LEM Parts Swap HK45 - USP

[hardscrabble]

I bought an HK45 (BC date) that was originally a V1, had been converted to LEM, but included the original parts. I also own a V3 USP 45 (BG date). I own a P30 LEM and a P2KSK LEM. I’m familiar with the system, the parts and I converted the P2K, so I’m not totally inexperienced with LEM conversions.

I pulled the LEM parts out of the HK45 and returned the pistol to V1. I’m not crazy about it. I figured I would either sell it or give it another shot later. I had in mind a USP 9 Compact acquisition, and use the kit in it (I see more V1’s for sale than LEM’s). But, I have an elk hunt coming up this fall in big bear country. I got caught up reading the ‘field pistol’ thread and started thinking my USP, in LEM and shooting 45 Super might be worth trying, since I had the spare kit. So l did a quick post just to be sure ‘hey my LEM kit out of my HK45 will go right into my USP right?’ and I was assured it would.

I put it into my USP and it wouldn’t fit correctly. I could get the parts into the frame, get the pin in (parts didn’t want to line up) but they were obviously a tight fit and wouldn’t function. The hammer would go back and release off the sear, but wouldn’t fall. I took them out and tried again, same result. Then I took it out and put it back in my HK45. Perfect fit and function. Back to the USP, wouldn’t function. I had no problem in and out of the HK45 twice. The only hitch I encountered with the USP was that the trigger bar was harder to keep in place on top the plunger, but I was doing the work under the lights at my fly tying table and a hackle plier worked to hold it in place. That and the hitch that the damnable thing wouldn’t work: parts installed in order, per instructions, hammer assembled correctly, etc, and again, I installed it back in the HK45 twice without difficulty. Both these guns have the newer 2-piece catch.

Not a huge deal. The HK45 was local and priced right. I like the V3 USP, and wouldn’t have left it LEM anyway. But, I’d like to use the parts eventually to convert a compact. Thus the questions:

Was there an early version of the LEM kit that isn’t interchangeable between HK45 and USP models?

Any ideas?

Thanks for any help.

[fatdog]

I encountered an early 90's USP where I had to also upgrade both the catch and sear actuator as part of LEM installation for it all to work. Those are not parts in the current LEM kit but the current LEM parts, particularly sear and hammer, would not fit and the sear would not work with the old style versions of those two components. The new version of those two parts will work with both LEM and V1 parts.

[hardscrabble]

Thanks. I would likely cut and run before investing another $half-hundred + in an attempt to make it work in the USP. I can always put it back where it came from if I want an HK45 LEM.

When I get around to it I’m going to mic all the parts to see if there are dimensional variations.

[entropy]

Look at hkparts.net. If you scroll thru the various parts and descriptions, you should find your answer. Also give this a try:

https://www.hkpro.com/forum/hk-refer...t-numbers.html

[Gray Ghost]

Call H&K customer service. I have found them to be ridiculously helpful. Like they pay shipping both ways and turn the gun around the same day they get it even thought I told them I bought I used helpful.

[entropy]

A bit of an update on progress. I finally had the opportunity to get it out into it’s intended environment and do some shooting. I ran a few hundred rounds of S&B 230gr FMJ through it, along with some HST to assure feeding and compare POI. As expected with anything HK, it ran without a single hiccup. The frame size difference between the .45 and the USPc wasn’t really apparent until I started running drills. Years of engrained grip habits and feel/handling showed up a bit in the results. Impacts generally were about an inch to 1 1/2” low and left. (I’m right handed.) The “occasional yank”...which I have fought to overcome long and hard over the years with the compact came back too. I imagine both are due to the slightly different ergonomics associated with the larger frame. That’s just practice and it will alleviate I believe once I get more rounds downrange with it. Along with that, I experienced some fatigue associated with the the heavier TRS. I get the same thing with USPc #1 after extended practice sessions. (That one is set up as “heavy”.) Again, I believe to the slightly different ergonomics. I might fiddle with that a bit by installing a lighter FPB spring and/or reinstalling the original (lighter) TRS. Maybe my aged butt just needs to sit and squeeze a tennis ball while watching TV too...

A few minor issues with the holster as well. Using the QLS threaded belt attachment along with a single thickness Beltman belt, I had a bit of “droop” or “pull away” while carrying. I believe this is due to the much heavier grip frame of the .45, along with the fact that the QLS attachments provide enough gap between the body and the holster/body to allow that droop to naturally occur. I didn’t have the paddle attachment with me to swap and compare (I actually find the paddle holds the holster a bit closer to the body) nor did I have different belts to swap out for a support comparison. I’ll try that out when I return home.

Overall, despite the above, I’m happy with it. It functioned flawlessly, feels familiar enough that I can adapt to the size difference, and is certainly accurate enough to more than satisfy that requirement. Most of the testing was done at 15yds both on paper and steel. Ragged holes were the norm (although as stated a bit to 7 o’clock) and “head shots” on a 2/3 IPSC plate were pretty easy. I’d post the obligatory pic, but the steel has been painted over, and the cardboard is just a ragged scrap at this point filled with pasters.....so....

[Exiledviking]

... Along with that, I experienced some fatigue associated with the the heavier TRS. I get the same thing with USPc #1 after extended practice sessions. (That one is set up as “heavy”.) Again, I believe to the slightly different ergonomics. I might fiddle with that a bit by installing a lighter FPB spring and/or reinstalling the original (lighter) TRS. Maybe my aged butt just needs to sit and squeeze a tennis ball while watching TV too...

After trying several different combinations of TRS, FPBS, and HS springs in my LEM pistols, I have come to prefer the light FPBS regardless of which TRS is used. To me it makes for a much smoother trigger pull having the light FPBS with either weight TRS.

My preferred combination has become the light FPBS and heavy LEM HS with either the light or heavy TRS. The TRS version depends upon the intended usage of the pistol.

[entropy]

Nuts!

Meant to post this in the “Field pistol thread”

Must be getting senile or something. Sorry all.

[Exiledviking]

Nuts!

Meant to post this in the “Field pistol thread”

Must be getting senile or something. Sorry all.

Ha ha ha. I thought that's where it was posted when I replied to your post. Doh!