HK USC to UMP Self Conversion Review

[JustinJ]

I completed my HK UMP build over the weekend and got a chance to run it.

Total cost broke down as follows, excluding tools:
HK USC new(black)-$1300
HK FBI Lower- $300
HDPS Stock Block: $200
UMP Mag - $60
US Mag follower and floor plate (2 992r parts) - $25
UMP Armorers Manual - $25
Top Rail: $40
Bottom Rail: $30
Top Notch US Stock (1 922r part) - $100
SS Stock Hinge - $20
total - $2100

Swapping the trigger group wasnt terribly hard. The armorer's manual turned out to be of limited use for this so instead i found a good how how to guide with clear pictures on HKPro. I opened the hooks of the UMP lower with round files and got a nice fit. The hardest part was opening up the magazine hole in the bottom of the upper. I tried to use a x,y cross vice on my table top drill press but there wasnt enough room to properly insert the upper in the vice grip for proper orientation. Instead i attached a scope base to the top rail and held that with the vice. Unfortunately there was excessive wobble while milling so my cuts werent nearly as straight as I'd like. The polymer material of the upper flexed too much. Luckily the magazine is secured by the lower mag well so the upper receiver opening isnt important to functioning so long as the mag can seat properly.

I took her to the range yesterday and ran about 150 rounds of federal FMJ. It ran flawlessly and i was more than happy with performance. Looking back however i do wish i had sent it off to be converted professinally as it is fairly inexpensive. The biggest reason i did not was not wanting to deal with the hassle of mailing it. I had a bad experience before. Plus i really didnt want to wait so decided to do it myself. Although performance is perfect collector value would be higher had i let a professional do it. Plus i still need the vent cuts at the foregrip. My next step is to SBR, get a UMP length barrel and silencer. Instead of the true UMP 3 lug barrel i'm going to either chop and thread my barrel or buy one arleady done. I want a can that will fit on my .45 pistols as well.

 

[SHOTGUNJIM]

How about some pictures?

 

[JustinJ]

I'll try and get some up later this evening.

 

[Rubber_Duck]

Tag for pics.

 

[JustinJ]

Pictures as requested.

 

[mr.trooper]

Cool! Good job on the conversion for sure.

I have a buddy who did a similar SL8 to G36 conversion.

 

[Rubber_Duck]

Looks great, probably cost a lot less than an HDPS conversion. Well done.

 

[JustinJ]

Thanks, Rubber Duck and Mr. Trooper.

I actually saved a lot of money by shopping around for parts. The best deals i found were the gun itself and the lower for $300, which usually go for $400. The labor from HDPS would have only been about $100 but buying one of their upgrade packages would have been much more due to their cost of parts. Plus, i dont think they sell the american stocks so i would have had to pay extra for a real HK stock and then an american trigger for 922r compliance.

I've been thinking about a SL8 to G36 conversion but I dont like the fact that certain factory parts have to be replaced. Plus they tend to be very expensive. HK recently announced the discontinuation of the SL8 so if anyone else is thinking of doing it you had better get your gun and parts quick.

 

[CraigC]

If HK marketed one like that off the shelf, with magazines that held more than ten rounds, I would probably buy one. We need a good .45ACP carbine on the market.

 

[Rubber_Duck]

+1 on the above, agree completely on HK selling non-neutered USCs. I've wanted one for a long time but can't pony up the cash for one fully-converted (to include SBRing it).

 

[JustinJ]

Dont blame HK. The USC is neutered to comply with US laws. Another much cheaper option is the Grease Gun mag conversion. I've heard that they arent very pretty but run great plus GG mags are much cheaper. Small Arms Review gave the GG conversions a great review. The stock on my UMP conversion is made by the GG conversion maker, Top Notch, and I found the color and texture to match the upper very well.

 

[Frogomatik]

very cool, I'd love to have a "UMP" but I just can't bring myself to give any of my money to H&K

 

[JustinJ]

Frogomatik, what makes you say that? I know HK products tend to be expensive but in my opinion they are truly the best and highest quality. I think HK has tried harder than most realize to serve the US civilian market but that effort is often thwarted by German and US laws. They are now producing some guns in the US so i think more of thier product line will become available to civilians. Lets just hope their US factory doesnt go the way of Sig.

 

[Frogomatik]

My reasoning is based on what experience I have shooting other people H&K's. They are good guns, but not particularly better than any other quality gun, and certainly not enough better to warrant the leap in price. In my opinion they want more than their guns are worth. I've got guns that are just as accurate, 100% reliable, and cost less than half what H&K is asking for something comprable.

 

[JustinJ]

Frogomatik, i think where HK really shines is not just their reliability but their durability in any environment which is why special forces carry them all over the world. Glocks are great and i have one but I'd take an HK to war over it any day. And believe it or not I have heard of people having issues with Glocks although more so with certain models. I cant say the same for HKs.

 

[Frogomatik]

Justin. I had a hi-point that never recieved any care, was abused and mistreated, and still shot on the money, and never had a failure, and that was a $100 gun. I beat that gun to death and it still ran like a champ. I eventually gave that gun to a friend who continued to abuse it as I had, and it finally had a part break after 6 years of abuse. She sent it to hi-point, they fixed it, gave her a free extra mag, and hi-point paid for everything.

I'm not bashing HK, I think they make fine guns. I also think their pricing is excessive. There are guns that are the equals of HK for considerably less money.

on the subject of glocks...I really really dislike glock. Not becuase of any performance or "grip angle" issue, but from a standpoint of design. nearly every single time I hear or read about someone shooting themselves or having a ND while cleaning a gun, the gun is a glock. The dissasembly procedure is, in my opinion, a design flaw. Funny thing is, I didn't have anything against glock untill I took their armorers course. Now I'm certified for em, and wouldn't keep one in my house...lol

If I had to go to war...screw all the fancy stuff, just hand me a kalashnikov

 

[JustinJ]

Frog, i'm with you on the Kalashnikov. My arsenal ak74 is the first thing i'm grabbing if all goes to hell.

Its funny you mentioned a High Point because i have an old 9mm that i've been practically unable to give away. I havent shot mine that much but havent any problems either. On the other hand i've heard horror stories about the slide flying off when fired. I'd rather shoot msyelf with one than take a highpoint to war. My point is anecdotal cases aren't revealing about the overall quality of a gun model or manufacturer which is why i say take gun review mags with a grain of salt.

HK prices are definitely high compared to many other guns but i think HK guns as a whole are generally higher quality than any other production gun. Is it of a degree to justify the added expense? Thats a subjective call but for a civlian owned weapon there are cheaper guns out there that are more than adequate. But i do like the added comfort of having what i believe is the best. HK is also a very innovative company so they probably spend more on R&D than most others which I would guess is part of the reason for their cost. I sort of doubt glock broke the break to design the gen 4 models.

 

[Frogomatik]

I certainly agree you on anecdotal evidence, and didn't mean my example to be indicative of all hi-points. I was just pointing out that even cheap guns can be of acceptable quality. Also, there's no way I'd take a hi-point to war, if only because they are rather cumbersome, though if I ever needed a hammer, the hi-point would do just fine...lol

If HK's were a less expensive, I'd be happy to own one. These days I have to be very frugal with my money, and that means HK isn't for me. Now if I won the lottery, I'd gladly pay off the right people to get a proper UMP.

 

[JustinJ]

Good point about the highpoint as a hammer. Would be a new meaing for the term "tack driver".

Believe it or not i picked up a like new P2000 .40 for $450 a few weeks ago while buying my USC. I couldnt believe the price so grabbed a big brother for my P2000sk .357 sig.

 

[HauptmannAmerika]

JustinJ, question for you: I noticed you only mentioned three (3) 922c compliance parts, which ones make up the other two (2)? I ask because I just got my USC and want to do literally exactly the same thing you've done and plan to do. Also, which vendors would you recommend to buy the parts from?

 

[greyling22]

cool gun. CraigC, in your search for a 45acp carbine, don't forget the kriss super v.

 

[FIVETWOSEVEN]

Dont blame HK.

They do have a manufacturing plant stateside, they could do it if they wanted to.

 

[MachIVshooter]

Dont blame HK. The USC is neutered to comply with US laws.

Bravo Sierra.

We have all kinds of stuff coming in from Europe, including Germany. Just look at the Sig and FN stuff. Do you really expect us to believe that there were laws that made the UMP into the USC and G36 into SL8, but somehow the Sig 556, FN SCAR, PS-90, etc. were exempted for some reason? All they're missing is the short barrel and fun switch.

It's HK's "Well, we'll make something kinda like what we sell to law enforcement for you lowly civilians, but we're gonna make it look more toy-like and limit you to 10 round mags, even though the ban is over. But don't worry, you'll still pay a premium for our name on the side...." attitude.

I'm glad you like HK toy, but IMO, $2,100 is way too much money to spend for something that is no different functionally from the $600 Beretta Storm or $300 Hi-Point 995. All just pistol caliber carbines in the end anyway. If you've got the coin and it's what you want, more power to ya. But it is definitely a case of fashion over function.

 

[FIVETWOSEVEN]

Just look at the Sig and FN stuff.

Made in the USA.

The SIG may have parts coming from over seas but I doubt it. The PS90 has a muzzle break and thumbhole stock so having a detachable mag is okay under 922r to my knowledge.

 

[browningguy]

Thanks for the writeup, I've been considering whether to change my USC to either a UMP or the GG setup.