I'm going to replace the front bead on my field grade Browning Citori 20 ga with an ivory bead.

What is the thread pitch for the front bead?

Thanks.

It's funny what we take for granted when we have a vast array of shotgun sights sitting on a shelf next to the work bench. I replace shotgun beads regularly and yet I am unable to tell you with 100 percent certainty which size the Citori takes. If I had to bet, I would say 3x56. But again, I have all the other sizes and taps just in case.

Where you need a specific size, I would suggest unscrewing the bead and having a look before ordering. You're going to have to remove it anyway, so now would be a good time to do that. It's going to be either 3x56 or 6x48, but I'm pretty confident (99.1%) that it takes a 3x56.

on that topic-

I have an old "youth" model Marlin O/U 410 that needs a bead, what is the procedure for doing so once the right size is obtained?

thanks.

Screw in the new bead. Look to see how much the shank protrudes into the bore. Pull the bead and trim off the excess. Clean the threads, add a servicable grade Loc-tite and reinstall. OR, If you were carefull you could clean the threads, add the Loc-tite, install the bead and then use a Dremel tool with a small cut off wheel to remove the excess and make it flush with the bore. Either way is acceptable.

thanks kindly.

The thread is a 3x56 as was stated by westpac!van