Screw size for Talley rings?

[EastHumboldt]

I’m swapping scopes between two rifles. The existing ring screws were loc-tited when the scopes were installed. I want to just use new screws rather than try to clean up the old ones. What size are the ring screws for Talley light weight alloy rings (Tikka). They kind of look like 6/32… but I’m thinking they might be 6/40. Anybody know for sure?

 

[Wapiti1]

If it's 32 threads per inch, count the threads in 1/4" of screw length and see if you get 8.

Jeremy

 

[EastHumboldt]

I like it. Good simple idea. Here’s my results.

The screws have 3/8” of thread. There’s 12 threads in 3/8”. 3/8”x 2.66667 = 1”.
12 threads x 2.667 = 32. A 6/40 screw would have 15 threads in 3/8” . The screws will thread easily into a 6/32 nut. So it really should be a 6/32 screw.

But…when I run a tap through the threaded hole in the ring, it doesn’t feel like I’m cleaning the thread. It feels like I’m cutting and I do get some metal shavings. Same when I run the screws into a 6/32 die. They go easily about 1/2 way through the die, and then the die starts cutting. Hmmmmm.