Very nice gift. That's a beauty - love the Octagon BBl.
I can't handle full on 475s any more. The last time was in 2015 - wow didn't realize it was that long ago. A very nice load is 8.5 to 9.0gr of Win 231/Hp38. Here's a group I shot with 400gr Lees but it should work fine with any bullet weight. Here's a source of reasonably priced 370gr coated 475s
https://tbbullets.com/bullets/polymer-coated-handgun/480-ruger/8.5gr HP38 load
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Paul