Thread: Help with 6-40 Countersunk UNF screws

These appear to be a little like hen's teeth to source. I'm after 3 only 3/8" or longer.

Can anyone help?

Please flick me a PM if you can.
Thanks

Easy peasy - workshopinnovation.co.nz

Look in the gunsmithing section

Originally Posted by NZ_noddy

These appear to be a little like hen's teeth to source. I'm after 3 only 3/8" or longer.

Can anyone help?

Please flick me a PM if you can.
Thanks

Are you sure about the size @NZ_noddy?

6-48 and 8-40 are the old scope mount sizes

6-40 is fairly common for rings and rails, probably more so than 6-48

both are available at workshopinnovation

they also sell taps - good idea to clean out the threads on tiny stuff like this, but you need to make VERY sure of the thread specs...

I'm definite about the size.
@ebf they don't have csk in 6-40 otherwise would have got them from Robert :-(

@NZ_noddy The oval head ones have a conical bearing surface.

https://www.workshopinnovation.co.nz...rewsSocketHead

You can get those in 1/4 or 3/8 lengths. And the bonus is they are not slotted - I HATE slotted screws

Thanks. Worth a try so I've ordered some.

Thanks for your help.