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False break point, Morini cm22

Posted: Mon Aug 23, 2021 4:37 pm
by VonKasta
Hello all, heres something for you gunsmiths to gander upon.
I recently came across a Morini cm22 with a really weird trigger, naturally I had to dig into it.
There was two issues, trigger was basically single stage, and once that was solved the new found pre stage was extremely gritty.
Let me first post a pic of the trigger unit so that I can explain better:
A453CA70-B333-4FB2-8285-A9FE972E8ACE.png
The mystery single stage trigger was due to someone removing steel ball no 11 (its supposed to control second stage trigger weight) from its location and instead placing it in between pre stage load spring 16 and pre stage adjust screw 15, together with a short (to short for comfort) sear engagement it held 1000g trigger weight but there was no pre stage, or rather there was only pre stage acting as single stage.
There was a very short false pre stage set witht the pre travel screw.

Anyway, once this was sorted, steel ball put back at its original position and everything adjusted there was a decent trigger, apart from the pre stage feeling very gritty and had a dead spot/false break just before second stage.
Upon inspection you could clearly see trigger bar 20 skipping into a groove as it engaged sear 7 into second stage.
This was what I found, probably worn from the bodged single stage attempt :
6C47F590-5807-4CA6-AA86-A38B95CE606A.jpeg
56C07E53-CB12-4F75-8490-A20DEBDFB10B.jpeg
So my question is, should the sear be looking like that (it seems hardened to me) oc is it just as worn out as the trigger bar? My feeling is that the harder sear has carved into the softer trigger bar but I can be mistaking. The sear isnt overly expensive, I just dont want to swap it our for no reason as its mated to the hammer at this point.

Re: False break point, Morini cm22

Posted: Mon Aug 23, 2021 5:47 pm
by Gwhite
Is the "catch" in the middle of the trigger pull, or near the end? If it's in the middle, you can probably polish it out. I've done this on a couple Benelli MP95's.

You don't want to round over the corners where the sear releases, so you set the trigger stop so it won't quite fire. Then, I use "Time Saver" #333n lapping compound on the rough area. If it's really bad, you may want to start with #111n, and increase the trigger stop so you are only lapping on the really rough area. Just keep moving the trigger back & forth. It has the advantage that it breaks down as it works, and (in theory), you don't even have to clean it out of the mechanism when you are done. I still try to get most of it out, but I don't get obsessive about it.

https://ws2coating.com/timesaver-lapping-compounds/

Re: False break point, Morini cm22

Posted: Mon Aug 23, 2021 6:02 pm
by VonKasta
Gwhite wrote: Mon Aug 23, 2021 5:47 pm Is the "catch" in the middle of the trigger pull, or near the end? If it's in the middle, you can probably polish it out. I've done this on a couple Benelli MP95's.

You don't want to round over the corners where the sear releases, so you set the trigger stop so it won't quite fire. Then, I use "Time Saver" #333n lapping compound on the rough area. If it's really bad, you may want to start with #111n, and increase the trigger stop so you are only lapping on the really rough area. Just keep moving the trigger back & forth. It has the advantage that it breaks down as it works, and (in theory), you don't even have to clean it out of the mechanism when you are done. I still try to get most of it out, but I don't get obsessive about it.

https://ws2coating.com/timesaver-lapping-compounds/
Thanks, that looks very interesting. Have you had any success using thease types of abrasives for sear/hammer engagement points as well or are they simply to hardened?
Should work like a charm smoothing out the trigger bar as it doesnt seem hardened at all, or it has worn through and its due for replacement anyway

Re: False break point, Morini cm22

Posted: Mon Aug 23, 2021 8:35 pm
by Gwhite
It was the sear hammer interface I was working on with the Benellis. The Time Saver in the green cans is for hard metal. You don't want to use it too close to the edges, because it will just round them over. I used it to remove roughness in the sliding portion of the trigger pull. In the Benellis, this was the first stage, but if you have a 2nd stage of any length, you can use it there as well.

Re: False break point, Morini cm22

Posted: Tue Aug 24, 2021 12:46 am
by VonKasta
Gwhite wrote: Mon Aug 23, 2021 8:35 pm It was the sear hammer interface I was working on with the Benellis. The Time Saver in the green cans is for hard metal. You don't want to use it too close to the edges, because it will just round them over. I used it to remove roughness in the sliding portion of the trigger pull. In the Benellis, this was the first stage, but if you have a 2nd stage of any length, you can use it there as well.
Very interesting, thank you

Re: False break point, Morini cm22

Posted: Tue Aug 24, 2021 1:23 am
by David M
It looks like the transfer bar (022097) and the sear bar (022089T) have been ground on purpose.
On the origional, the transfer bar notch is very square and straight.
Who ever did this may have been trying for a short travel single stage rapidfire style trigger with no
trigger slack.
I would replace both parts to return it to factory and set it up with a small clearance between the
transfer bar and sear (at full trigger forward travel) to allow for full transfer bar re-engage after
the slide cycles.

Re: False break point, Morini cm22

Posted: Tue Aug 24, 2021 3:38 am
by VonKasta
David M wrote: Tue Aug 24, 2021 1:23 am It looks like the transfer bar (022097) and the sear bar (022089T) have been ground on purpose.
On the origional, the transfer bar notch is very square and straight.
Who ever did this may have been trying for a short travel single stage rapidfire style trigger with no
trigger slack.
I would replace both parts to return it to factory and set it up with a small clearance between the
transfer bar and sear (at full trigger forward travel) to allow for full transfer bar re-engage after
the slide cycles.
Thanks for the input, yeah thats pretty much my conclusion as well. I have both parts on order so Im planning a full restore.
Pretty amazing that this level of bodge actually kinda worked, if all you care about is a short but crappy single stage that is.
Im picturing a guy used to single action revolvers that wanted to mimic the static trigger feel.

Re: False break point, Morini cm22

Posted: Tue Aug 24, 2021 5:00 am
by JamesHH
Don't know anything about the Morini sear, it sounds similar to the Pardini.

The Pardini sear requires a lot of engagement and everyone adjusts them wrong so the sear hangs on the tip like a revolver trigger so a flat spot wears and creates a false step.

Are Morini triggers supposed to be greased?

Re: False break point, Morini cm22

Posted: Tue Aug 24, 2021 5:33 am
by David M
On sears and sliding surfaces under pressure, Rocol Anti Scuffing paste works well..

Re: False break point, Morini cm22

Posted: Wed Aug 25, 2021 12:46 pm
by VonKasta
Thougnt Id give this one an update, the sear was the big culprit, after I replaced only the sear the first stage feels much better without even breaking it in. I will replace the trigger bar as well as its worn and I dont want to grind the new sear with the worn out trigger bar, but curiosity had me replacing them one by one to see the differance.
Heres a pic of the new sear, compare it to the old one above and its clear as day whats the issue.
A41552C3-BDD1-4812-8B48-C3D8CF7EF16B.jpeg