Completely honest, I used this on a binary trigger in an APC9 Pro because I wanted a heavier hammer spring for reliability. Needed this for a solid reset. Works like a charm!!!

I prefer the feel of this spring.

I love this spring. It works great and has a good clean crisp break.

This is a good trigger. Break is crisp and predictable. I shoot CMP and NRA Service Rifle in competition. As delivered, the springs are not good for precision shooting. To use the trigger the disconnector spring needs to be slightly lighter and the trigger spring slightly heavier. I have accomplished this and made this into a very good, repeatable Service Rifle trigger. We bought 8 of them in a group purchase. We would like to see LaRue work with the Service Rifle community and make a set of replacement springs.

It's a good spring and works how it should. Definitely closer to a polished mil-spec than a precision like trigger so a safer bet for the guys who want a heavier pull out of their "combat" rifle. What I'm not a big fan of is the weight staging. It seems like all 6 lbs. Goes into the take-up before the wall, then the break is roughly the same as the larue light spring which I've found to be very light and less than the 4.5 advertised. I get about 3.5 to just under 4 with the light spring. The heavy spring has a much better reset than the light but the pull distribution just isn't there. I wish it were something more like 3.5-4 on the takeup, then another pound or 2 for the break. I hate having too many options, but Larue should really think of making some kind of medium spring that is the best of both worlds. Slightly heavier pull with more of a pronounced reset. Unfortunately with the light spring, I find myself hunting for the reset or getting kicked too far forward when the reset does click. This heavy spring definitely fixes that, now if it just distributed pull weight better.

Here is the thing with this trigger: the trigger itself is great, the break, the shape and width of the bow, the materials and machining are all awesome. The problem comes from the trigger springs, with the "regular" spring the combined pull weight will be somewhere between 3 and 3.5 lbs and not the 4.5 lbs as advertised, and the difference is in the first stage and comes mainly from the trigger spring, this makes it a great trigger for a precision rifle but too light for a combat rifle. Now, if you were to put this heavy trigger spring in (one does come with the trigger) you end up with a very heavy pull, too much for any real precision work, the increase is mostly in that first stage making it a very heavy first stage, basically making the 2 stage trigger useless as a 2 stage trigger. I wish Larue would release a trigger spring that actually made it a 2.5lbs first stage and 4.5lbs combined but instead we get this thing which is neither here nor there. Now I personally ended up using a spring set from another company on my "goto" combat rifle and it gave me a 3 lbs first stage and 4.5 total, nearly perfect but just a tiny bit too heavy for a first stage, but, it is safer than the "standard" you get with this trigger and it is usable unlike this heavy spring. Hope this helps you guys, ideally most of you would want 3-3.5 lbs total for a precision rifle and 4-4.5lbs total for a combat rifle.

It's a trigger spring, it does what it's supposed to do. I didn't need it however as the heavier spring comes with the MBT trigger, $6 no big deal

This is a great trigger spring. Works great in my AR rifle.