Marushin M1911A1 Slide Lock Problem

Post by October

i got my caps today! these are really fun...even tried the magnesium powder trick. one problem i'm having is that on the last shot the slide is not staying locked open... and occasionally you pull the trigger and click, nothing. i think i'm loading the caps right but how would i know, i cant read japanese. mark, did you say you had a marushin govt. m1911a1? have you experienced any of these things? any suggestions? i need to get more shells! i cant wait to fire the mgc i have ordered...

Post by Mark

Hi october,

Yes, I do have both a Marushin Combat Commander HW and a Government model ABS (center fire) And two earlier Government model kits (side fire)

Ok, the slide stop malfunction is common due, mostly to friction and spring pressures. Does the slide lock in the open position when the empty magazine is in place and the slide is actuated by hand?

If not, then the magazine follower needs adjustment or, the slide isn't being blown-back far enough to be caught by the slide stop on the last round.

With the empty magazine in place, pull the slide back slowly past the slide stop notch.

How far past the slide stop does the notch go? If the slide stops or the spring pressure becomes hard just before the slide stop notch, then some adjustment is needed.

The slide stop malfunction is a common problem on modelguns even the Japanese modelgun experts have problems with this.

I have had very little problems with my Marushin Colt Combat Commander and the slide stop seems to work ok but, my example was a kit version that I was able to tune.

Just observe the pictures and do as the instruction "say" via the pictures..

Post by October

its hard to say if the tension gets harder before the notch, but yes the catch works by hand, just not when firing the last shot. what kind of adjustments can be made?

Post by Mark

Well, you can check the slide stop for burrs and check for any binding that maybe present in the slide stop hole. Also, you might put a little oil on the slide stop shaft to reduce any friction.

The slide should go a little bit past the slide stop before stopping due to spring pressure and the slide hitting the frame. If the slide stops just before the slide stop notch, well..Plastic needs to be removed from a few places.

My Combat Commander was like your government model at first, as my slide didn't remain open after the last shot. So I tinkered with it and it has worked since.

Post by October

well, the stop is going past the notch. it almost seems as though the slide is not getting pushed back enough, i did have it catch once. this was after i put some silicone oil (airsoft oil?) on the o-rings in the shells, and in the slide grooves. i also worked the slide open & closed repeatedly to try and spread the oil around inside. it almost seems like the more i play with it the more it gets loosened up. like what i said about the clip not coming out smoothly, well it comes out a little further than before. maybe the whole thing will get a little more "broken in" as i play w/ it and get the parts moving around... still doesnt lock open yet though.

Post by Mark

Alright! there is the key to your problem...friction..When you put the silicone oil on the O-ring you eliminated the power robbing friction that occurs when the cap fires.

When the cap fires, the expanding gasses force both the "piston" (with the O-ring) and the detonator thats pushing against it and since they are immoble as the detonator is attached to the barrel, the gas pressure then is redirected towards the cartridge case and since the case and the slide are movable the slide and cartridge move rearwards.

Now, if the O-ring is installed dry, there is the added friction as the O-ring friction has to be over come by the gas pressure.

If the friction is too much, the slide may not travel far enough back to catch after the last shot is fired..

Post by October

so it is as simple as oiling the o-rings?

Post by Mark

Yes, oiling the O-rings can help but, it could still be some other problem..

You might try oiling the O-rings and seeing if the slide stays open on the last shot.

If so, then the problem was insufficient gas pressure. If not, then something else is the problem.

Post by October

yes... when i reassemble the cartridges, putting a drop of oil on each o-ring, the slide stays open on the last shot... it also seems like the shells dont hold all the crud from from firing the cap, so they are easier to clean...

Post by Mark

Hey that's alright! I am glad that that worked out for you! If the friction is reduced in these modelguns, they work far better they wear less and they are easier to clean.