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Discussion Starter #1 (Edited)
I just acquired a retired law enforcement issue UPS .40.

I would appreciate advise on how I can improve the trigger pull from it's current long hard pull before the hammer falls to something more manageable. Is there a drop
in trigger assembly I can purchase? if so where?

Are there trigger mods I can do myself?

I have shot the gun many rounds and would still like to lighten and shorten the pull on the trigger.

thanks for you help in advance. randy
 

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Discussion Starter #3
OK i un-bolded. what's your advise on the fix?
 

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I have not upgraded mine yet, however, I've heard the match trigger upgrade is amazing. HKparts.net has been out of stock for a while. A lot of people do it themselves, and I am going to attempt it whenever I get one.
 

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Discussion Starter #5
I have not upgraded mine yet, however, I've heard the match trigger upgrade is amazing. HKparts.net has been out of stock for a while. A lot of people do it themselves, and I am going to attempt it whenever I get one.
Can you tell me what it is you are going to do your self? What is it that has to be done?
 

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You really can't do anything about the horrible 10 pound DA trigger on the USP unless you convert the system to LEM. And even that won't help unless you install the Light LEM springs.

Search for LEM and get ready for several evenings of reading. Kitchen table "gunsmithing."

-- Chuck
 

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Discussion Starter #7 (Edited)
You really can't do anything about the horrible 10 pound DA trigger on the USP unless you convert the system to LEM. And even that won't help unless you install the Light LEM springs.

Search for LEM and get ready for several evenings of reading. Kitchen table "gunsmithing."

-- Chuck
thanks Chuck for the advise. I'll do the research.
 

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Discussion Starter #8
Thanks to Big Bore for answering my question:

In answer to the question, “What exactly is the LEM trigger?” here is a brief synopsis.
In the P2000/SK pistol, as well as an LEM USP/C or LEM HK45/C, the LEM trigger is a DAO light action trigger that has the same trigger pull weight first shot to last.
The first shot will have a long but light take-up and then will release the hammer and fire the pistol at a factory pre-set pull weight. In the standard LEM V2 version, the trigger releases the hammer at about 8 pounds of pull. In LEM V1 the pull weight is 5 pounds and LEM V4 the weight is 7 pounds. The various weights are achieved by trigger return spring and firing pin block spring changes. V3 is not an LEM trigger but is SA/DA and it functions and feels the same as the V3 trigger in the USP/C pistol.

The LEM light action system uses a two-piece hammer arrangement such that when the slide is racked or a round is chambered (by racking the slide) the lower, unseen part of the hammer is brought to full cock position and the hammer spring compressed. The hammer “spur,” or top part of the hammer, follows the slide forward and the pistol appears to be “decocked” but the pistol is still in a 90% cocked condition.
When you shoot, as you pull the trigger the hammer will come back to the full cock position. As you reach the release pull weight, the trigger will release the hammer and the pistol will fire. If you hold the trigger fully to the rear as the pistol cycles the next round, you only have to let off the trigger .3 inch to reset the trigger. At that point the same amount of trigger pull weight, except for the long take up, will fire the pistol again. You will notice that after the pistol fires the hammer will be in the full cock position if you did not release the trigger, but as you release the trigger to reset the trigger, the hammer goes forward about 1/3 the way. After reset, as you pull the trigger again the hammer comes back again to full cock. If you release the trigger all the way then the hammer will go all the way forward into the “decocked” position, but remember, the hammer spring is still fully compressed and ready to fire and will do so with a light, but long pull of the trigger. The hammer spring cannot be decompressed without pulling the trigger so if you wish to do this, there had better not be a round in the chamber!

The LEM also has repeat strike capability. If for some reason the pistol does not fire, and you wish to try to ignite the round again, you do not need to rack the slide to pre-load the hammer spring. You only need to pull the trigger again which will fully compress the hammer spring and release the hammer. However, starting from the fully uncompressed hammer spring condition the pull weight will be between 11 and 13 pounds, similar to the DA pull on the non LEM USP/C. After the round fires or you rack the slide (which pre-loads the hammer spring), you will again have the light LEM pull.


The difference between it and the standard trigger is with a V1 standard trigger, you can start from a hammer down condition where the first shot will be DA and have a 10-11 pound pull weight as you fully cock the pistol and fire it. After firing, the hammer will stay back in the full cocked position even if you release the trigger fully and all shots after that will be in a SA mode with a trigger pull of about 4-5 pounds unless you decock. The reset on the SA trigger is roughly .254 inch but if you release the trigger all the way, you have about 1/2 inch of take up before firing the pistol at the lighter SA trigger pull weight (if you release the trigger all the way on a LEM trigger you also have the long take up before you fire the pistol again).
Many do not like the transition from DA heavy first shot pull to follow up SA light trigger pull.
If you release the trigger after shooting the hammer stays fully cocked and in SA mode, so if you want to decock it you use the decocker to safely drop the hammer and release tension on the hammer spring. You cannot release tension on the hammer spring with the LEM trigger without pulling the trigger, which will fire the pistol if there is a round in the chamber. There is also no manual safety on the LEM trigger but on the USP/C and HK45/C a manual safety can be retained with the LEM trigger. No safety can be added to the LEM P2K/SK firearms.
 
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