Jump to content

MP18 vs MP28 barrel?


wwiifirearms
 Share

Recommended Posts

Does anyone know if an MP28 barrel will work in an MP18.I?

 

I'm looking into REWATing a registered DEWAT MP18.I. It is a challenging project for several reasons, but I see someone is making new MP28 barrels and I am wondering if they are the same.

Link to comment
Share on other sites

No, you cannot use an MP28 barrel in an MP18. They are completely different. In the MP18 the barrel is a little over 1/2" diameter over its length with the ends turned down for about 3/8" in front and maybe a bit more in the back. There is a bushing/flange inside the receiver at the rear that is held in by a screw a little below and in front of the magwell. Remove the screw and the bushing can be removed to the rear then the barrel will come out too. Its captured between the front bushing which if I recall is permanently attached to the receiver tube and the removable rear. It is a pretty simple barrel to make but the rear bushing and the screw that retain it are usually badly welded and difficult to remove on DeWats. I've repaired a number of them....

The MP28 barrel has a threaded flange at the muzzle which threads into the receiver tube. There is a lock screw at the top which keeps the barrel from unscrewing. The barrel has a flange at the rear which is integral to the barrel and keeps it centered in the receiver tube. I don't think I have drawings of the MP18 barrel...

Hope that helps

Frank

Edited by amafrank
Link to comment
Share on other sites

  • 6 months later...

No, you cannot use an MP28 barrel in an MP18. They are completely different. In the MP18 the barrel is a little over 1/2" diameter over its length with the ends turned down for about 3/8" in front and maybe a bit more in the back. There is a bushing/flange inside the receiver at the rear that is held in by a screw a little below and in front of the magwell. Remove the screw and the bushing can be removed to the rear then the barrel will come out too. Its captured between the front bushing which if I recall is permanently attached to the receiver tube and the removable rear. It is a pretty simple barrel to make but the rear bushing and the screw that retain it are usually badly welded and difficult to remove on DeWats. I've repaired a number of them....

The MP28 barrel has a threaded flange at the muzzle which threads into the receiver tube. There is a lock screw at the top which keeps the barrel from unscrewing. The barrel has a flange at the rear which is integral to the barrel and keeps it centered in the receiver tube. I don't think I have drawings of the MP18 barrel...

 

Hope that helps

 

Frank

Amafrank,

Hoping you can help. I got my Form 1 approved and started working on my mp-18.

I can't find any sign of a screw that would hold the rear barrel pushing in place that you mentioned in your previous post. Is it possible mine is held in place by some other method?

At present it is obviously held in place by weld, but before I start cutting I want to make sure I understand what is supposed to keep it in place.

http://i584.photobucket.com/albums/ss281/wwiifirearms/MP18/9D2C78D2-C026-46A0-B8B6-4583F3818588.jpg

http://i584.photobucket.com/albums/ss281/wwiifirearms/MP18/FADFEE36-5E6B-4DB2-A247-4EF74670CD1E.jpg

http://i584.photobucket.com/albums/ss281/wwiifirearms/MP18/10B9E37B-CAD6-46F9-BE20-2E8FA796C567.jpg

http://i584.photobucket.com/albums/ss281/wwiifirearms/MP18/592E4266-94EB-4F19-A2CA-F7F5BE1E061B.jpg

Link to comment
Share on other sites

I'm starting to think the screw that holds the rear barrel bushing was welded, ground, buffed, and blued. There is no sign of it today, but the area I expect it should be is heavily buffed.

Image I found online:

http://i192.photobucket.com/albums/z69/Quickload/German%20SMGs/BELOWMAG2.jpg

My gun:

http://i584.photobucket.com/albums/ss281/wwiifirearms/MP18/92179931-56B6-4F55-88CB-E16239ACF899.jpg

 

I assume I will need to locate and drill out the screw. If anyone can provide pictures or measurements relative to the magazine housing holes, that would be very helpful in locating the screw.

Edited by wwiifirearms
Link to comment
Share on other sites

Yes, the head of the screw has been welded over and then finished out to hide it. Having reactivated quite a few of these guns, my practice is to centerline between the two magwell screw holes and extend it forward about 3/4" past the forward edge of the forward screw hole. The center of the collar screw is approximately 11/16" from the center of the forward screw hole. This is not exact so you will have to drill a hole in that position about 15/16" into the body of the collar. Keep in mind that the weld will cover the head of the screw, usually more than the width of the screw head, and also penetrate into the collar. When the breech weld has been removed sufficiently that after impact against it to move it, a crack around the circumference can be seen, the screw weld might still be holding. In my experience, I have had to drive the loosened collar out with a large drift and hammer which then breaks the remaining weld holding the collar. The drilled hole has to be welded up and a new hole prepared for a new retaining screw, etc.

To remove the barrel, my technique is to grind through the breech weld around the seam between the breech face and the collar. The breech face is flush with the rear collar face. Usually it is possible to tell where is the original rear face of the collar by finding the small areas that were not reached by the arc rod. The weld will have to be removed at the seam a bit below the face of the breech and collar face to free the barrel. When the weld has been removed sufficiently to weaken the weld, you can drive the barrel forward out of the collar. With the ejector removed, and the front shroud cap removed, use a stout rod centered in the breech area and drive the barrel forward out of the collar.

Repair of the breech can be done to retain the original barrel and repair of the collar can be undertaken as well. MP18 barrels have significant markings on them that the owners like to retain, so preserving the barrel is always a priority.

Bolt face and firing pin tip are often damaged, too, so they might have to be dealt with.

Details will vary from the above but it describes some ways of dealing with the MP18 welding. Hope this helps.

Edited by Black River Militaria CII
Link to comment
Share on other sites

Awesome post Bob. It's cool to see all the photos and work that goes into the reactivation status. Bob (Black River Militaria) has my MP18i right now doing a reactivation. I'm patiently waiting to see and shoot the nearly 100 year old gun. I'm trying to find a Solothurn and/or MP28 now so I can work my way through history with the different guns.

Link to comment
Share on other sites

  • 4 years later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...