You need to do a chamber cast, or get a gunsmith to do it for you. Should be pretty cheap, or there's instructions on youtube on how to do it yourself. Basically you create a mold of the chamber after plugging up the bore and then measure the dimensions and compare to cartridges.
“
The Savage 99 Pocket Reference”.
All models and variations of 1895’s, 1899’s and 99’s covered.
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