Barley is classified into varieties that have good malting properties and those that are best for feed.
https://ambainc.org/https://ambainc.org/amba-publications/know-your-malting-barley-varieties/Of the varieties that are best for malting there should be little difference in the brewhouse between those that are spring and those that are winter.
Spring barley being planted in the spring and harvested late-summer/early fall. Winter barley being planted in the fall and harvested mid-late summer.
The majority of malting varieties are two row spring planted barleys.
The size of the kernels you have points to a two row barley, with good terrior which was well cared for by the farmer. IOW, the barley had a good growing year and the farmer planted, cared for and harvested it appropriately.
Adjusting your mill for the particular barley (or grain) you're milling would be appropriate. Most just become accustom to leaving their mill set at one setting for convenience and then post on a forum about stuck mashes, poor efficiencies or how their grain isn't ground right etc...