Morini CM84E accidentally discharging

[Nev C]

Recently my CM84E has started to discharge on closing the loading lever. It has never done this before and I am wondering what the cause is.
It did this three times today in a club match and I resorted to switching the trigger off while loading to prevent it discharging.
Ammunition was SK Standard plus.
Has anyone else experienced this?

[deadeyedick]

Sounds like the sear setting is too fine.

[Nev C]

I may have found the reason.
I removed the action from the grip to have a close look at the workings and found that the infra red receiver had rotated and was not receiving the light beam from the emitter.
This would have the same effect as having a finger on the trigger as far as the safety was concerned.
I'll glue the receiver in place at the correct angle and test it at the range next time.
Top photo shows the correct angle of the IR receiver and the bottom photo shows the elevated angle as I found it.

[Gwhite]

Nice bit of detective work. Thanks for sharing that.

I will add that to my files.

[conradin]

I have this happened to me before, and I cleaned the pistol and the problem was solved. But I will certainly look into your solution if something happens again on my CM84E. Thanks.

[Gwhite]

This happened to me today in a match. I had closed the action for the first shot of my second record target, and was about to lift the pistol when "bang". I have a witness that my finger was no where near the trigger.

I've had this pistol for about 20 years, and never had a problem. It has at least 10 thousand rounds through it, and close to that many dry fires.

It didn't do it again for the remainder of the match. When I got it home, I checked the optical sensor, and although it had rotated up a bit, I couldn't get the trigger to fire the solenoid without blocking the light path.

I typically dry fire at least once or twice before starting a record series. I do this with the cocking lever fully up (learned from shooting a Hammerli 160), and the first one always goes fine. If I don't remember to fully re-cock the mechanism, often the second dry fire will trip the striker release and the cocking ear on the striker will fly forward and knock the cocking lever forward & down. I don't always remember to fully re-cock the mechanism before I start live firing.

I'm still not clear on what happened, but I'm guessing that I dry fired and didn't re-cock. Dry firing clearly jars the sear system enough that a 2nd dry fire will release the striker. I suspect I dry fired once, which almost tripped the sear, and then it let go several seconds later.

I've been studying the mechanism, and searching old posts on the proper dry fire procedure. There's nothing in the manual. It looks like whacking the cocking lever with the striker cocking ear can break it over time, so I clearly need to avoid that. As long as my pistol doesn't release the striker on the first dry fire, I should be OK as long as I ALWAYS fully re-cock the breech block before the next shot, whether it is live or dry.

The other option is to put a fired case in the action and close it fully. I do that so I can de-cock the pistol before storing it. However, I frequently have a hard time getting a fired case into the Morini chamber easily. I then remembered a trick someone recommended from teaching basic pistol classes. These plastic expansion anchors make PERFECT (cheap) .22 dummy rounds:

https://www.amazon.com/Hillman-Group-37 ... B000H5WVCS



I just tried a couple in the Morini, and they work great. They go in easily, and eject with enthusiasm. There is a little dimple in the rim from the firing pin hit. They are a lot softer than a brass, but should still provide some cushioning to the striker. The certainly hold up much better than the orange hard plastic dummy rounds you can buy (at great expense).

[David M]

I typically dry fire at least once or twice before starting a record series. I do this with the cocking lever fully up (learned from shooting a Hammerli 160), and the first one always goes fine. If I don't remember to fully re-cock the mechanism, often the second dry fire will trip the striker release and the cocking ear on the striker will fly forward and knock the cocking lever forward & down. I don't always remember to fully re-cock the mechanism before I start live firing.

I'm still not clear on what happened, but I'm guessing that I dry fired and didn't re-cock. Dry firing clearly jars the sear system enough that a 2nd dry fire will release the striker. I suspect I dry fired once, which almost tripped the sear, and then it let go several seconds later.

Dry firing the Morini 84e with the breech open is a sure way of breaking the firing pin.
Firing with the breech open will break the lug off the firing as the breech slams closed. The solenoid is not intended to release the sear with the breech open.
The Morini 84e can be dry fired on a empty chamber, the taper on the firing pin will not allow the pin to hit the barrel.
So no need to use a plastic dry firing plug.

The sear is not adjustable but can become worn or dirty causing a discharge on closing.
The main reason for a discharge on closing is a light set trigger (less than 50g) and a safety circuit not working.
Test your safety circuit by cocking a empty gun, do not put your finger in the trigger, do not break the safety circuit, but touch it on the side to move it aft.
If the trigger fires then the safety circuit is NOT working.
If not working then a repair is required, do not shoot without the safety circuit if trigger weight is under about 100g.
Better still get it fixed....

[Gwhite]

Dry firing the Morini 84e with the breech open is a sure way of breaking the firing pin.
Firing with the breech open will break the lug off the firing as the breech slams closed. The solenoid is not intended to release the sear with the breech open.
The Morini 84e can be dry fired on a empty chamber, the taper on the firing pin will not allow the pin to hit the barrel.
So no need to use a plastic dry firing plug.

The sear is not adjustable but can become worn or dirty causing a discharge on closing.
The main reason for a discharge on closing is a light set trigger (less than 50g) and a safety circuit not working.
Test your safety circuit by cocking a empty gun, do not put your finger in the trigger, do not break the safety circuit, but touch it on the side to move it aft.
If the trigger fires then the safety circuit is NOT working.
If not working then a repair is required, do not shoot without the safety circuit if trigger weight is under about 100g.
Better still get it fixed....

Fortunately, my safety circuit appears to work just fine, even with the sensor pointed up at a good angle. I'm still concerned that a lot of dry firing without any cushioning may be hard on the striker/breech block, but at least with most free pistols, you only have to do it once at the beginning of a dry fire session. The one downside of the plastic plugs is that they are so loose they tend to eject with a lot of enthusiasm & go flying. At least now I understand the mechanism a bit better, and can avoid any further risk of damage.

[SamEEE]

Friend of mine had the same issue and it was the optoelectronic module that was not behaving. It was alright so long as he didn't close it too hard.
Got it fixed up by Morini at a WC.

[PaulT]

I concur with all David M has posted.

In addition, you should not have to rely upon the “safety circuit” the pistol should not fire when closing the breach or during the aiming process except when the trigger is operated.
Users of the Morini 84e 2-stage trigger will recall their pistols do not have this installed.

One possible reason is dirt, usually from un-burnt powder from ammunition accumulating in the trigger mechanism that prevent the full return of the trigger into the “rest” position. Newer triggers have been seen to be supplied with a thin membrane taped over the top of the trigger unit to prevent this accumulation as access to cleaning this area is particularly problematic!

I use electrical tape over this area that is replaced on each cleaning of the pistol.

[Gwhite]

<snip>
One possible reason is dirt, usually from un-burnt powder from ammunition accumulating in the trigger mechanism that prevent the full return of the trigger into the “rest” position. Newer triggers have been seen to be supplied with a thin membrane taped over the top of the trigger unit to prevent this accumulation as access to cleaning this area is particularly problematic!

I use electrical tape over this area that is replaced on each cleaning of the pistol.

The next time you go in there, I'd be interested in a photo of how/where this is done. Mine is old enough that I doubt it has the tape, but I haven't been inside it in quite a while.

Thanks!

[PaulT]

<snip>
One possible reason is dirt, usually from un-burnt powder from ammunition accumulating in the trigger mechanism that prevent the full return of the trigger into the “rest” position. Newer triggers have been seen to be supplied with a thin membrane taped over the top of the trigger unit to prevent this accumulation as access to cleaning this area is particularly problematic!

I use electrical tape over this area that is replaced on each cleaning of the pistol.

The next time you go in there, I'd be interested in a photo of how/where this is done. Mine is old enough that I doubt it has the tape, but I haven't been inside it in quite a while.

Thanks!

If somebody could please send me link to reminder of how to post pic on this forum, I shall.

Importantly, this solution also sorts a MAJOR issue with the Match Guns MG5e where powder residue accumulates in the rocker part of the trigger mechanism preventing the return of the trigger to the parked position. Once powered up, the MatchGun MG5e electronic trigger is by default on and the breaking of the circuit when the trigger is operated causes the shot to be fired. So unprotected, this accumulation can prevents the return and recharge of the trigger leaving it in a state where the trigger can not function at all or discharge during the aiming process.

[David Levene]

If somebody could please send me link to reminder of how to post pic on this forum, I shall.

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