I am almost done with my Suomi M31 build but I may have a problem with the end cap and the pressure regulator.  Mine came with out the rubber piece which I assume has something to do with the pressure relief.  Does anyone know where to get one of these and will the gun work without it ?  I hope I have not posted this in the wrong Forum, I am a new member. Any help would be appreciated.  I am also looking for any manual or book on the maintenace of the Suomi M31 and  CZ 26.  I have manuals on all my guns except the CZ 26 and the Suomi M31.  Thanks

leroyjr11 wrote: I am almost done with my Suomi M31 build but I may have a problem with the end cap and the pressure regulator.  Mine came with out the rubber piece which I assume has something to do with the pressure relief.  Does anyone know where to get one of these and will the gun work without it ?

That regulator is only to slow the rate down on full auto, you shouldn't need it for a semi

This shows step one in the removal process. Center punch the rivets and drill with a 1/4 inch drill. Keep checking the hole, as you drill, and you will know when to stop. Use a heavy hammer and punch to knock the rivets loose. If at some point, you can grab the return spring with a pliers, pull the spring out. At the point the spring is out and the handle cab move freely but the sl*g is too large for the hole.

Tom

Grind the sl*g on the cocking rod end and pull out the handle. Finish punching the rivets out.

Tom

OK, dumb question here but with my receiver now soon to be on the way...I must ask.  What will need to be done with the 80% receiver to get it rolling?  Do the ejection port and magazine slot need to be cut?  If so, with what.  My old receiver provides a pretty good diagram for where the SN and both ejection and mags should fit.

 

What else will need to be done?  Looking ahead for tools and I need to start thinking about methods to fufill my madness...

 

thanks

Here's some pictures of the New "weld-on" front filler. These weld to the receiver in place of the front stub. (the front stub is used for mounting either an original filler or one that Numrich was selling)

These are 80% complete (just like the Numrich are only 80% complete). I have however "rough" shaped them to reduce the amount of grinding required to get to the finshed shape. The numrich fillers were square and required more grinding. You will however have to grind the curvature where the shroud twists into place. Holes are close to finish diameter, however you may need to do some final fitting to your parts.

I am talking to another Weaponeer member about having him fabricate these so that the demand (that I am sure is out there) can be filled faster, so don't be surprised if another member offers these up for sale.

 

Ace123: The new diameter is 1.170 for Mike's reduced diameter receiver. The bolt is 55Rc hardness. Turn them at high rpm with light cuts using carbide tools. The firing pin geometry is being out.

Tom

I've got a newbie question. When building tube guns like these, do the receivers need hardened once they are complete? If so whats the best method?

Depends on "who's" receiver you use and what they are made out of.

My receivers are built from 4130 chrome moly steel... They do not require any hardening as they are harder than the original.

They also have the "reduced" ID in the front section of the receiver like the original and have the ejector installed....

They are available in original & reduced (which I recommend for semi builds) ID's.

 

Wow look at my intact Suomi charging handle and filler that I received from centerfire today!

 this is a link for the front filler removal http://www.gunco.net/forums/showthread.php?t=20352&highl ight=disassembly

 

 

Edited by chris_us31

midwestnewbie wrote: can someone with an intact front filler give me a measurement from rear of barrel shroud locking recess to back edge of filler TIA

28mm  You're talking about the hole the locking lever goes in?  Or that notch in the front where the tab on the shroud locks in? 38.4mm


Edited by Shep

Jestims' front fillers still require a bit of milling.  If someone made some that were 100% complete that would be helpful.

The easiest way to get that filler out is to "drill" the pins out with a bit that is smaller than the pin.... this will allow the balance of the pin to be driven out without much effort...

C_Kassidy:

The way I got my pins out was to carefully drill the top of the pin and part of the structure around it. Try to get the drill bit centered on to the pin. I manged to drill most (not all) the support structure. I did this on both sides. The pins punched out easy. I figured that If I drilled a bit too much it would not really matter once I put the filler back into the new setup. I did the same thing for the stock tang.

For the bolt, I used a small punch to drive out the retaining pin. I then purchased a $3, very long and thin flat head screw driver. I removed the handle and the flat part of the driver to leave a round rod. I used my grinder to turn the diameter down on enough length of the rod so it would fit to get to the back of the firing pin and punch out the end. A couple of careful whacks and the pin came right out.

Hope that helps.

Maybe this will help you.

1st.... here are the dimensions from the 80% front filler's that Numrich was selling before they ran out.

Then here is a picture of a 80% "Weld-on" front filler.

And here is a picture of the 80% "Pin-on" front filler that will be available in the near future.

Yes.... I will be making an "adapter" for retrofitting any of my existing receivers to work with "Tommerr's" new barrel design. (once he has it ready). So anyone wanting to incorporate his design in to a receiver that has already been purchased will be able to......

Yes.... The AR fcg will require that the side rails be spaced out wider than the original lower width, which in turn will require some trimming of the inside of the stock the length of the lower and installing some shim material between the rear filler and rear tang and the lower rails.... I have considered milling lowers that would only be "wider" where the AR fcg goes, but that would just be another cost everyone would have towards the completion of the Suomi.... removing wood from the inside of the stock is cheaper....

I will be posting pictures and information on the Firing Pin in the next few days (time permiting)....

 

The front filler is held on by two rivets that have been smashed into countersunk holes in the two tabs that hang down from the front of the receiver. First center punch the two rivets. If you look close you will see them and the two tabs. I used about a 1/16 or 3/32 drill bit and drilled down 3/4 of the way through the pin. Then I used a larger bit, maybe 1/4" to take the countersunk head off of the rivet. Don't worry about drilling into the two receiver tabs since you won't be using them anyway. Then you take a punch that will fit down into the small hole you drilled and knock the two pins out. It shouldn't be too tough. Really very similar to drilling out the two rivets in the rear trunnion of an AK. One word of caution, make sure you don't drill clear through the pins with the small bit as it will make it a lot harder to punch them out. Hopefully this is easy to follow. Its not really very tough. I haven't removed the block at the rear of the receiver for the stock but it should work about the same.

Side plate prototype pictures... Don't mean to put the cart before the horse. For those who are not familiar with the process I provided a pic of the skeleton also. Once programmed I can punch a 4'x8' sheet in a matter of minutes.

My vision would be to produce for members for a small contribution to the site.