I have a ca. 1972 Model 66 (original 66, not a 66-1,2,3 etc.) combat magnum that has a bulged chamber (hand-loading faux pas most likely). S&W no longer has replacement cylinders for that vintage. I called around for days but couldn't find anyone who could work on it. I managed to locate a new recessed cylinder/ejector combination from Numerich, but the center pin doesn't fit the new cylinder. It protrudes through the hub in the ratchet quite a bit further than the old one (~ 0.130 extra), which is beyond the ramp so you can't close the cylinder. Does anyone know if there was a change in dimension of the center pins between shoulder and end somewhere in the production run? My pin is 0.842" from shoulder to tip, but to fit would need to be 0.709" to match the original. All I can figure is the new ejector has the center pin stop bored deeper. Another curious observation it the hub in the center of the ratchet is of larger diameter on the replacement cylinder: 0.300" vs. 0.255 on the original part. It doesn't seem to affect function; the cylinder timing seems OK with the replacement, it's just the center pin is way too long.

Welcome aboard.

Yes, ctr pins have undergone changes thru the years.

If you trimmed the pin at the rear to proper length, will it still be long enough to disengage the extractor rod at the front locking bolt? If so, that's your easiest and best remedy.

If the milled groove in the recoil shield is wide and deep enough for the extractor star hub, should be a non-issue.

__________________
Jim
S&WCA #819

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