Not entirely sure about the marks being lathe chuck marks- if they are, it's a 2-jaw
Those look almost like roll-over crimp die marks- seen very similar on high tensile hydraulic hose end fittings. She coulda skidded a bit too, during boring. I probably have the deep-end cut off here.
I'll keep an eye out for the 10.3 JSB's. Somewhere in my travels, I've seen Cr FT domes in boxes marked .177. Must be Cabela's.
Still can't get over the groups I'm getting with the yellow tin meisters, and yes, they're going fast. Not a huge problem here as Wholesale Sports still have a sleeve or 6 in stock...
Gun doesn't like the 2900 psi it's supposed to be factory tuned for- I'm getting partial valve lock burps and hiccups that high. 2400-2500 seems to be the sweet spot for this pistol...
Regards,
Doc Sharptail