Selector Switch Location

[M1tommygun]

My other post was accidently sent into cyberspace, so I am re-asking the question. I want to install a dummy selector switch on my M1sbr, but I need to know exactly where I need to install it. This will be for looks only, not a bolt hold open. I also need to know if there are any modifications to the internal parts so the switch will not come in contact with them. Thanks.

 

A big thanks to adlake for the parts I needed.

 

Scott

[reconbob]

The center of the rocker pivot hole is 2.585" from the front

face of the trigger frame, and 0.550" from the surface above

the front pivot plate hole - i.e. the lower step at the front.

The large dia. is 0.301 +0.0025" the small dia. is 0.181 +0.0025".

This is from US Ord Dwg #D6535511 Dec 1941.

 

Bob

[M1tommygun]

Thanks reconbob. I will use this as a template for the job.

 

Scott

[deerslayer]

the sear, pawl and disconnector will all hit the selector. You will have to remove material from all three to get it in place.

[M1tommygun]

Thanks deerslayer. I was wondering, if I turned the shaft of the selector switch down would I still need to remove material from the three peices you mentioned?

 

reconbob, is there a website I can look at the drawing you mentioned?

 

Thanks,

Scott

[deerslayer]

The sear needs almost the radius of the selector notched out of it. The disconnector needs almost a full diameter out of it, and the pawl needs about a radius. Easier to just remove metal from those parts.

 

There is a picture of the print in Tracies Hills book. If you don't find it, I can email a picture.

Dan

[M1tommygun]

Thanks deerslayer. I do not have a copy of Tracy Hill's book. Is it on a web site anywhere? Of course, you may have to email it to me. Many thanks for that.

 

Just curious, when I radius the three parts, it will not affect the function of the rifle? I guess I need to get the parts, disassemble the rifle and see what you are talking about.

 

Scott

[brian]

QUOTE (M1tommygun @ Jun 12 2007, 01:34 PM)

Just curious, when I radius the three parts, it will not affect the function of the rifle? I guess I need to get the parts, disassemble the rifle and see what you are talking about. Scott

you'll need to make a new a pawl spring.

 

doug richardson's semi-auto thompson book/pamlet has a pretty good write up on this subject, complete with drawings of the modified parts.

Edited June 16, 2007 by brian

[deerslayer]

Forgot that part. The spring on the pawl comes down in the middle of the selector. You can move the little pin over that holds the spring in place but cutting it off flush and wire welding a new peg a little to the rear. Then you can drill a little hole for the other end of the spring to locate from.

[M1tommygun]

Thanks for all the help guys. I was able to install the dummy selector with out having to modify the pawl or spring location. I used the dimensions provided by reconbob with a minor location change due to the new pivot plate. In had to grind out clearance slots in the sear and the disconnector, but not the pawl. I did turn down the selector shaft and this helped with clearance. I did not want the bolt hold open option, just the ability to move the switch from full-auto to single like it's full-auto brothers. I have not had the chance to see how it functions on the range, but everything seems to function as before, but with a new outside appearance. Where I work we have two laser engravers, so I used one of them to mark the full-auto / single markings on the receiver. I do think I engraved the full-auto a little low, but other than that I am pleased with the results. I will try to take some pictures in a couple of days, if anybody is interested. Again, thanks for the help.

 

Scott

[M1tommygun]

Here are some links to photos of this project.

 

Selector switch and engraving :

http://i27.photobucket.com/albums/c164/m1t.../Picture005.jpg

http://i27.photobucket.com/albums/c164/m1t.../Picture004.jpg

http://i27.photobucket.com/albums/c164/m1t.../Picture006.jpg

http://i27.photobucket.com/albums/c164/m1t.../Picture002.jpg

 

Scott

[Chromebolt]

Looks good. http://www.machinegunbooks.com/forums/invboard1_1_2/upload/html/emoticons/tongue.gif

[Zamm]

M1tommygun,

That engraving looks pretty good.

Do you guys have a Yag Laser?

I work with a couple of CO2 lasers, but they don't cut metal, only remove finish from metal like Parkerizing.

Drives me crazy sometimes. They will easily cut off your finger, but just bounce off metal!

Zamm

[Norm]

Good job!

[M1tommygun]

Thanks for the good words guys. I wish it actaully switched to full auto, but it is just about where I want this semi-auto to be.

 

Zamm, where I work we have two NDYAG lasers. I have played around with them some over time. They will definitely mark the metal with what you want, including 3D marking. From what I understand about these lasers they will not cut your finger off, but they "tatoo" you bones if you are not careful.

 

Scott