I have a Ruger Number 3 in .45/70 and want to scope it. I'd want to use Ruger parts if possible. Is it necessary to drill and tap and where can I get the parts?

Welcome to the forum veger2. Rules are simple, be nice and join in.

Your barrel should be tapped for Ruger's and other's bases.

Ruger #3's did not come with a scope base like the #1's do. Ruger made/makes a two piece base set, which takes Ruger ring. #3's also take an aftermarket two piece base setup, Weaver, Redfield, other.

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Bob from Idaho

It depends. Early #3 Rugers were not drilled & tapped for scope bases. If your rifle has 4 small slotted plug screws on top of the barrel between the rear sight and the front of the receiver it is already drilled. If not then you would need to have this work done.

Bases are available from Ruger, Brownell's, etc. You may also be able to use the Ruger #1 half rib from the #1 .45-70, Ruger customer service may be able to tell you if it will fit.

If you need to have it drilled, by all means pay a gunsmith to do it for you. This is a basically simple operation, but not what you want to approach as a first project, unless you are a qualified machinist.