The standard calibers have a barrel shank diameter of 1.055" X 20 TPI, the WSM and Ultramag shanks are 1.120" X 20 TPI
Here is some more info.
Savage Centerfire Action Lengths
Savage Centerfire Action Length Identification. To help determine what action you have, here are the action screw center-to-center measurements.
Long Action: 5.062" (all years)
3rd Gen Short: 4.400" (2006 - present)
2nd Gen. Short: 4.275" (1998 - 2005)
1st Gen. Short: 4.522" (1959 - 1988)
Striker:
Additional Notes:
- The 1st Generation Short-Actions are today commonly referred to as "J-Series". This is incorrect as a "Series" designation simply refers to a slight design change. Rifles marked "Series J" can be either a 1st Gen. short-action or a long-action.
- The 2nd. Generation Short-Actions comprise most of what you will run across.
- The 3rd Generation Short-Actions are the newest production models and can be easily identified as they will have the new center-feed magazine system. The only exception is rifles originally built in .223 Remington or .204 Ruger as Savage has yet to release a center-feed magazine for these smaller diameter cartridges.
**The best way to remove any doubt as to which generation of short action you have is to measure the action screw spacing.
more.....
Firing Pins & Bolt Faces
Over the last several years Savage has incorporated some design changes that need to be addressed in order to acquire the correct parts for your Savage rifle project.
For the last several years, Savage has used a smaller diameter firing pin on their magnum caliber rifles. The reason behind this is the bolt head retaining pin can use a small diameter through hole which makes it stronger. The standard caliber firing pin measures .145" in the area it would pass through the cross pin, the magnum pins are .095" in that area. Because the firing pin diameter is smaller, the cross pin hole is smaller. So is the the diameter of the hole through the bolt head.
Starting in 2001, Savage firing pin diameters were reduced on ALL models. Therefore, when ordering bolt heads it is important to know what diameter firing pin you have to work around.
On the WSM and UltraMag calibers, Savage changed to a controlled round feed bolt head in order to provide reliable feeding from the magazine. This bolt head differs from the rest by having the bottom lip cut away from the bolt face so that the cartridge rim can slide into the extractor instead of snapping over the extractor. Instead of a spring loaded ejector in the bolt face, this bolt head uses a standing ejector located at the rear of the receiver that pops up through a slot on the bottom left side of the bolt head to tip the case out. This is the only way to get the larger cases to feed from a magazine.
Hope this was helpful. The information came from the Sharp Shooters Supply website.
We use these folks from time to time at the shop, they are first rate folk albeit, they are hard to get a hold of because they are a small operation and constantly covered up with work!
