NFOA MEMBERS FORUM
Handguns, Rifles & Shotguns => Rifles => Topic started by: OnTheFly on February 22, 2012, 12:31:21 AM
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Been surfing the web and found some comments about an AR-15 Drop-in Trigger Adjuster...
http://weww.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2063387&page=1 (http://weww.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2063387&page=1)
http://www.brownells.com/.aspx/pid=307/sku=072-000-001/Product/AR-15-Drop-In-Trigger-Adjuster (http://www.brownells.com/.aspx/pid=307/sku=072-000-001/Product/AR-15-Drop-In-Trigger-Adjuster)
Found a thread on ARFCOM discussing essentially the same thing...
http://www.ar15.com/forums/t_3_4/457823_Trigger_Wow__RANGE_REPORT.html (http://www.ar15.com/forums/t_3_4/457823_Trigger_Wow__RANGE_REPORT.html)
First, let me say, yes I am going to be careful. And I know that I can just buy a 2-stage drop in trigger, but I thought I would give this a try first. If it doesn't get me close to what I'm looking for, then I'm only out $20.
The AR15.com link is occasionally a heated discussion about this adjustment, but the guy doing the mod has put several thousand rounds through the gun without a problem. I will give a report when/if I use it in my rifle.
Fly
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but the guy doing the mod has put several thousand rounds through the gun without a problem.
That's what he said online.... MUHUUUUUUHAAAHAAAH!
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I have done that mod with all my stock triggers, but I won't pay that much for a screw job... So I have done a WECSOG method
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Found an animation from Bushmaster showing how the standard AR-15 trigger, sear, hammer, and disconnect work. Pretty cool...
http://www.bushmaster.com/anatomy_bushmaster.asp (http://www.bushmaster.com/anatomy_bushmaster.asp)
Fly
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I love those kinds of animations. Good find!
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I sent an email to PR361 who started the AR15.com thread above. Here was his reply...
I still am shooting that same trigger in my one and only Armalite. It has not been touched since the day it was installed, except to add grease when I clean the rifle. It has never been back out and I have had zero issues.
Also, I've done that trigger fro a dozen friends, and not one issue so far. I think the concerns about damaging the case hardening are over rated. My rifle probably has 2500-3000 rounds through it now. If the trigger starts to give me trouble, I'll invest another $35 and do it over. It's working great, breaks consistantly at 4 lbs on my Lyman electronic trigger guage. Just shot it last week, check out the attached target.
Good Luck,
Fly
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I've been meaning to try this. The stock trigger on my 18" rifle is definitely hurting my group sizes. For 3 gun it's not a big deal, but for precision shooting it would help.
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Let us know how it works for you. I'm not a fan of these kinds of modifications but I am a curious guy. ;)
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I'm generally not either, but if it's sealed in with loctite I don't see it causing a problem.
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I'm generally not either, but if it's sealed in with loctite I don't see it causing a problem.
I'm not an engineer, but I have stayed in a Holiday Inn Express. If the set screw were to move, I would think it would move towards the original position (no partial trigger pull). In other words, the trigger is constantly being pushed down in the back due to the trigger spring. So I think loctite would be necessary to maintain your partially pulled trigger setting, but failure of the loctite should just mean that your trigger slowly goes back to the original l-o-n-g h-a-r-d pull.
Fly
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I received the drop in trigger adjuster and it is installed. Except for finding a LONG small size allen wrench, it was a simple job. I used a friend's scale to check the weight of trigger pull before and after installation. With or without the adjuster, the trigger pull is right at 7 1/2 pounds. So no change there. Regarding the length of pull...it does feel considerably shorter, but I'm trying to figure out a way to measure that. Anyone have an idea?
When I first installed the adjuster, I had screwed in the adjuster too far. It made the trigger pull very short and crisp, but the safety would not engage. After backing out the screw 1/4 turn at a time and then re-installing the pistol grip screw, I finally got it to a point where the safety will engage. The adjuster has taken out what appears to be a noticeable amount of trigger pull length. I think if I lightly (yes...VERY lightly) buff the sear, etc. it may make it quite smooth. My friend who shoots and does quite well in the high power matches with his target AR-15 said he was surprised at how good my stock trigger feels after the mod.
I have also considered cutting a small notch in the disconnector to allow the adjustment screw to push the disconnector a little further up. I have also been thinking about a slight modification to the springs to make the trigger pull a little lighter. If I botch up the springs and/or disconnector, they are not very costly to replace.
Fly
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Don't mess with the disconnector
The issue you are dealing with is called "creep" and is addressed by modifying the hook on the hammer
(http://i85.photobucket.com/albums/k44/jdn181/HammerModClose-up.jpg)
or by grinding a bit off the tail of the trigger so you can remove more creep with your special adjuster without jamming the safety
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Don't mess with the disconnector
The issue you are dealing with is called "creep" and is addressed by modifying the hook on the hammer
or by grinding a bit off the tail of the trigger so you can remove more creep with your special adjuster without jamming the safety
Hmmm...I like that idea.
Fly
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AGP lowers come with a built in creep screw forward of the pistol grip screw hole. You access the screw between the trigger guard and the pistol grip, so adjustment is easy and you don't need to take your lower apart to adjust it.
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AGP lowers come with a built in creep screw forward of the pistol grip screw hole. You access the screw between the trigger guard and the pistol grip, so adjustment is easy and you don't need to take your lower apart to adjust it.
The only thing you may have to do with the grip screw adjuster, if you can't find an allen wrench long enough, is to remove the grip screw a few times until you have it adjusted correctly. But even that can be a little bit of a pain in the posterior.
Fly
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I work as a toolmaker and made one of these trigger adjusters myself, and I had the exact same result as OnTheFly. It didn't reduce the trigger pull weight, but it did take some of the slack out of the trigger. I also had a little trouble with the safety clearance, as well as the disconnector not engaging properly when the adjustment was cranked a little too far. After messing around with it a while, I got it to where it works fairly well. Comparing it to my friend's stock DPMS Oracle, you can notice a slight improvement.
However...I honestly wouldn't have done the modification if I had to buy the components. Luckily I was able to do this modification for free, just to try it out. I would rather spend the money on an upgraded trigger system otherwise. Although you can notice an improvement, it's not very much, and if you want the best results from this you're probably going to have to modify some of your hammer components (if you know what you're doing).