RGG Drum Magazine - Improvements?

[brk]

I have worked on the RGG drum magazine for quite some time.  I found two major items that seemed to caused me problems that I think I have overcome.  So I thought I would put what I did out there for others to get ideas.  Feedback welcome.

 

First, I had problems with the pins on the barrel plate jamming with the pins on the feed wheel. I think they were too short. I got my pins protruding from the barrel plate by .135\".  The original RGG plans that had drum mags showed a height of .1.  For these longer pins I had to create some clearance cuts on the frame and in the magazine well.  Here are some photos and a video.  The pins on the feed wheel are still on a .750\" B.C.  I think if they were on a .80 BC, it would work just a little better.  I do need to make a latch for the hinged mag well.  Anybody that has done this and would like to share how they did it is appreciated.

 

 

[brk]

Second issue that I had is getting Long Rifle to feed through the feed wheel.  It would feed shorts pretty well, but LR would jam. I made a feed lip on the in-feed side that causes the rim to be pushed up into the feed wheel.  The way the path of the bullets are, they do not go through the center of the feed wheel, but have to \"come up\" to enter the slot of the feed wheel.  I had seen with Cutter\'s different drum mags, that his bullet look to pass into the center of his feed wheel and then are carried out to drop into the pan. I have been kind of married to this drum and want to try to get it working.  So I made something that would tend to push the rim up into the slot of the feed wheel.

 

The first feed lip seemed to get the bullets into the slot of the feed wheel, but then some bullets would \"pass through\" and jam up on the opposite side.  So I made a lip on the exit side to \"scope\" the bullet out and drop into the pan. This worked most of the time, but found I needed a second lip toward the center. So I added a slot in the feed wheel and added another lip on the inside of the drum on the exit side. Hopefully the pictures will do a better job of showing what was done.

[brk]

Here is a video with hand turning the feed wheel, the bullets seem to drop out well and not get jammed up. The initial part of the video is me trying to turn the feed wheel with my left hand while holding the camera with my right.

[brk]

One more item I need to address is a latch for the drum magazine cover. I don\'t like the \"bent over jewelry box\" latch with the RGG plans.  Anybody done something different?  I got some ideas but not happy with any of them.

 

I hope to see some replies and suggestions on what others have done.

[Cutter]

I have never seen a RG-G designed drum magazine

in working condition. I visited Paul several years ago and he was

having trouble with the one he has. The model in my video was as far

as I went with the design. So, you are far ahead of where my progress ended.

I did make an adjustable feed wheel to set timing,

 

I will be following your build and wish you great success.

Very nice work brk

[Dave]

Following along...

 

Nice work!

[brk]

I machined my bolts for the extractors from Gbull and found a little interference with the drum and the feed lips I made.  Before the extractors were in the bolts, the bolts all cleared the magazine and feed lips, but with them installed, there was just a little interference. I missed this when I drew up the feed lips.  The magazine would have needed just a little clearance with or without the feed lips. I had to put a small radial (or arc) cut in the lower 1/16\" sheet brass cover of the magazine and then add a 1/16\" x 1/16\" relief in the feed lips.  I could have gotten by with less clearance, but did not want to do it twice and figured a little extra clearance here wouldn\'t hurt anything.

 

Extractors from GBull were very accurate to each other but were a little off from the .dxf file. I did have some extractors from Cutter from years ago when I bought the bolts  and forgotten I had them (actually I had misplaced them).  Cutter\'s matched the dxf but varied a little more than Gbulls.  Gbulls didn\'t vary more than about .001\"  He said he had them wire EDM, Cutter\'s were milled.  I checked them out on a optical comparator I made a dummy bolt and made a few samples on the cuts/cross hole for the extractors. If I put the cross hole on location for the heel of the extractors, Gbulls extractors were about .067\" from the face of the bolt to the underside of the extractor.  Cutters were much closer to .055\".  I decided to move the cross hole toward the rear and used Gbulls since his were already hardened.  I figure I could use Cutter\'s as spares and may just need to take a little material off the heel to get those to the.055\" from face of the bolt to underside of extractor.  This way gave me the most options with extractors from two sources.

 

I advise anybody that is going to fit extractors, make a dummy bolt first to get the setup right and tweak to get what you want. I had a total of 23 bolts and got them all machined without scrapping any.

 

Here are some pics

[Sparky_NY]

That is some fine looking workmanship right there !