I used to pull the fmj bullets and replace the powder with 8 or 10 gr of W231 from memory , a little cotton wool on top of the powder and sit the fmj back on top. They worked fine on deer with chest shots as the fmj bullets tumbled on impact and always seemed to exit the rib cage side on.
Try the .311 185gr lee cast bullets. they shot fine for me but I usually just used the fmj.
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