Atlas Matched EGW Hammer/Sear

[Robertwil18]

Is there any reason to believe that a precision matched Atlas EGW hammer/sear would not work in an STI pistol?  Obviously given that the hammer pin hole is straight and properly aligned, these should simply be drop in replacement parts with MINOR (if any) fitting needed, correct?   

[HIREDgun45]

When I've swapped ignition parts sometimes I had to work on the thumb safety to properly block the sear.  Tweaking the sear spring may also be needed.

[zzt]

I have used several kits from EGW.  They do not match them in any way.  They simply pull the parts out of the parts bins, drop them in a bag and call it a kit.  Every one of the kits dropped in and was usable as is, after adjusting the new sear spring.  That tells you how good there parts really are.  That being said, I'm anal about triggers.  So I polished everything and made sure everything had perfectly even engagement.  About 10 minutes with a super fine ceramic stone and everything that mattered was mirror bright, smooth and perfect.

 

I do not know what Atlas does to 'precision match' the EGW parts.  I do know that Brazos Custom, a custom builder and expert on STI pistols offers a trigger kit that he has reworked.  His kit is specifically set to drop into an STI pistol.  Many on these forums rave about how well they work after literally dropping them in.

 

Atlas uses PT frames (and a few JEMs) in his builds.  He builds great guns.  However, if I were going to bet, I'd say he makes sure they are perfect for perfect frames.  STI frames are not perfect, so Brazos tunes his for them.

 

The best thing you can do is talk to each and ask questions.  Explain your concerns and ask what the likelihood of a perfect fit is. 

 

BTW, the EGW sear has the least meat where the thumb safety engages it.  So if your existing sear is fatter, you will have to peen the TS and refit it.  I usually start with an EGW sear.  It the TS doesn't work I move up to an Extreme Engineering/Cylinder & Slide sear.  That is fatter where is counts and often will allow the TS to work without refitting.  Since a lot of people use EE parts, that often works.  In bad cases you can always go to a Harrison Custom sear.  They are the fattest I know of.  You will almost definitely have to remove some material from the TS.  BTW, you can order the Harrison Custom sear with a TrueRadius already on it.  That will allow you to drop it in and do nothing (except fit the TS) unless the hammer hooks are not evenly engaged,  That is super easy to address.

[HOGRIDER]

IMO, the Extreme Engineering Lite Speed Hammer along with the Ultra Low Mass Sear is as close to a professional drop in kit as any I have experienced!  The Wire EDM machining produces a mirror polished primary AND secondary angle on the sear along with a mirror finish on the hammer hooks.  There's also a debris channel provided on the base of the hammer hooks.  The sears I have used are usually .4045"-.4050" and have not required any modifications to the thumb safety.  I have seen the Residual Resistance of a 1911 style pistol drop from 16oz down to 6.6oz using nothing more that the EE hammer and sear. 

 

EGW and Harrison's sears are also averaging .404" and usually work well in STIs.  My Staccato P came with a .404" sear as did my Son's.

 

Another option for not having to replace the thumb safety is to purchase EGW's long sear (~.407") and stone the primary down to +.005" of your existing sear length using any of the available sear jigs.  My favorite is the Warner Precision True Radius Pro.

 

https://shop.harrisoncustom.com/hd-806-true-radius-pro-sear-stoning-jig

 

HTHs!