I found out my friend has a Mig welder. And were goin to the S. FL build party to rivet our kits together, but we'd like to weld a milled kit to a receiver. After i saw that one thread where the guy welded the Russian underfolder together, i needed to do one. I was wondering if anyone had any info on welding it up. Like where to weld it at, through the holes in the receiver and any helpful info. Thanks!

Oh, where can i get a milled kit?

I weld reguler kits. You need to be a good weldor and have a good understanding of metalergy. You should have an oven in your shop and pre-heat everything before you weld. I'd say drill about a 3/8" hole for each weld, do a roset type weld. For a milled kit you have to (supposed to!) mill it down to the size of a trunnion. I'd clamp everything together and function check it before welding it (the point of no return) It really shouldn't be a problem IF your friend is a good/pro weldor.

you really have to be a better than avg welder
but it you wanna try take a large drill 3/8 or so and open all holes in rec up
then thransfer and drill about 1/16 in into the trunnion (rec stub)
then just weld it up

Ok, thanks. He's new to welding, but i still think it'd be fun to work on as a project.

first off, practice before you trash a kit.  

secondly, dont just open up the holes, what I do is cut out the space between the front trunnion top holes and weld one long bead right there, I then notch the lower holes to give me more area to weld to.  a bit overkill, but too little is never, ever enough.

Quoted: Ok, thanks. He's new to welding, but i still think it'd be fun to work on as a project.

I get pissed at guys who buy a MIG and think they can weld! I agree with socandyman, you must be an expert welder, I had about 12 years expieience before I welded an AK. Get some books (for your "friend") I sugjest books by Richerd Finch (HP Books, IIRC), he has welded all types of exotic metals, he has received recognition for his work on the space shuttle from NASA. I don't like MIG because the bead looks good even when it is not + you get "cold starts", when you start welding to quickly before you get a puddle going, I use a stick welder with 7018, that's what is used to make x-ray quality welds on nuclear reactors.

Agreed on all that...

I am a decent welder and I found the trunions on my Romanian and AMD kits to be a little strange to weld. I bought an extra trunion to sacrifice testing on before the real thing and was very glad I did. Guess the heat treat on them is more than I thought.

But a few thousand rounds through my weld-ups and I'm happy, though I have moved on to riveting them, it's much less work and looks cooler.

I agree with the advice above. Practice, test, learn, then do it.  A receiver blank is rather cheap if  it needs to be tossed so you can start over.

I welded up an AMD pistol and a Russian underfolder.  I have not put thousands of rounds thru them yet, but they seem solid so far with the many hundred rounds I've sent downrange.  I think welding is a simpler build process for certain situations, and takes less time than screw-building.  I do think, now that I have done several screw-builds and a couple weld builds, that I need to acquire more tools and try a rivet buid .  I am in it for the experience anyway, might as well try all 3.