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Discussion Starter · #1 ·
I just installed a Geissele Super Scar trigger in my 16S. It is certainly a major improvement over the stock 8lb. 2 oz. factory trigger. One observation – measuring trigger pull weight of the Geissele Super Scar trigger with my Lyman electronic trigger pull gauge yields results that range from 4.0 to 4.5 lbs. Now I was a little surprised by the fact the pull weight would vary by as much as 8 oz. from shot-to-shot. My surprise is based on my experience with another Geissele trigger – the SSA-E trigger that I installed in my SIG 716. The SSA-E trigger is extremely consistent from pull to pull, rarely varying more than a fraction of an ounce.

This variation in pull weights may be normal for this trigger, or it just may require some break in before it attains better consistency. However, if the spread in pull weights isn’t normal, I started to think about the factors that could cause the variation. One could be insufficient clearance between the new trigger and the oblong slot in the bottom of the lower, which would cause interference with the trigger’s motion. The installation instructions that Geissele packages with the trigger warn about this possibility. I was careful to look and feel for interference when I did the installation, but I didn’t observe any, so I made no attempt to modify the shape of the oblong slot.

So here’s my question: of those of you who have also installed the Geissele in their SCARS, has anyone found it necessary to relieve the oblong slot in the lower for the trigger? Has anyone else experienced a similar range in pull weights from shot to shot?
Thanks.
 

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Did you change out the factory grip screw? I don't think that is your problem but I have to ask. I haven't heard of anyone here needing to modify thier trigger module in anyway in order to accept any after market triggers. If anything I would think its a break in thing. One more observation is that the pull weight is supposed to be 2-3lbs... Or I thought it was.
 

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I haven't weighed mine, but it definitely developed creep in the 2nd stage after about 200 rounds. Very annoying after dropping $300 to get rid of the creepy factory garbage.
 

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Discussion Starter · #4 ·
Thanks for the reply. Yes, the grip screw has been replaced and doesn't interfere with the trigger. According to the Geissele website, the total pull weight is supposed to be 4.0 lbs. So it's close, but it's just the variation that I'm experiencing that is making me wonder. You are probably right though -- it will probably even out with more use.
 

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How much grease did you apply on the contact points of trigger module?

Also how many times did you take measurement? What are the actual spread of the results?
 

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Discussion Starter · #6 ·
I greased the contact areas with the supplied grease as directed in the instructions. You can only get a tiny dab of grease on those contact points so I don't think it's possible to over-grease. I took about 8-10 readings right after doing the installation. The extreme spread from those readings was 8 ounces.
 

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Did you make sure the trigger spring legs were straight? Mine second install went real fast compared to the first, but initally the spring legs were canted to the side, making mine feel mushy. Just had to straightem them out with a little screwdriver once I noticed the problem.
 

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Discussion Starter · #8 · (Edited)
Did you make sure the trigger spring legs were straight? Mine second install went real fast compared to the first, but initally the spring legs were canted to the side, making mine feel mushy. Just had to straightem them out with a little screwdriver once I noticed the problem.
Yep. I sure did. Spring legs are evenly spread and point toward the muzzle as per the directions supplied by Geissele.

Since no one has indicated that they found it necessary to relieve the oblong trigger slot in the lower, and since I could detect no interference there myself, I'm going to see if the trigger breaks in with use. I'll re-measure pull weights and if I still encounter an 8oz swing in the weights after putting 100 rounds through the rifle, I'll remove the trigger and relieve the oblong slot.

Thank you all for your ideas and help.
 

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Sorry - Bill was out having fun:
IMG_20071.jpg

I would detail clean - and re-apply grease on all points of contact that he advises (small area behind the sear) and a little goes a long way.

As Kam pointed out ... you get heavy handed with the grip screw it will cause issues - don't use the OEM use the one w/his trigger..his screw is shorter.

If still an issue pick up the phone and call him (610) 272-2060)give him a day or 2 as he is traveling after being here at FT Bragg for the 6th Annual USAJFKSWCS/USASOC Sniper Competition (Range 37) ... He more than stands behind his products, even if you may have inadvertently done something incorrect pre/post install.
 

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I've installed the Super SCAR trigger on both the 16S and 17S an have not had to alter either SCAR and have not noticed any variation in trigger pull weight. Advise above is the way to go.
 
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