Lately there have been a few threads asking about identifying the new or old MKII and 93 actions. Savage used to make two different receivers/actions. One for the MKII (.22lr or .17hm2) and one for the 93 series guns (.22mag or .17hmr). Sometime in the past year or so Savage started making the "E-Receiver". The e-receiver is now used for all of the 4 common rimfire calibers. Here are some pictures that show the past and present guns.
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2003 - Savage introduced their new ACCU-TRIGGER. Besides the trigger change, the receiver now has a round top in the rear scope base area which uses the same base in the rear as in the front. The Weaver #46 base will fit both ends as well as the #402 extension base if you have a need for mounting extremely long or short tube scopes.
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The following measurements depict the various screw spacing on Savage 110 centerfire actions over the years. All measurements are center-to-center.
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In 2002 Savage began offering rifles in the Winchester Short Magnum (WSM) and Remington Ultra Magnum (RUM) calibers. When these were finally in the catalog, there was a change made to the barrel shank diameter. Standard barrel shank diameter on standard calibers are 1.055" x 20tpi. On the new WSM, RUM, and SAUM calibers the shank diameter is 1.120" x 20tpi.
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