Saturday, March 29, 2008

Making a Barrel Band/Pivot Plug for the 1377, Part 1

Since I was bitten by the airgun bug, again, I've looked at all the wonderful modifications people have done to the simple Crosman 1377 pistol with awe. I figured a good first project would be the conversion the the 1377 to a small carbine. I ordered a steel breech and 24" barrel from Crosman (you have to call them to order parts), and bought the 1377 at our local BiMart.

The Steel Breech is an inexpensive upgrade.

You just take the pistol apart, and put it back together...

Add a shoulder stock (I bought two for the price of one through the online airgun classified pages)

The only modification to get to this point is to drill the barrel band/pump tube plug (part #1300A006) out to 7/16"

Pushing out the roll pin that retains the barrel band unit.

Just an ugly plastic part. The general idea of my project, overall, is to replace any plastic with metal.

I took some measurements and made some simple drawings. I decided a 3 part assembly would replace the one part unit.

Facing a length of aluminum rod.

Turning the diameter for the plug.

Filed and scotchbrite-ed.

I flipped it around and mounted it true in the 4 jaw chuck, then cut it off to length.

Turning a smaller diameter for the actual barrel band.

Drilling for a #10 screw thread.

Tapping with hand power, using the lathe for alignment.

Picking up the edge, so I can find the center line.

Picking up the end.

Spot drilling for the roll pin that retains it in the pump tube.

Drilling for the roll pin.

I then inserted a drill in the hole and rotated the unit 90 degrees, using the drill to magnify the angular position. While not a perfect technique, it's very quick and gets you spot on, generally.

At this point I had the vise snug but not tight and I pushed the plug all the way into the vise.
I milled the slot for the lever arm.

All done, except for deburring. You'll notice the groove in the plug. That's just an aesthetic groove...

Installed in the tube.

One part of three all done.

Part 2 to follow in a bit...

4 comments:

Roberto said...

Hey Nice work what kind of lathe is that. The plate in the back of the chuck looks like a front rotor disk with all the holes, like one on my 1000 yamaha virago.

Nick Carter said...

It's a Taig Lathe. The disc is an aftermarket index plate I make, it allows dividing work. It is handy if you have a spindle mounted on the cross or milling slide.

Robert said...

Will you be selling these if so how much, nice work. Thanks Robert

Nick Carter said...

I won't be making aftermarket parts any time soon, still learning the ins and outs of airgunsmithing. Maybe in a few years.