Pete: yup, 30 inch long Palma barrels typically use a 1:13 twist. My first Palma barrel had a 1:12.7 twist, two of the other three had 1:13 twists and one had a 1:12 twist.
I think a couple of Brits from England had 1:14 twists in their Palma barrels when Sierra's 155's were first used in a match back in 1991. They shot those bullets very well at 6600 feet elevation where the air's thin and they could get away with a slower twist.
US Navy Distinguished Marksman Badge 153
Former US Navy & Palma Rifle Team Member
NRA High Power Master & Long Range High Master
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