I recently had a gunsmith install the DCAEK on my full size M&P 9mm (bought in Jan 2016) and it has not lightened the trigger pull from stock. Using a Wheeler gauge, the stock gun was 6.5 lbs and with the DCAEK it also runs 6.5 lbs. The gunsmith took apart the gun and re-installed the DCAEK - no change. Apex has been great in responding to my e-mail questions and even sent me a new trigger return spring. I have all the old parts and sent photos to APEX. I know the correct parts were installed. I am waiting for a call from a gunsmith at APEX.

Has anyone else had this problem? Any ideas as to the cause? Could the APEX seer/seer spring be defective?

Discussion:

I measured the trigger pull to the point of contact with the seer both with and without the slide. It was consistently 3.0 lbs without the slide and 3.25 lbs with the slide (done by tactile feel). With the slide on the striker block is engaged so the slight increase in pull is expected.

According to what I've read from several sources (here, APEX and elsewhere), I could replace the factory trigger to lighten the trigger pull (~1.5 lbs) but I like the feel of the gun with the heavier spring. Tactile reset is excellent and I feel this would be sacrificed with a lighter spring. In any case this is not really a "fix" as the "staging" of the pull required to release the striker would be compromised as this is not the way the kit is supposed to work.

Let me explain my thinking...current trigger staging = 3.25 lbs of pull for the trigger engage the seer + 3.25 lbs of pull to release the striker = 6.5 lbs.

If the DCAEK is supposed to reduce pull weight to a max 5.5 lbs (upper spec), and assuming my spring is functioning properly, then an additional 2.25 lbs (after seer engagement) should be required to release the striker. The correct staging is therefore 3.25 lbs to engage the sear + 2.25 lbs to release the striker = 5.5 lbs.

Installing the factory spring should lighten the pull by 1.5 lbs to 5.0 lbs. This would change the first part of the trigger staging - 1.75 lbs to engage the striker. However, the same 3.25 lbs additional force would still be required to release the striker. Resultant staging is 1.75 lbs to engage the sear + 3.25 lbs to release the striker = 5.0 lbs.

The difference in staging should be most noticeable when firing the gun from the reset point.

In summary (on a relative basis), I have a heavy to heavy action, the DCAEK should yield a heavy to light action and replacing the spring (with factory) would yield a light to heavy action.

Conclusion:

The installation of the factory trigger reset spring, while lightening the trigger pull, would still not give the results I am looking for.

Comments?

I went though the same when installed the kit on my 45c, I don't know how many times I went back n forward trying to figure it out what was wrong until apex responded me saying that their trigger return spring is heavier than the stock to compensate the -2lb from their sear. I ended leaving the stock return spring and I am very happy with it, they also recommended polishing the trigger bar and striker block, and if I wanted a lighter trigger pull I should install the competition striker spring. Not sure if that helps.

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M&P 9, Shield9.

When I installed the Duty/Carry kit into 2 of my full size 9's, I kept the stock trigger return spring. While the reduction in trigger pull weight was not tremendous, it was definately better. I don't have a pull guage, but it seems like the reduction was about 2 lbs. I had previously had a friend check one of my 1911's, and that came in at just under 5 lbs, and the two 9's now are very similar in pull weight. They certainly are not as nice as the 1911, but acceptable. The used 9 Pro I picked up a few mnths back has stock internals, and it has a trigger pull very much like the 2 with the Duty/Carry kits.

I didn't go w/ the whole kit, I just installed the duty/carry spring. I also like the heavier first part of the pull. But then the final part was too heavy. I did the DIY polishing which helped. The final fix was to open up the gap on the loop on the trigger bar. This creates a more gradual angle for the bar to move the sear with.

After all my overanalyzing...I had the gunsmith who installed the DCAEK check the trigger pull several times in August. Each time the average of 5 readings was 5.5 lbs. My gauge at home still reads 6 - 6.5 lbs.

I shoot 100 - 150 rounds/week so after 4 months and ~2,000 rounds, I have forgotten about the "questionable" trigger pull and absolutely love the feel of the trigger action with the DCAEK. I never changed the spring back to factory...I use the spring which came with the DCAEK. The kit performs just as advertised - smoother trigger, lighter feel, shorter and more tactile reset. All resulting in better accuracy.

I guess it took quite a few rounds to break in both the kit and my head.

Update - I bought a compact Walther PPS (great factory trigger) a few months ago and fell in love with it including the 5.5 lb trigger pull weight. I have gotten pretty accurate with the compact PPS to the point where it rivaled the M&P 9's accuracy. So now 10 months after shooting with the full Apex DCAEK (with a mysteriously heavy 6.5 lb trigger), I replaced the Apex spring w/ the factory spring to reduce the trigger pull weight and improve accuracy. The pull on the trigger is now just a hair under the 5 lbs spec on the Apex kit. What a huge difference going from a 6.5 lb pull with the Apex spring to the 5 lb pull with the factory spring - MUCH lighter break. I shot my "new" M&P at the range this week for the first time ~100 rounds. The only negative is the reset is not as crisp and audible with the lighter spring (as expected) but it is still vastly improved over the factory setup. Break is crisp. As far as accuracy goes, it wasn't my best day at the range with either gun so the jury is still out as to whether I keep my M&P 9 or or trade it in for the full size Walther PPQ I've been looking at.

It's still a mystery as to why my Apex DCAEK never reduced the trigger pull but after 10 months of shooting a compromised setup, I now have my desired 5.0 lb trigger on my M&P.

I have Apex Duty Carry Kit on 4 guns, they all have a nice crisp break and audible/tactile reset, trigger pull is 5lb on all 4 consistently.
I don't know why yours was the exception, perhaps your gunsmith missed something IDK. I did the installation myself, never had any issue. In your case I would have sent the gun directly to apex.

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M&P 9, Shield9.

"What a huge difference going from a 6.5 lb pull with the Apex spring to the 5 lb pull with the factory spring - MUCH lighter"

Didn't you decide the 6.5 reading was your faulty pull gauge? Some of your perception may be subjective. A lot goes on in the human brain..!

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CERAKOTE Svcs.
Class 01 FFL

OK, so I can be a head case at times with this gauge stuff. When I got my PPS, the gauge was spot on with the factory spec - 5.5 lbs. That's when I started believing again that there was indeed an issue with the DCAEK having a heavy trigger - 6.5 lbs on the gauge.

Went back to the range today...best session since last July...actually best session ever in my 17 month shooting career.

So, all is well at this point - I'm happy with the factory spring in my DCAEK install. I have a lighter take up which means less tension in my finger when I stage the trigger. The problem with my DCAEK install turned out to be a blessing in disguise. I now have the lighter take up of the factory trigger, a crisp 5 lb break, + the other improvements from the Apex kit.

I am thinking about adding the DCAEK to my Shield, but I am not sure if I should use the springs that come with the kit. There are 2 springs plus sear spring. So, is the only spring some are changing the return spring and leaving the other 2. Also, some have mentioned that they just buy the sear and striker block and not the kit.

You didnt mention what gun. I believe you have a 9mm because you spoke about wanting a 45 a few days ago.

On the 9mm....I have one that is well broken-in, around 2k rounds. I went with the sear only. Trigger pull dropped from 6.5 down to 5. A tremendous difference. Its on mamas gun and its soooo smooth she outshoots me and her two boys now.

I modified the factory sear and dropped it in my new Shield45. Not an appreciable difference because I was a little too conservative with my filing (been too lazy to pull it back out)

Shield9mm will be along shortly to brief you on installing the entire kit (and he loves it BTW)

Another update...I've been shooting with the factory spring for 4 months now. I've noticed the trigger feeling much lighter compared to my PPS so I decided to check the trigger pull again. Now the M&P trigger breaks at 4.0 lbs consistently. Great for the range but too light for home defense. My Walter PPS still breaks at the 5.5 lb factory spec so I'm confident that I'm measuring correctly.

My thinking is that the M&P is now fully broken in with 10,000+ rounds,~2/3 with the DCAEK installed.

I'm going to re-install the APEX trigger spring and expect a 1.5 increase to 5.5 lbs which is what I was expecting from the beginning. I'll keep you informed.

Put stock trigger spring back in and enjoy about 4.25#

Certainly things can vary... my experience has been consistent with shield9mm. I installed my Apex kits. I suspect your gunsmith mixed up the springs somewhere in the install.
Both my triggers have remained the same since I installed them. 2k on one gun and 1k on the other. But I haven't ever measured the pull.
I had a PPS until June. I bought my Shield in May, installed the DCAEK right off. After several range trips with just the Shield. In June I finally brought along the PPS and shot them head to head. Sold the PPS the next week.

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Got Apex?

Read again, I have the stock spring installed and I am consistently at 4.0 lbs. As I said, great at the range.

Interesting...I bought the PPSM2 in January after shooting both the Shield (stock) and the PPSM2 head to head. I'm no treal happy with the way I shoot my PPS. Everything is consistently left which may be the sights and I do not like the groupings which has nothing to do with the sights. I'll give the shield another look.

I bought my PPS just before the M2 was released. I liked the size and shot it great but the grip on the Shield works much better for me.
If there was no Apex trigger option I would likely have an M2 now. I was happy enough with the PPS that I wasn't going to spend $400 and another $130-ish on an Apex kit.
But then came the rebates... which allowed me to get a Shield and Apex it for under $400. I added night sights and I'm very happy. I shot the PPS well but never enjoyed shooting it. I shoot the Shield just as well and I enjoy shooting it.

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Got Apex?

Had a pps m2 still like the shield better.


Sent from my iPhone using Tapatalk

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M&P 9, Shield9.

One thing to remember (or hear for the first time) is that all the apex springs (with the exception of some of the competition springs) are actually heavier than stock. The sear spring is especially heavy compared to stock. When you stack the spring tension between the trigger return spring, the sear spring, and the striker block spring, they can feel a bit stiff. The duty/carry it's aren't designed to lighten the pull too much and gun tolerances vary. As you have noticed, the apex springs are tight when bar and new but settle very nicely after some trigger pulls. I have played around with different combos and adjustments and you can end up with some very light pulls with some set ups.

The regular apex trigger spring (not the green painted one) does increase the feel of the reset and I can't really figure out why.... I can't quite grasp the physics of that one. Only thing I can think of is that the extra tension being applied to the bar is slightly stiffening the bar or something. Or maybe because of the shape of the bar it's actually pulling it into the sear block... it doesn't seem to me that's what's happening with my studying but I haven't looked at it that much.

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Equal opportunity shooter