MP 18 Barrel Retaining Screw Question

[maxfaxdude]

I've got a friend who is looking for a picture an all-original MP 18 barrel retaining screw to do a rewat.  I've got an MP 18 (with pictures below) but I don't believe it's all-original and may be a rewat as well.   Can someone please post a photo of their MP 18 with a close up of an all original barrel retaining screw.   Thank you!  

[johnsonlmg41]

yes, that's a reactivation on yours and from pictures I've seen (when I needed to make one) have a different configuration.  Like  a fillister head, but IIRC slightly larger with no crown to it?   Been a while, but there are pics on the net of guns that have not been messed with original screws.   Normal deac, pull the barrel, weld it up, put it back in, replace the screw with weld and grind flat.  Not as bad as internally welding the barrel to the side of the tube, but I've seen that as well and it's harder to repair time wise.  HTH

[Rekraps]

I have one, let me look later today and see what the retaining screw/pin looks like. My gun is an original, all numbers matching gun (SN 35217).

[maxfaxdude]

7 hours ago, Rekraps said:

I have one, let me look later today and see what the retaining screw/pin looks like. My gun is an original, all numbers matching gun (SN 35217).

Thank you sir!

[Rekraps]

On 12/21/2024 at 3:26 PM, maxfaxdude said:

I've got a friend who is looking for a picture an all-original MP 18 barrel retaining screw to do a rewat.  I've got an MP 18 (with pictures below) but I don't believe it's all-original and may be a rewat as well.   Can someone please post a photo of their MP 18 with a close up of an all original barrel retaining screw.   Thank you!  

So here you go. I cannot comment on whether or not the barrel hold bolt you picture is original, however mine is. The bolt is finely machined with flat sides and a convex top. 

Edited January 25 by Rekraps

[StrangeRanger]

Max's screw is very different

Yours would probably be a"binding head machine screw"or a "pan head machine screw" (two variants of that, one flat-topped, the other convex) in US parlance.  I have had zero luck in finding out how that translates to the DIN standard; I'm bumping up against terminology with "machine screw." They must be called something else in Europe.  Can you measure the OD and height of the head and possibly the height of just the head sidewall and the slot width?  It may be necessary to repop one and dimensions work better than a picture

[Rekraps]

I'd be happy to do so. Give me a few days..... I am a little concerned about removing it as I am sure I would scar the bolt head. the slot is narrow. Lemme look at it and see....

[StrangeRanger]

You won't have to pull the screw.  If you're careful you can get all the external measurements except the sidewall height in situ with a caliper and with feeler gauges for the slot.  You can come "close enough for gov't work" to the sidewall height with a caliper

[Rekraps]

On 12/24/2024 at 11:22 AM, StrangeRanger said:

Max's screw is very different

Yours would probably be a"binding head machine screw"or a "pan head machine screw" (two variants of that, one flat-topped, the other convex) in US parlance.  I have had zero luck in finding out how that translates to the DIN standard; I'm bumping up against terminology with "machine screw." They must be called something else in Europe.  Can you measure the OD and height of the head and possibly the height of just the head sidewall and the slot width?  It may be necessary to repop one and dimensions work better than a picture

Well, as it turns out I was bored and the screw came right out with no issues. I took two pics (hard to get good pics of this part) and then measured the dimensions of the screw using my micrometer. Note that the screw seats into a very slight machined recess in the shroud. I think this was done to level the mating surface. 

Enjoy!

Edited January 25 by Rekraps

[StrangeRanger]

That covers it perfectly on behalf of Max and his friend many thanks

[Rekraps]

1 hour ago, StrangeRanger said:

That covers it perfectly on behalf of Max and his friend many thanks

You are welcome.  Anytime. 

[maxfaxdude]

You guys are awesome!

Rekraps...Thank you so much!

And StrangeRanger - thank you as well!

If you guys ever come to Vegas, I owe ya' a beer or 2!

Many, many thanks!!!!

[StrangeRanger]

Max,

Check your PMs

[Rekraps]

Screw thread at the head, .5cm dia tapering down to .45cm dia at the bottom of the thread. 

[hatrick]

Great job on the measurements of that screw!  That would be a good one to make some extras of since it’s very unique. I know I’d love to have a spare just in case.