COMPLETED--- AT M-1939 in 4" Kosdon case

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Dave A

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I bought this Kosdon case, never been used. It's a thick-walled 3/16" case so the OD of it is slightly larger than other cases. My plan is get into EX when I slow down but for now, Aerotech's 98mm M-1939 in this 12,000n case.

TOP: 4" x 36.75" x 0.1875" Kosdon case

ROW 2: Aerotech 98mm, 4g liner

ROW 3: AT Stainless Seal disk-------AT Nozzle, 98mm CTI nozzle holder, Custom nozzle washer, Snap Ring

ROW 4: Snap Ring, Custom 1" spacer, CTI Grain Spacer, Custom 1/4" hardened adapeter washer for "Hub Cap", CTI Pro75 Adapter "Hub Cap", CTI 98mm Fwd closure

Note: The CTI Grain Spacer can be removed for a 5 grain reload or add an extra for a 3 grain reload.
I wanted to keep the machining to a minimum because I had to "farm" that out. The custom spacer and hardened washer I found on McMaster-Carr. Very little turning was needed for the custom AL spacer. That adapter washer ID was perfect fit to go over the "hubcap" however my buddy's small lathe could barely cut the OD. I made a jig from a saw arbor, spun it on the big drill press and spent 30 minutes grinding down the edge only 0.125"
 

Attachments

  • M1939- Kosdon.jpg
    M1939- Kosdon.jpg
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  • 4 in & Hubcap.jpg
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  • M1939-Kosdon Fwd Assy.jpg
    M1939-Kosdon Fwd Assy.jpg
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  • M1939- Kosdon  Aft assy.jpg
    M1939- Kosdon Aft assy.jpg
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