Diamondback Ejector Rod Thread size

[Xringshooter]

I tried a search but couldn't come up with anything. Brownells couldn't help me either. I need to know the thread size of the ejector rod. A client was doing his own work (duh!), took the ejector rod head off and ended up messing up the first couple of threads on the rod. It's a LH thread but I don't know the size (to get a die to clean it up).

Anyone here that can help me out? Thanks.

[retiredgunsmith]

I have only been working on Colt revolver since 1948...never saw one with left handed threads on the ejector rod.
This must be some wierd variation of the Diamondback.
If right handed, most wee 4/40 thread.
( I have some new old stock 4/40 thread ejector rod heads.)

[A1A]

Try a known 4-40 screw in the head.

[Xringshooter]

I'll look at it again, but it didn't look like right handed threads to me.

This Diamondback was made in 1967 according to the serial number. The part that is messed up is the end of the ejector rod, where the knurled end screws on. The ejector rod on the Diamondback is a one piece rod which is held in place (along with the spring) by the crane bushing. It is not 4-40, thats too small, a 6-40 is too big I already tried. It appears to be closer to a 5-40.

I'm out of town right now so I can't look at again until Friday night. If I get the chance I'll get a close up pic of it and post it.

[dfariswheel]

Colt never used left hand threads on any DA revolver, at least not as made after 1908, and most especially not on a post-WWII revolver like the Diamondback.
If it has left hand threads, god knows what someone has done to it.

Sorry, I can't remember what the new style threads were or when the change was made to the newer style, but I think the change was made before the Diamondback.
The old style Colt ejector rod head thread was 6/36.

[Xringshooter]

From the answers I've received it probably isn't a LH thread. That was my original thought because the threads at the end were so messed up (this was a replacement part from Numrich). If I can determine the size then I can rethread it correctly. I'm going to call Colt today when I have a chance to see what they tell me.