FA bolt blocker - help the new guy

[PortHolio]

looking for suggestions on the best or easiest method for blocking the full auto bolts. I'm building a BRP kit, and it came with a pretty elaborately machined "blocker bar".

It looks like I'm supposed to machine out a stepped slot in the receiver, (problem#1 = I was dumb enough to start building a SA MG42 without a mill), but this looks like it's going to take out all pre located rivet holes.

I see other builds where guys just weld in a chunk of bolt or something pretty simple, and that's the way I'm leaning

Thanks, C

[oakrodent]

Mill out the correct hole for the semi auto block. I have done a few BRP receivers. I have a step by step build of one here on the site.

Good Luck

[johnnymg]

PortHolio, if you are not going to use the BRP blocker I would like to purchase it from you if you do not use it.
Johnnymg

looking for suggestions on the best or easiest method for blocking the full auto bolts. I'm building a BRP kit, and it came with a pretty elaborately machined "blocker bar".

It looks like I'm supposed to machine out a stepped slot in the receiver, (problem#1 = I was dumb enough to start building a SA MG42 without a mill), but this looks like it's going to take out all pre located rivet holes.

I see other builds where guys just weld in a chunk of bolt or something pretty simple, and that's the way I'm leaning

Thanks, C

[Michael J]

Those of us who have re-welded their receiver rears have used old drill bits or drill rod to block the FA lug on the bottom of the bolt from entering. While you could machine out something fancy, this method is easier.

Although it is an old method i learned from Pirates old tutorial, anyone know if it is still "valid"?

[Bil]

As long as it prevents a Full-auto bolt from being inserted,it should be fine.I used a hardened bolt.It has to stick up enough to block an unmodified bolt,and not be easily removed.As to Canada specs,you are on your own up there! ---bil

[Michael J]

Unfortunately we don't have any known specs ... Aside from marstar having created 2 mg42 prototypes (in which are very different mechanically than this build), i am literally pioneering this. Once i'm done, i'll have literally the only m53 in canada, and the 3rd mg42-looking semi auto in canada that is not prohibited by law . Assuming the cops approve the design, but i have heard they have not been so understanding with paramilitary semi-auto's...


Hardened bolt though, never thought of that! I went and asked my shop teacher if i could have one of his old worn out drill bits, that worked good enough .

Didn't mention this, but the benefit of the bolt or drill bit is no machining to be done, just need a steady hand or drill press. I'm trying to think of other round objects you should be able to buy at a local hardware store, but nothing comes to mind right now...

How about you dremel-cut out the slot for the BRP blocker? I mean, it doesn't have to be too pretty if you are welding over the area anyways i think?

[bolex]

I would use the BRP bolt blocker. The other methods would work, but the "factory" method is a little more "offical" looking. The dremel method will work well, just take your time and good luck.

[rocco1911]

The hardened blocking pin is used in several different current designs & is accepted as well