Suomi Drum / M11 (RO) Conversion

[tyromeo55]

I need to redo my tower again. It's about 1/8" too short and won't lock in to the magwell. This is starting to get old.

Better add 1/4'' to be safe... I'm wanting to see someone get theirs running 100%

[fathergoat]

not much luck with mine either

[strobro32]

Are you guys using the cabled or uncabled dummy rounds?

[medphys]

Are you guys using the cabled or uncabled dummy rounds?

Not there yet. I've just been using live ammo. Once (if) I get it running, I'll figure out what to do with the dummy rounds.

[strobro32]

Your not going to believe this but the problem turned out to be the tray on one of the drums was rubbing on the lower feed tab. I cleaned it up and I have mega spring strength now. I just hand stripped 140 rounds!

I'm ready for a live fire test.




medphy, those dummy rounds can save a lot of weight for the spring force.

[medphys]

Your not going to believe this but the problem turned out to be the tray on one of the drums was rubbing on the lower feed tab. I cleaned it up and I have mega spring strength now. I just hand stripped 140 rounds!

I'm ready for a live fire test.




medphy, those dummy rounds can save a lot of weight for the spring force.

How's your thumb?

Thanks on the dummy round hint too. Never thought of that.

[strobro32]

My thumb is fine. I just open the back and load it like a regular Suomi drum.

I better post some pics in case it blows up in my face. I want them to know what I was working on.

[strobro32]

I'm wondering if I should fully weld it up before I test? It is heavy loaded and I would hate to have if fall apart at the range. The tack welds are beefy and might hold.

On the other hand, if I weld it up and something is wrong, I would probably destroy the tower getting it apart to tweak it.

[strobro32]

No test fire tonight.

It looks like I'm taking it apart. I had stoppages for 4 out of the last 5 attempts to strip rounds by hand. I need to work out a new internal "mixing ramp?" The idea to go quickly and directly from two streams of rounds into one looks promising. I think it helps combines the power of both springs force into one row. It also got my dummy round count to 18.

It seemed to feed strongly without the plastic strips lining the drum but I'm going to include them anyway.

Man this was a good project. I'm learning a lot.

[Nate7667]

Damn nice work Matt.
Hope you get that thing running.

[medphys]

I had stoppages for 4 out of the last 5 attempts to strip rounds by hand.

Seems to be par for the course.

I disassembled mine tonight and rough cut the tower extension. Everything is ready for shaping and welding the tower back together (hopefully) tomorrow. Then I need to make another internal magazine spacer before I tack weld it all back together. Since this should be the final assembly, I can take my time and try to make it look a bit more presentable. My welding leaves much to be desired (weld, wire brush, weld, cut off porcupines, weld, grind, wire brush, repeat...)

[strobro32]

Thanks Nate for the well wishes. We need all the positive thinking we can get.

I know the drill medphys. I don't own a welder. I have to drive 22 minutes each way across town to tig. Yesterday I did that trip 3 times. All of this work is done by files, glass paper and a rotary tool. I can see MrM4 rolling his eyes right now.

I think I nailed the new mixing ramp. It only a paper pattern now but tomorrow I fab it and weld it in.

[medphys]

I know the drill medphys. I don't own a welder. I have to drive 22 minutes each way across town to tig. Yesterday I did that trip 3 times. All of this work is done by files, glass paper and a rotary tool. I can see MrM4 rolling his eyes right now.

No kidding, but I'm sure there are others.

At least you can tig weld. I've got a Craftsman flux core wire welder that seems to have 2 settings:

1) won't penetrate the top of the drum

or

2) burns through the magazine

[Jmacken37]

You guys are studs. Matt, if I promise NOT to drive next UT, can I try your drum?

Vegas...you didn't even shoot that cool as all get out Lage upper and your already collecting drums and coffin mags???

Jake

[strobro32]

Anything for you Jake. Just don't do to the drum what you did to Richards prototype.

Thanks again for loaning me use your extra modified Suomi mags for my 1st SMG shoot.

[MrM4]

Matt make sure you make Jake shoot a full drum, not just 5 rounds.....

[MrM4]

Thanks Nate for the well wishes. We need all the positive thinking we can get.

I know the drill medphys. I don't own a welder. I have to drive 22 minutes each way across town to tig. Yesterday I did that trip 3 times. All of this work is done by files, glass paper and a rotary tool. I can see MrM4 rolling his eyes right now.

I think I nailed the new mixing ramp. It only a paper pattern now but tomorrow I fab it and weld it in.

AKA : Demil Tool?

[Jmacken37]

SCREW YOU, MATT (that applies to the both of you!)

Jake

[strobro32]

I can feel the love. I can't give Jake to much grief, after all, I did break your M16 Matt.

My new mixing ramp is a thing of beauty. It was the most complicated aspect so far. Many compound angles to figure. I tested it clamped into the tower and it works well. I will have it welded in and the drum tacked together tonight.

[greenpeas]

I've been looking at doing a drum conversion for some time now. I finally broke down and ordered a couple of drums from Centerfire yesterday. I probably won't start cutting and welding until this fall - too damn hot out there!

I run modified Madsen mags in my M11/9. They are high quality magazines. Madsens work great and this is what C&S used for their drum towers. C&S still has a bunch of these mags left. I just ordered some more for $20 each. (not a bad deal for a good quality steel mag for the M/11) It's an easy conversion to make these run in an M11/9.

From what I understand the height of the tower is directly proportional to the frustration factor in getting these things to run.

Great thread guys!