A couple years back the PGA Championship held a long drive contest , Louis Oosthuizen won with a drive of 340 yards. 50 years prior , in 1963 they held the same LD competition .
BTW! Jack Won that with a drive of 341 yards using a small headed persimmon driver, steel shaft and wound ball.
Jack was consierably longer than his peers. They didnt officially measure distances or even capture stats back then. However, One year in the mid -late 60's IBM did an analysis of all the drives on certain holes from something like 15 PGA events. I dont recall the exact numbers but Jack was something like 5-7% longer than the tour average and had an average drive length measured of something around 275 yards.