Welrod - How to make.

[Snoop-Uk]

Contemplating making a Welrod outta a springer a tracer shell(hopefully one no one would miss)

 

Whats peoples thoughts, practical for airsofting?

[Deinhardt]

this guy did a pretty epic job out of one of those Marui "Gindan" PPK/s 

[teflon don]

im actually building one right now

im using a mk1 as a base gun 

my initial plan was that to modify it so i could cock it and fire it single action but after disassemble and a lot of head scratching i have decided to keep it double action  

[renegadecow]

I've made KJW MK1 single action conversions before. Not exactly fun as it involved fabricating a new trigger bar that works as a sear plus modifying the charging handle.

[teflon don]

do you have technical drawings of the new trigger bar and sear or do you perhaps have pictures of it ?  

[renegadecow]

Unfortunately I don't as those were from a time when I didn't have a decent camera. I do however have a Mk1 at hand which I could take pictures of and illustrate how to do the mod. You can actually just mod the original trigger bar, but I opted to make a new one so as to make it reversible. The mods on the faux bolt however are pretty much permanent.

[teflon don]

 

 I do however have a Mk1 at hand which I could take pictures of and illustrate how to do the mod. You can actually just mod the original trigger bar,

 

that would be awesome 

im thinking about using the welrod that im building for the building contest so i want to make it perfect 

[ninja master of coffee]

I'm intrigued, does the mod give the Mk1 a lighter trigger pull? It's pretty heavy as standard, I'm vaguely thinking of creating some kind of very quiet pistol and that would seem like a good option.

[renegadecow]

I'll get around to it by tomorrow. Basically when you pull on the bolt it pulls back on the hammer and at the same time pushes the trigger bar. The gun is then pre-chambered and depending on how deep you make the sear to be can vary the trigger pull weight from .5lb-2lb.

[ninja master of coffee]

Oh nice! Cheers dude, need to pick up a Mk1 some time now

[renegadecow]

Alright, so here's how I did the single action only mod. Disregard the mainspring housing under the trigger bar as I only used it to prop things up.

 

Firstly, the drawings below do not represent true dimensions but a rough illustration of the alteration required. Like I said it's possible to simply modify the existing trigger bar by adding material to it, but making a new one would be advisable as it allows you to swap things back to original spec.

 

The red area on the bolt needs to be cut away allowing it to move backwards.

 

Below shows the sequence of charging the weapon with the position of the hammer relative to the modified/fabricated trigger bar. The red line represents the added material while the red dot is painted over a nub which is no longer needed if you fabricate a new trigger bar and likely will need to be ground off if you modify the existing one.

 

Bolt pulled back, hammer pushes forward on the trigger bar which chambers a round.

 

Hammer is pulled back enough to clear the lower ledge of the trigger bar which then lodges against the higher ledge which is effectively a sear. The length of the higher ledge will dictate length of trigger travel while its angle relative to the nub will reflect on pull weight. A zero angle tangent to the nub will be the lightest provided the surfaces are polished and lubricated. Setting it at a slight incline against the nub will mean having to resist the hammer tension first before the trigger bar clears allowing the hammer to fall. Do not set it at an incline in the direction of the nub as this can mean a dangerously light hair trigger as the hammer tension itself assists in pushing the trigger bar out of the way. 

 

Trigger is pulled along with the trigger bar and the higher ledge (sear) clears the nub on the hammer allowing it to fall.

 

Also notice that the bottom of the trigger bar has to be built up. Normally the trigger bar is allowed vertical movement as a mechanism involved in releasing the hammer in double action. On the single action trigger bar you want it stationary so you either build up material on the ledge in the frame where the trigger bar sits or you build up on the trigger bar itself. As I can't provide the actual dimension to recreate the single action sear, it would be advisable to make a prototype as I did before by making a plastic version of it first. It won't last long, but it's enough to get the dimensions down by trial and error before making one out of metal. It's also possible to make the trigger bar out of plastic and merely reinforcing the contact points against the hammer nub with sheet metal.

[teflon don]

thanx RC you rule, 

just one small question 

if i would want to ad material to that trigger bar how would i do that 

bondo will wear out to fast and i guess solder wont hold, will epoxy work ? 

[renegadecow]

It's pretty thin so I'm guessing sheet metal and steel epoxy sandwich would work or you could TIG/MIG/Lumiweld chunks of aluminum on it then reshape it after.