Wednesday, January 5, 2011

A Spare Magazine for an Aeron B96 Part 1

Nervous about posting part one before the mag is finished. There's still so much that can go wrong--and if it all goes down in flames, I'm not likely to tackle this again until I buy a proper milling machine.

Been looking around on the usual airgun classifieds, gunbroker, ebay...looking for a spare mag for my Aeron B96. They just aren't out there. Apparently, none of the importers ever had spare mags in any kind of quantity, either. The gun came with one single-shot and one five-shot mag. Gotta tell ya, when this gun comes out to play, 5 shots lasts about 2 seconds. In a perfect world, I'd have five or six spare magazines for this gun--OK, sure, I'd probably have ten. As I have to do this manually, I'm going to attempt to make exactly one.

How precise does the mag need to be to function correctly? That's my biggest concern. If the mag body isn't square, or the holes not the exact diameter, or parallel, or the height is off... I don't know if I have five thou of leeway or none. Will it shave lead off the pellets as they jump to the breech? Will it leak CO2?

The mag holds five .177 cal pellets and fits into a carrier on the pistol. The carrier indexes the magazine for each shot. The mag is just along for the ride.

Cut a piece of scrap aluminum to approximately the same length.

Set up the milling attachment and squared the milling vise.

For a change of pace, I used a homemade fly cutter instead of an end mill .

The fly cutter holds a lathe knife at an angle and swings it through an arc. The edge just skims across the work leaving a nice, flat surface in it's wake.

All I wanted for the first step was a flat side. The fly cutter did it in one pass.

I turned the piece around and zeroed the opposite side. My hope was that the fly cut side would make for an accurate base when milling the magazine to final width. There's a 1/4" HSS blank tool bit in the vise as a parallel--needed some stand off, otherwise the surface to be cut would be recessed in the jaws.

Milled the piece to 0.273"--the width of the mag.

Rotated the piece 90 degrees fly cut the face, then milled the opposite side, making the piece 0.280" in height.

A bit of clean up on the edges and corners then the ends were milled square to a final OAL of 1.687"

I guess part one should've just been titled: "Derrick makes an aluminum rectangle". Give me a few days, I'll let you know how it goes.


Anonymous said...

What ever happened to the Benji 30/30. The last entry I saw was end of October. Did you tire of it or was it a bust?


Fred S.

Felice Luftschein said...

I ran out of enthusiasm as well as 8 gram CO2 cartrdiges. It works, it just doesn't work well and I'm not sure that it could be made to work well given the condition. Maybe I'll return to it.

Anonymous said...

I'm not surprised you lost interest in the Benji 30/30.I hate saying this, but bb guns are boy's toys. No way I would have quit on a bb gun that is reputed to have super powers!


Anonymous said...

i found three of those mags in a tin of pellets i bought at a car boot sale.


Anonymous said...

they have these in stock and other parts for the aerons at

Nick Hulme said...

May Of London no longer list the BRNO mag but Magic 9 Design Ltd does,