Yeah, Savage started transitioning to the 1-10 twist about that time. Have owned a couple of the later 99 .250s with the 10 twist--but some other companies stuck with the 1-14. Winchester made a lightweight Model 70 in the 1980s that was chambered in the .250 with the slow twist. It shot 100-grain Speers very well, and probably 100 Interlocks as well, but I'd have to look at my loading notes to see. This doe was facing me at around 150 yards, and a 100-grain Hor-Cor at the base of the neck dropped her right there.

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