.