I've loaded extensively for the .25-35 in my 10" Contender, I even used it to shoot my first 40x40 in IHMSA silhouette years ago. Some of my most accurate loads:
87 Speer SP....23.0/RL-7..........2303 fps
87 Speer SP....25.0/H322.........2024 fps
87 Speer SP....26.0/IMR3031....2044 fps
117 Horn RN...24.0/IMR3031....1975 fps
While these are below manual maximums, work up from a few grains below.
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