STI 2011 - Sear Spring Issue

[j28s]

Have a problem on STI 2011 9mm sear spring. The first leg (to sear) is popping off. I'll put the spring in, try a few trigger pulls and it works. Put it together, try about 5 more dry fires and the hammer starts following. Take it apart and see where the first let is off the sear. There is some wiggle room and didn't know if there was a trick or better sear spring that would help this. Thoughts?

[2MoreChains]

Take a look and see if the sear spring fits well into the little slot in the grip underneath the MSH. It could be that you have too much play in the slot, and that allows the sear spring to get mis-aligned.

Also check that your grip screws (the top ones) are snug. Any play between the grip and frame is not good.

If the two things above are not the cause, do you have another sear spring that you can try? They only cost about $8-10.

[jcc7x7]

You may need to put a small shim (piece of plastic) on the left side of the sear spring and under the MSH.

One of mine needed this to make the spring stay in place. That particular gun has not been taken apart much but it was the one that exhibited the same problems you stated in your first post.

[jstagn]

I have heard that people use pasters and business cards for shims, how long they hold up who knows..

[mcbutler]

SV Tri Glide sear spring will correct this issue.

[drewbeck]

If the slot is wallowed out you can fill and recut with ptex stick the same thing used to fill ski base damage. You could also fill and file as a permanent shim. Bottom line the spring is likely moving somehow and you just need to figure a way to make it stay in place consistently.

[Aircooled6racer]

Hello: Use a Dawson sear spring. The sear spring is bent over so it can't fall off the sear. Thanks, Eric

[jimbullet]

I am wondering what has caused this issue in the first place? I thought that they would have been manufactured in close tolerance. I am intrigued if this is something over time due to wear and tear?

[Supermoto]

Hello: Use a Dawson sear spring. The sear spring is bent over so it can't fall off the sear. Thanks, Eric

I tried a dawson spring on multiple guns, didn't solve the issue. The spring was shifting to the left and would fall the sear. I used a punch to peen the mainspring and then out a paster over the base

[sfinney]

The STI plastic grip has a slightly wider slot than most sear springs, allowing movement. Very common.

You can either peen the left side of the spring to make it slightly wider, or add a thin card between the spring and MSH, to exert more pressure on it from the MSH, helping to keep it from moving.

Or us an SV sear spring as they are made wider.

[Dustint21]

It must be the old grip style. The new 2011 grips have a little ridge to keep the spring from moving.

I tried to post a pic, but I do not have enough posts to attach links...

Edited August 8, 2014 by Dustint21

[troupe]

Plastic wears. Bedding compound will work great, if you know how to use it. A little dab will do ya !! SV springs will help also. Do be careful with the radius on the SV spring.