Help! Measuring for BSL..., How To

[BrianE]

I have a (new to me) pair of used 1st gen Scarpa F1 boots w/bellows. Inscribed on the instep of each shell is the BSL however rather than being expressed in mm's it's expressed in what I believe to be US shoe size 6.5 - 7. FWIW, the liner is a 26mp. I hoped to mount up a pair of Meidjo's (using their paper jig/template for use with these boots but I am feeling somewhat stuck as I am not sure how to convert/translate a US 6.5 - 7 BSL into mm's. Is BSL simply measured following the curvature of the boot sole tip to tail or just straight line tip to tail? Or, is there a known good formula for doing the conversion from US shoe size to BSL where it's expressed in mm's....???

[Woodserson]

I only have 75 experience, but my Scarpa T2 stamped sole length is measured from the front of the duckbill to the back of the heel, and it's dead nuts accurate to what is stamped on the shell.

[BrianE]

...but my Scarpa T2 stamped sole length is measured from the front of the duckbill to the back of the heel, and it's dead nuts accurate to what is stamped on the shell.

Wooderson - Thanks for the quick reply. Just to be clear, the method of measuring which yielded the same length as what is stamped on the shell is via following the curvature of the sole (front of duckbill to the back of the heel) or straight line (front of duckbill to back of the heel)? Sorry for being so OCD, I just want to be certain I understand....

[Montana St Alum]

I have a (new to me) pair of used 1st gen Scarpa F1 boots w/bellows. Inscribed on the instep of each shell is the BSL however rather than being expressed in mm's it's expressed in what I believe to be US shoe size 6.5 - 7. FWIW, the liner is a 26mp. I hoped to mount up a pair of Meidjo's (using their paper jig/template for use with these boots but I am feeling somewhat stuck as I am not sure how to convert/translate a US 6.5 - 7 BSL into mm's. Is BSL simply measured following the curvature of the boot sole tip to tail or just straight line tip to tail? Or, is there a known good formula for doing the conversion from US shoe size to BSL where it's expressed in mm's....???

I'm not even sure I understand the question, but I'll just throw data out on the off chance it helps. I have 26.5 Tx Pros. They have 26.5 liners (about 9 to 9.5 U.S. - I don't know what 26 mp is) and are stamped as 307mm. That's the entire length (is that the BSL?). The length from the center of the tech fitting up front to the back is about 292mm. The curvature is so small as to be insignificant in those measurements, Vs. point to point.