Correct size drill bit for a replacment front sight

[Harv 24]

I've seen different sizes on the various forums/videos calling out anywhere from a #54 a #55 or a #56 drill bit to drill out the front sight on a S&W.

I purchased a new Dawson Fiber optic front sight for my 617 and will be replacing it when it comes back for Smith.

Which is the correct bit to use?

 

[The Norseman]

Dawson Front Sight

Very good question. I know this has been
addressed before and one of the Enthusiasts
will be along to tell us.

Say what barrel length S&W Mdl 617 are
you putting the Dawson front sight on.

Also what is the Sight manufacturer’s number?

Thanks again.

 

[Harv 24]

Sight, for Smith & Wesson® Pinned Revolvers, Fiber Optic Front, by Dawson Precision®

050-694

Brand: #1 Dawson Precision®

Sight Height & Width: .170" Tall x .100" Wide Ramped Serrated

It's for the 4" barrel.

I like my zero-center bullseye hold and my rear sight is bottomed out. the blade that came with it measured .154" if I recall.

Which to me seems too low for an adjustable rear tgt sight.

 

[stang1911]

#54 drill bit which is .055