Trapdoor Rifles

Tom, I got ahold of some 4-40 x .125" set screws. They start but they won't thread in all the way and I don't want to force anything. What size are the screws that you are using? Ken, Thanks for the info but I would rather use a hex drive screw rather than the slotted versions shown on Numrich....

Greetings!

I was wondering if anyone knows the size of the set screw in the trapdoor cam lock.

I always tighten the screw after each session but this time it was not there to tighten.

Thanks in advance.
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