UTG MP5SD 5/6?

[Ranger Stubbs]

I like the HK MP5. Always have. A TM MP5A4 was my first AEG. With all the AEG's that have come out since the TM version of the RS guns years ago now, most people just roll their eyes at another MP5 on the skirmish field. But something made me go back to one recently, the low cost of the UTG line of products. After reading all the reviews ever posted to try and figure out if it would be worth even the lower cost of the gun, I was impressed enough to buy one. Yes, I have to go cheap and I'm picky.

 

Personally, I don't really like the looks of the A series front ends vs. the SD versions. This is for sentimental reasons, I carried the RS MP5SD3 in the 75th Ranger Regimental Headquarters RRD, or Ranger Reconassince Detachment in 1996-98. So the UTG MP5 left me wanting out of the box for an SD version. I went digging through some of my old, inoperable stuff for my CSI MP5 SD6, just to see if the front ends would switch out. The CSI LPEG was a purchase made before UTG released their AEG, a totally different animal. I ended up buying it on Ebay for under 30 dollars shipped. The CSI definitely wasnt skirmish worthy, let alone even worth shooting in my apartment, in my opinion. The gun is a true LPEG after all. I gave it to my seven year old son and even HE complained about the accuracy, velocity, and ROF compared to my other guns he's fired. Takes after his daddy! It did have some worthwhile features in the quality of the body, which looked pretty much like my old TM. Same with the UTG gun. Which made me wonder if this idea of mine would work, due to the similarity of both guns to the TM, both replicas of a replica.

 

After taking both front ends off the guns, I was happy to see the center struts were the exact same dimensions. Same with the outer cocking tube sizes. A few differences were present, the UTG has a full length metal tube running along the inside of the cocking tube. The CSI gun has a smaller inside diameter of the cocking tube from the use of thicker plastic, along with a corresponding smaller charging handle and rod. The UTG gun also has a longer collar at the front of the main body that the cocking tube slips into. Still will work though, but needs a few pretty simple modifications. The only tools needed are a large and small phillips screwdriver, hacksaw, and hobby knife.

 

The first thing to do is remove the front ends off of both guns. Take out all handguard pins and take the forearms off, exposing the battery compartments. The UTG's fuse box needs to be unclipped from the center support. The CSI's handguard support needs to have the left side removed to get at the screw in front of the hop up, nessasary for removal of the complete front end. More on that later. Detach the silencer can by twisting a half turn to the left and pulling it off the front of the gun. Then remove the four screws of the left handguard plate, two large screw/nut combinations on top, two very small screws at the bottom of each side of the battery opening. Gently separate and remove the left half.

 

Now we go back to the similarities noted before. Both guns have the same TM like method of pulling the front ends off. There is a screw/nut combination directly in front of the hop up unit, holding a metal clamp around the barrel. Remove this carefully, trying not to damage the threads. The cocking tube and front end can be slowly worked off of the guns at this point. The charging handles can be taken out by retracting the handles and unscrewing them from the front of the rod. Pull the metal extension tube from the UTG cocking tube as well. This will take a good yank to get it out.

 

OK, we now have both guns to the point where we can swap forends. Fitting is only a small pain in the @#$ at this point. First, using your hacksaw, cut the UTG metal cocking tube in half. That metal tube will NOT fit all the way into the CSI cocking tube! It doesnt have to be pretty, you wont see any modification after the gun is reassembled. Discard the front half of the tube, keep the rear half. The front collar of the UTG body needs to have about an eighth of an inch removed to dovetail with the CSI cocking tube. You can use a hacksaw for cut down and then your hobby knife to make final adjustments to get it flush. This does have to be done well or you will see a gap between the tube and the body on reassembly. Insert the UTG metal tube into the CSI cocking tube. This will take a good push to get it into the tube. Reinsert your spring, rod and charging handle.

 

Now we are ready for final reassembly. Tuck the wiring back through the rear of the SD forend. Slide the whole thing back until the center strut hits the metal barrel clamp. Make sure the inner barrel lines up with the hole in the front sight assembly then work everything back into place. Using the screw/nut combo, tighten the forend onto the main body. There should be no flex or wobble due to the metal tube inside creating ridgity. Reattach your suppressor can. I did do one thing to make a switch back to the A series forend even more simple if I ever wanted to. Instead of having to take the CSI left hand battery compartment off everytime to access the main screw/nut, I notched away the plastic that covers up the screw. It doesnt compromise the structural integrity of the gun. Very easy to access now, leaving you with A or SD series forends you can switch back and forth in less than five minutes.

 

One last simple mod done to the gun, the rear sight on the UTG gun just plain ###### me off. It's low quality is horrible, and I'd love to slap the hell out of whoever put that into the design! An easy fix though, as the CSI gun comes with the correct (and nice looking) diaopter sights. They're even metal! Simple to change too, just unscrew both sights from both guns, swap them and rescrew them down. Easy to do and it makes the UTG look and point a hell of a lot better.

 

I gained a few advantages with combining guns. I now have an MP5 that I can configure into four separate models, switching stocks or forends, converting to any form I want the weapon to be in less than ten minutes. The CSI front end added the weight that left the UTG a little too light to begin with. The CSI silencer also has the actual holes drilled in the can and is filled with foam for an actual working suppressor. It didnt make a noticable difference when firing the CSI version because not enough air was being pushed out of the barrel, that gun only chronoed at 135fps anyway. When its on the UTG, it definitely makes a noticeable difference. Over twice the amount of air is coming out of the muzzle of the inner barrel. The can easily halves the noise of the gun, making that pleasant putt-putt sound. Cool, because the UTG is louder than my TM in the first place by a long shot. It also doesn't affect accuracy either. I didnt have to pay $75-$90 dollars for a CA SD front end just to get the look I wanted to get. And I dont get any @#$% from people about having a UTG gun. They don't make an SD version yet anyway, so it looks like a TM. I can post some pics if there's enough responses or any questions on regarding how to make this conversion. It is a VERY simple thing to do, and should only cost about thirty bucks on Ebay to buy the CSI gun. I've seen it for less on clearance on different sites too now. It's like a sore peter, cant beat it, from the money spent aspect. So good luck and happy hunting!

[Shadow_at_your_six]

Good idea I might try that myself and make that CSI hunk of plastic in my room uselful!

[hivemind]

Pics please! Sounds like a fun project.