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Mcarbo spring kit

PostPosted: Fri May 10, 2019 12:17 am
by Xtratoy
Just sent this to Mcarbo regarding their trigger spring kit.
I just installed you RM380 trigger kit. As sent your spring actually increased the pull weight. I measured the springs for diameter and length before installing. My Trigger pull stock was at 7 lb 2oz. After installing just the trigger spring weight went up to 7lb 6 oz. Measured with Lyman digital gauge. I then replaced OEM trigger spring and used your hammer spring and got 7lb 5oz. Both springs were longer than the OEM springs. Trigger spring was about 3/16" longer and hammer spring was .019" longer. Gun has been fired 18 timed since I bought new. After adjusting springs I ended up with around 6lb 10oz trigger pull. I didn't get the 2lb reduction your web site claimed .

Waiting to hear their response

Re: Mcarbo spring kit

PostPosted: Sat May 11, 2019 8:28 am
by Xtratoy
Image OEM spring on right , Mcarbo on left.I contacted Mcarbo and still nothing after 2 days.

Re: Mcarbo spring kit

PostPosted: Sat May 11, 2019 3:52 pm
by jth737
What was the adjustment process ? Are the M-Carbo springs now the same length or shorter than the originals ?

Re: Mcarbo spring kit

PostPosted: Mon May 13, 2019 6:53 am
by Xtratoy
Hammer spring ground to same length and trigger spring bent to mimic factory spring. I have received 2 emails from Mcarbo asking if I have received my parts with this message "We're all about Fast Shipping and I just wanted to make sure you got your parts? Please take a moment to verify you received everything and that nothing was damaged in transit.

If you still haven't received your package or you suspect there is an issue with your order send an email to help@mcarbo.com and we will get back to you ASAP " I still haven't heard back from them.

Re: Mcarbo spring kit

PostPosted: Tue May 14, 2019 4:25 pm
by mamaxwell
Sorry you had issues my kit was perfect. Easy install no issues.

Re: Mcarbo spring kit

PostPosted: Sat May 18, 2019 4:53 pm
by jth737
Just received and installed the M-Carbo trigger spring kit on my RM 380 with no problems. Noticable reduction in trigger pull and smoother break. Wish they'd offer a short stroke trigger bar.

Re: Mcarbo spring kit

PostPosted: Sun May 26, 2019 8:03 am
by Xtratoy
Mcarbo finally got in touch with me and exchanged spring kit. I still had to tweak what they sent me to achieve a trigger weight of 6 lb 4 oz. That is also including the FunFlyer hammer spring modification.
topic3075.html Still not the 2 pound reduction claimed for the spring kit. I also polished up the trigger bar everywhere it made contact with anything. In the future I will bend up a trigger return spring out of a smaller diameter wire and see if that changes much.

Re: Mcarbo spring kit

PostPosted: Mon Oct 14, 2019 9:32 am
by Walt Sherrill
Note: you can't compare the length of a spring that has been installed/used to a fresh one that hasn't been used for a comparable period.

Springs take a set, and the new trigger spring will do so, too. The differences in spring length is especially noticeable with recoil springs, but all springs will take a modest "set" with use. (It's understood by the folks to design or specify the springs, and some change is expected with use.)

Re: Mcarbo spring kit

PostPosted: Thu Jan 23, 2020 3:28 pm
by Walt Sherrill
jth737 wrote:Just received and installed the M-Carbo trigger spring kit on my RM 380 with no problems. Noticable reduction in trigger pull and smoother break. Wish they'd offer a short stroke trigger bar.


One of their kits includes new springs and a different trigger bar -- and the trigger bar does shorten the trigger pull a bit. (It's not what I'd call a short trigger, but it is an improvement.)

A short trigger may be possible, but that option would probably require a heavier hammer spring for the hammer to ignite primers.