Help! Miroku disaster!

[perklo]

So one of my wife's coworkers has this old Miroku Japanese .38 special that he had polished the last of the old blueing off and insisted that he would be fine with a cold blue job. Tried to talk him out of it but you know .

Wasn't really locking up right but he swears it still worked.

After I sprayed gun cleaner in it and soaked in acetone to degrease and went to work.

Sprayed wads of oil back into the mechanisms but now won't cock at all. No smiths locally want to touch this thing. I have lots of semi auto experiance but no revolver knowledge. Anybody work on these guns?

Thanks -perklo

 

[Dave DeLaurant]

You've got your work cut out for you! This was marketed under the economy EIG banner at a very low cost. The reason no smith wants to work on something in this class is that it is hard to find parts, and even harder to guarantee it will stay fixed.

Miroku's own branded revolvers are a considerable step up in quality. They are supposed to be loosely based on one of the Colt DA lockworks, but I wouldn't swear to it having never seen one. Maybe this one is too. If you could carefully remove the sideplate and photograph the lockwork, someone here may be able to diagnose your immediate problem.

 

[JohnKSa]

I'm not really familiar with the internals of that gun.

Does everything work in DA? If you pull the trigger without cocking the hammer first, does the hammer go back and then drop?

If so, then it's probably one of these things.

The spring that tensions the sear is stuck or damaged.
The hammer notch is full of crud so the sear can't catch it.
The hammer notch or the sear are damaged/broken.

There's one more possibility. Are you sure that it cocked originally? I believe some of these guns may have come in a double-action only configuration where the hammer could not be cocked.

 

[perklo]

Yes, when I got it it would cock and rotate in both DA and SA mode. However, I noticed it would not lock the cylinder in place after fully cocking hammer. Now after applying the cold blue, rinsing it off and flooding inside and out with Remoil it won't cock at all.

 

[Mizar]

Applying Cold Blue without full disassembly is asking for trouble... Disassemble that poor revolver and clean it.

 

[trackskippy]

...... rinsing it off and flooding inside and out with Remoil it won't cock at all.

You want "drops" not floods here. If you arent going to take it apart and clean it, Id flush the insides with Gun Scrubber until it runs clear, shake it out and give it a minute to evaporate, and then put a couple of drops in at the trigger and hammer.

I agree with Mizar too, disassemble it and clean and lube it properly.

 

[trackskippy]

Just had a quick look over at Numrich/Gun Parts and it looks like they have a lot of parts for them, should you need them.

 

[wcwhitey]

Open it up and spray brake cleaner in it, that will flow the crud out. Without disassembling the internal parts flush it and blow it out. Then see. Sounds like a dried up grease and oil situation. It’s a start without taking a deep dive but the side plate is going to have to come off.

 

[Dave DeLaurant]

Just had a quick look over at Numrich/Gun Parts and it looks like they have a lot of parts for them, should you need them.

Well spotted, but be advised that when I did some image searching on the Miroku 38 revolver I found a version with a somewhat different lockwork featuring a coil mainspring instead of the flat mainspring in the OP's photo:



Numrich also mentions two different types of hammer. If the OP reaches the replacement parts stage, I'd make sure they match those in the Numrich photo before ordering.

BTW, does the cylinder latch move freely? Some revolvers are designed to lock the hammer if the cylinder latch isn't fully in the locked position.

 

[perklo]

This has flat mainspring. I'm going to tear into it soon. See if it's part damage or crud jam.

 

[Monac]

I have had one of these EIG Mirokus for a few years. I took the sideplate off. Once. I will never do it again. You know what I found?

1) There are parts mounted on the inner side of the side plate that must be carefully aligned with parts on the inside of the gun for the trigger mechanism to work and for the sideplate to go back on. It was a headache to get the thing back on. I am not referring to just the cylinder latch; there is something else in the sideplate that meshes with the trigger mechanism. They are different internally from the Colt Police Positive Third Issue revolvers they are externally copies of.

2) The hammer on mine was NOT attached to the mainspring, which is the spring that powers the hammer in order to fire the gun, among other things. It was not designed to be attached, as far as I could tell. The mainspring simply extends into a quarter-inch gap in bottom of the hammer. If you dry-fire the (empty!) gun double-action, you can see the hammer bounce back and forth a bit. That is unique in my experience. I would not call it good.

3) The EIG Mirokus have plastic grips. The revolvers that Miroku sold under its own name had nice wooden grips. A pair of those turned up cheap on Ebay, so I bought them. Although the two guns are visually identical, the wooden grips do NOT fit the EIG. I can think of no explanation for this other than spite.

I agree competely with Dave DeLaurant above; the revolvers Miroku sold under its own name seem considerably better made than the ones they sold via EIG. And parts do not seem to be interchangeable betwen the two, even though they both use the "Special Police" model name. And they probably have no parts in common with the type Dave DeLaurant shows in post #9, which is Miroku's "Liberty Chief" model. It is quite different from either version of their "Special Police".

In short, these guns are of some interest to collectors of obscure revolvers, but as shooters they have nothing going for them unless they are already in good working order. I got mine back together, and although I thought I had lost the spring that powers the cylinder latch, that seems to work fine. (For once, I have the gun right here at my computer.) There is pretty much nothing to lose by trying to fix it, and you may learn some things about gun repair, but it may not be fun.

PS - I just took the plastic grips off my EIG Miroku. Notice how in pertko's (the OP) gun the flat mainspring is attched to the inner side of the grip frame by a screw? Mine is the same way...except on mine, that screw is about one inch further down the grip frame, and the mainspring is correspondingly longer. Also the sideplate on mine is a much tighter fit than the one on pertko's. That may be due to the buffing job, of course. Good luck with that thing!

 

[Mizar]

The problem is, that Perklo is trying to completely re-blue the revolver with Cold Blue, without disassembly. And Cold Blue is one of the best ways to provoke rust, especially in hard to reach areas - screws, sideplate corners... They can be effectively ceased in place by rust and that is not a really good thing. Not to mention, that he already has mechanical problems and I strongly suspect that at least a part of them comes from Cold Blue entering the action and not being effectively cleaned up.

 

[Tallball]

I think mine is different. Here's the picture, in case it might be useful.

Miroku 38 special

• Tallball
• Oct 4, 2018

 

[Monac]

I think mine is different. Here's the picture, in case it might be useful.

Miroku 38 special

• Tallball
• Oct 4, 2018

That appears to be a Miroku "Special Police" sold under the Miroku name and not under the EIG name. I think otherwise it is like pertko's. Like Delaurent says, it is more nicely made than the EIGs, and is in much better condition as well. It has the wooden grips you see on the Miroku Special Police guns, and is bigger than the Liberty Chief model. Ever had the sideplate off? (If not, please don't do it on my account.)

PS - I am sorry I have been misspelling your username all through this, perklo.

 

[Tallball]

The finish looks better in person. It seems to be a decent revolver. The chambers are a bit tight, but it works fine with factory ammo. The size is pretty much the same as my 2" Model 10. The trigger and accuracy are good. IIRC, I bought it because it cost almost nothing.

I've never had the sideplate off. Thanks for the warnings about that.

 

[gary711]

View attachment 1125296


So one of my wife's coworkers has this old Miroku Japanese .38 special that he had polished the last of the old blueing off and insisted that he would be fine with a cold blue job. Tried to talk him out of it but you know .

Wasn't really locking up right but he swears it still worked.

After I sprayed gun cleaner in it and soaked in acetone to degrease and went to work.

Sprayed wads of oil back into the mechanisms but now won't cock at all. No smiths locally want to touch this thing. I have lots of semi auto experiance but no revolver knowledge. Anybody work on these guns?

Thanks -perklo

I inherited a Miroku Liberty Chief 38 special 2" I am partially disabled & can't make it to a gun range to test it out. I asked around here who could work on it to make sure it works, and was given this info for this gun "I had mine refurbished and new parts made by Eric with Helix gunsmith services in Missouri, shoots like new" I did talk with Eric, but could not get to a dealer that would ship it to him. I did however connected with a police officer who took it out to the range for me and shot 24 rounds both DA & SA. He said it worked great, he cleaned it for me and lubricated what he could get at. Said it is vert accurate & nice to shoot. Heres a few photos.

 

[4v50 Gary]

Applying Cold Blue without full disassembly is asking for trouble... Disassemble that poor revolver and clean it.

Absolutely.

The problem is, that Perklo is trying to completely re-blue the revolver with Cold Blue, without disassembly. And Cold Blue is one of the best ways to provoke rust, especially in hard to reach areas - screws, sideplate corners... They can be effectively ceased in place by rust and that is not a really good thing. Not to mention, that he already has mechanical problems and I strongly suspect that at least a part of them comes from Cold Blue entering the action and not being effectively cleaned up.

Thorough cleaning and flushing. The bluing action must be arrested.

The bolt/cylinder stop works exactly like that on a S&W revolver. As the trigger nose dip, it pulls the bolt shelf down; causing the bolt to lower and disengage the cylinder notch. This allows the hand (which sits on the tail of the trigger) to engage the ratchet and begin the rotation. Slightly before this point where hand pawl completes rotating the the cylinder, the trigger nose slips off the bolt shelf. Freed, the bolt acts under pressure of its spring pushes the bolt/cylinder stop back up and through the window. It is thus in position to intercept the cylinder notch and arrest the rotation. Finally the hammer mounted sear disengages the trigger. Pressure from the hammer spring pushes the hammer forward and gun goes bang.