The OP's Colt:


That's a fine one!

I see it's s/n 879586. If you are persistent and lucky you can find an Ithaca bearing that number.

Here is a page from Charles W. Clawson's monumental work:




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Don't feel bad if you can't find that Ithaca.

I have Colt #944350.




According to Clawson, there is also a Remington Rand bearing that number. I haven't found it.

If you have a close look at mine, you will see it came off the line before the "crossed cannons" final inspection ordnance mark came into use. Clawson says that mark was adopted in October 1942 and appears on Colt pistols "after roughly serial number 830000." (See page 93.) Like other manufacturers, the serial numbers weren't all produced in order. Mine is earlier than the initial use of that stamp, even though it is a higher number than Clawson's "rough" cutoff.

Yours is a very nice find!

Curly