M*CARBO Brotherhood

Sig Sauer 938 Spring Kit

I recently took an “advanced CCW” class at my local indoor range and found that it was a blessing in disguise ! I went to it with the thought I could then go there as a regular and practice draw technique.
I took my then only 2 Sigs, 226 (.40S&W) and 938 to see how well I could draw and be accurate.

I learned much more than that !!! I learned how the 226 is real easy to get shots off from a draw/bang but the 938 was horrible! low/left with 5 inches off to the mark @7 yrd. It was a nice group (about3/4") so it showed me i had a consistent BAD technique. the trigger was SO stiff I felt like it took a Peterbuilt to nudge the trigger.
Upon getting home I ordered the MARBO P238/938 spring kit. Changed the way it feels ALOT !!!


You learned a valuable lesson that many don’t. It takes a consistent and proper grip to accurately shoot a handgun. However, that same grip doesn’t always translate to other handguns. Each model can have it’s own unique characteristics such as grip angle, length, trigger squeeze and recoil properties. You have to “learn” each gun. I have 2 Sigs, both 1911’s, but have been looking at the 938. Just noticed a couple of days ago that Mcarbo offers an aftermarket trigger for it. How much reduction in trigger weight would you say the Mcarbo trigger gives you?


THe only thing I have seen is the hammer and firing pin springs. Those I placed in the 938 Saturday evening.Combined they dropped it to 6 lb 2 oz average.
It is crisp but WAAAAAAY better than before and dry fire shows rock steady sight picture so I am looking forward to taking it the range and seeing how it shoots coming from, chest to fire, rapidly it works.

I am looking for a reduced main spring to bring the TP down some more but have not found one.


I don’t know if you recall the early days of the 938, but it was originally plagued with problems cycling 115g rounds. The Sig line was that it was set up for heavy for caliber rounds. I mention this 'cause you’ll need to be thorough testing after swapping out a main spring. The main spring actually has more impact on slide velocity than the recoil spring.

I think mine pulls somewhere 'round 6lbs and all I’ve done is shoot it. I didn’t realize M*CARBO does trigger bits. I’ll probably load up a cart tonight.


@Dane. no trigger parts for 938/238 hammer spring and firing pin spring. They changed the feel @ dry fire. I will see how it does next time to the range when I take my new M17 to pop it’s cherry.


I purchased the 938 in about 2014.
I do not know what the above quote really means . Does it mean the 938 was set up for 124gr. or heavier ?
I have had NO FTF or FTE issues.
At point and fire the gun runs just fine. The rapid draw and fire I experienced the low and to the left grouping in 2x tap drills.
I had taken 2 guns to the class and changed them at “break points” in the live fire segment.
When it came time for the single hand draw and fire portion of the class I had my 226 (.40) holstered.
The drill was to show how accurate (or not) we could be. 2 groups of 10 shots @10 yds., silhouette target 10 with right hand, change mag, 10 with left hand. My target had no head area left.

The instructor told me I was just showing off.

It was the only part of the target that was clear was my retort.


That was the claim. It sorta went away and later 938s have run 115s without issue. 2014 would likely be one of the earlier “fixed” examples.

Sounds like an enjoyable class as well.


It was !!! I took it thinking that I could, after successful completion be able to practice “Quick draw” at the range after completion of the course. Well as it turns out the range has no policy that that is the case. However that might change. We will see.
Now mind you I can se the liability to them if some YAHOO shoots someone doing QUIK DRAW on the range.

The blessing that came about in regards to the 938, and my ignorance of said issue, was what I am glad happened !!!
Discussion after the class is heading me towards going to a USPSA range and learning even more.