Terribly Inconsistent Trigger Pull

[mwinter501]

Greetings everyone, I have been lurking for quite awhile and now need to chronicle some of your wisdom.

I recently purchased a STI Tactical 5.0 in .45 and have had a terrible time at the range. Sometimes the trigger pull is light (reasonably) and crisp. Other times, my hands are shaking cause it takes so much to get the hammer to fall. I first thought it was the over travel screw, but it doesnt do it at all when dry firing...only when actually shooting.

The only thing I can think of is the magazine is swelling in different places as the ammunition moves through causing it to close any gap between it and the trigger.

I tried to use the supplied allen wrench to back the overtravel screw out a little, but it rounded out. Im hoping to try one at home tonight to see if it works.

Does anyone have any suggestions for fixing this? Thanks in advance for your help.

[Hi-Power Jack]

Could be your grip - if you have a grip safety, you may not be fully engaging it each time.

[mwinter501]

Could be your grip - if you have a grip safety, you may not be fully engaging it each time.

I wondered about that, but ruled it out since it was always fine with dry fire and was so inconsistent from shot to shot. I have shot 1911's for years without any issue like this, but Ill check the grip safety when I get home just to be sure. I really appreciate the help.

-Edit-

Checked the grip safety and it disengages far out enough to keep me from thinking its the culprit.

Edited March 21, 2013 by mwinter501

[Hi-Power Jack]

You might confirm that by tying the grip safety tight, and see if that works.

When you say "always fine with dry fire", does that mean the hammer fell

each time until you loaded the gun and actually fired it? That would suggest

again, that it might be the grip safety and your grip on the gun. One of a few

possibilities - probably the easiest to prove or disprove .

[mwinter501]

When I say it's always fine with dry fire I mean the trigger is consistent and of normal pull weight. When I put a loaded magazine in to actually shoot, the pull weight can vary from normal (like in dry fire) and on the verge of squeezing with all my might to get the trigger to break. It does break every time. When I check the grip safety, it disengages approximately 3/16" prior to being fully depressed. I have had two other people live fire the weapon as well that also had a difficult time with it, which also keeps me from thinking its the grip safety. I am going back to the range tomorrow, so I will tie it down and run a mag through to confirm.

Again, thanks for your help with all this.

[Poppa Bear]

A couple of things. One, is your over travel screw backed off far enough? Had one a couple of weeks ago that was set too tight. He could fire fine when empty but could not get it to fire once a mag was inserted. He had ZERO over travel once the hammer fell, so there was no reset. Two are your pins even? I had a 1911 that was inconsistent in its trigger pull. Turned out the pins had a slight taper so things did not reset consistently. Sometimes the hammer and sear engagement was way off. Put in some straight pins and the trigger pull steadied down to a consistent 3 lb 7 oz.

[pyrrhic3gun]

There was another post a while back where the guy couldn't get the trigger to reset properly. The gun was just dirty. Have you taken it apart completely and cleaned it lately?

I had some crazy stuff happen when the trigger bow broke on mine a few years ago.

When you dry fire do you use empty mags? Make sure you try all your mags...maybe one is messed up, like you thought.

[benny hill]

Trigger bow is hitting the loaded mags. Try dry fireing it with a loaded mag in it.

[mwinter501]

A couple of things. One, is your over travel screw backed off far enough? Had one a couple of weeks ago that was set too tight. He could fire fine when empty but could not get it to fire once a mag was inserted. He had ZERO over travel once the hammer fell, so there was no reset. Two are your pins even? I had a 1911 that was inconsistent in its trigger pull. Turned out the pins had a slight taper so things did not reset consistently. Sometimes the hammer and sear engagement was way off. Put in some straight pins and the trigger pull steadied down to a consistent 3 lb 7 oz.

The over travel screw is what I figured was causing it. The allen wrench supplied with the gun was a little small and wasn't able turn the screw without rounding out, so I took the trigger out when I got home and used the proper size key to back it out. I have no idea about the pins, Ill have to mic those when I get home to check for a taper. Thanks for the help.

There was another post a while back where the guy couldn't get the trigger to reset properly. The gun was just dirty. Have you taken it apart completely and cleaned it lately?

I had some crazy stuff happen when the trigger bow broke on mine a few years ago.

When you dry fire do you use empty mags? Make sure you try all your mags...maybe one is messed up, like you thought.

The gun is still pretty new. I did take it all apart when I bought it and cleaned and re-lubed everything. I had dry fired with the one mag i had and the trigger pull was consistent. I'm having a hell of a time finding more mags for this gun right now because of the gun scare. I bought it to eventually carry on duty, but I'm going to have to find mags first.

Trigger bow is hitting the loaded mags. Try dry fireing it with a loaded mag in it.

Last night I took the trigger out and was able to back the over travel screw out a some. I put the frame back to gether and dry fired with a loaded mag. I probably dry fired about 10 times and then would strip one round out of the mag and dry fire it more for each round stripped until it was empty. I didn't have any problems then...every trigger pull was crisp and consisent. I brought it with me to work again today and will run a few more mags through it at our range.

Thanks, everyone, for the help. I will update the post this evening with today's range results.

[mwinter501]

Range was occupado today, so Ill have to wait until tomorrow. Thanks again for the help, Ill be sure to keep the post updated.

[Bunsen]

Make up some dummy rounds and try to dry fire it with a loaded mag then rack the slide and feel for the reset.

This will tell you if the trigger is resetting correctly or it is a bad trigger bow.

[mwinter501]

Make up some dummy rounds and try to dry fire it with a loaded mag then rack the slide and feel for the reset.

This will tell you if the trigger is resetting correctly or it is a bad trigger bow.

The reset has always been fine during dry fire. Still saving funds to get started with reloading, so I cant make up any dummy rounds. Hopefully everything goes well at the range today. Thanks for the help!

[mwinter501]

Range Report:

Only had time to run a few mags through today, but everything ran great. Smooth, crisp, CONSISTENT trigger pull and absolutely no problems.

I bought this weapon because I am a 1911 lover who has the opportunity to carry one on duty. As everyone knows here, if you run a 1911 for any extended period of time, you will get very proficient at mag changes. Not wanting to pause during a gun fight unless absolutely possible, but still wanting the same manual of arms I'm used to, I decided to drop the coin on the STI Tactical knowing it may have a lot of growing pains before I could get it to be reliable. Outside of the over travel screw being a little too deep, there has been no problems what so ever. I even lucked out and caught Midway USA while they had 45 mags in stock yesterday. I have a lot more rounds to run through her and a Gunsite 250 class before she'll go with me to the streets, but I'm really happy right now.

Thanks to everyone who weighed in on the problem, I really appreciate it.

Edited March 22, 2013 by mwinter501

[Poppa Bear]

My search fu is lacking because I am doing this on my phone. Look up Brazos function check? It will tell you the proper procedure to check hammer sear over travel settings. It will keep you from destroying your sear/ hammer hooks.

Edited March 23, 2013 by Poppa Bear

[mwinter501]

My search fu is lacking because I am doing this on my phone. Look up Brazos function check? It will tell you the proper procedure to check hammer sear over travel settings. It will keep you from destroying your sear/ hammer hooks.

Thank you so much for telling me about this article. I just read it and it was probably the best explanation of how all the trigger parts work together. Here is the link in case someone wants to read it.

http://www.brazoscustom.com/magart/0407.htm

[JKSNIPER]

Have you disassembled and cleaned it?

Sometimes ghak (technical term from gunsmiths) is left in the weapon from initial assembly at the factory. I've seen metal shavings come out in first cleanings of some weapons. Not a usual occurrence but because it happened I never bring a gun to the range until AFTER I've cleaned it first.

Helps to avoid some problems.

FInd a friend who reloads or talk to one of the guys at the range. I'm sure any reloader there would have NO problem making up dummy rounds for you to work with.