I use the listed 8.3gr max load of Ramshot Silhouette with 124gr FP Xtreme plated. In the 4-1/4" barrel it seemed to be fine, but in the 5" I'm seeing maybe 10% keyholing, so I'm going to back off a bit on the next batch -- the velocity must be borderline in the longer barrel. There are no pressure signs or case expansion with the soft plated lead at the max load, and plates go down really well.
I just looked up my chrono results: with the starting 7.9gr load the velocity was 1227 average in 4-1/4" and 1170 in 3-1/2" (I didn't have the 5" barrel then). The max 8.3gr should add about 60fps, so the combined effect should put the 5" max load at about 1343fps, which is indeed borderline for plated. Since I don't shoot the 3-1/2" barrel any more, I think I'll drop back to 7.9gr. on the batch I'm prepping now.
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