Gas checks being as expensive as they are, and wanting just a plinker at about 1200 FPS in my .30WCF sagebrush hike carbine, I milled just enough off the top of my Lee, .309 150 grain Flat Point mold (number 90366) to make a flat base boolit with no gas check shank. I then remounted the sprue plate. The resulting boolits are approx. 135 grains from wheel weights, and are the perfect plinker. They are more accurate than the .309, 113 grain Lee Flat Point, mold number 90362. Plus, as an inconsequential bonus, the shells with the 135 grain slug look "right" (proportional), which is always so important to Jack Rabbits.
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Edit: Hopefully this is a picture of the original bullet and the shorter, 135 grain new one.