I need to know if Leupold QR bases are weldable? I don't know if they are milled steel, cast, sintered or what not.

I have a preWar Win 70 in 416 Rem (formerly 300 H&H/Wby) that is drilled and tapped for a Redfield JR-70 Mag base.

Leupold doesn't make QR's for preWars specifically, although it is no big chore to use later 70 bases. The worst part is they don't make a one piece QR base for long action Win 70's at all. I would prefer to use a one piece base as I am putting a Lyman 48 WJS aperture sight on this rig. I have used Lyman 48's in conjunction with 2-piece QR bases by milling the top of the base and mounting screws down until the aperture will clear the scope tube.

I want to weld the QR 2-piece M70 bases into a one piece base as that Lyman 48 fits very nice behind the Redfield JR base. I don't trust the Redfield JR base on a 416 Rem in the first place and they really aren't my first choice by a long shot as being a QR setup.

IIRC Leupold rings and bases are made from 12L14.

I buy steel from the same vendor as Leupold.
The vendor has a lot of inventory of 12L14 and 11L17 in certain sizes for Leupold's use only.

James Wisner
Custom Metalsmith

Leadloy or 12L14 is weldable. it's not the greatest but it will weld. use a mild steel rod 70S is fine. What ever you use for a patch between the bases I'd try to get a chunk of 12L14 as a mild steel bar may pull the weld away from the base when cooling and crack the weld. Don't ask How I know