Friday, March 19, 2010

A New Crosman 22XX--Making a Hammer Part 2

Back to work.

Marked a line to locate the cocking pin hole.

Center drilled,

Drilled undersize

Brought the hole to 1/8" diameter.

And counterbored for the shoulder on the (as yet unmade) cocking pin.

Need to create some breech screw clearance in line with the cocking pin hole.

Started by filing a flat.

Then transferred to the Taig and ground a curve. Protected the ways with some foil to keep abrasive grit at bay. Cleaned the lathe bed thoroughly afterwards.

I'm still on the left.

A larger clearance area than the stock Crosman.

Hardened the face of the hammer. Hopefully correctly.

Polished it out again.

Skipped a step earlier and needed to reduce the OD to approximately 0.738" to achieve a sliding fit inside the gas tube. The front of the hammer laughed at the HSS lathe bit I tried first. A small carbide tipped cutter did the trick. The rear of the hammer is much softer. I was hoping for a differential hardening and it looks like it was achieved. I didn't remove all the machining marks on the body. My thought was the small grooves would hold and retain some lubrication. Blued the part with Birchwood Casey Perma Blue Paste.

Ah--almost forgot. I made the clearance area larger because the hammer was heavier than the Crosman. When finished, it was only 2 grams lighter than stock. Pretty close for winging it.

More parts to come.

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