Explain clearance verses HS. And did you do a chamber cast to know the length of your 1917?
You ask this question of one of only two reloaders that can measure a chamber for head space/length of a chamber, thank you.

No, for me it was easier to measure the length of the chamber from the shoulder of the chamber to the bolt face. The 280 Remington case is .051" longer than the 30/06 case from the shoulder to the case head. When it comes to forming cases I cannot miss with .051". long story to make you dizzy, when measuring long chamber, I use a forming die with a feeler gage to adjust the die off of the deck of the shell holder. After forming/sizing I measure the length of the case from the datum (.375") to the case head for final adjustment.

After I make final adjustments, I adjust the die to .014"off the deck of the shell holder, the .002" gives me .002" clearance on my newly formed/sized cases.

F. Guffey

The length of my chambers is measured in thousandths.

Component manufactures do not manufacture cases to reloaders that know what they are doing, if they did, they would add a few thousandths to the case between the datum/shoulder to the case head.