[M.J]

Perfectly done, good work!

 

[M.J]

I would add that a larger cross-section makes for a heavier draw but not necessarily a faster band. Fatter tubes are better for large ammo but more layers of thinner tube will be faster. For example I would almost guarentee that 4-strand (one loop per side) 1842 is faster than 2-strand (one tube per side) 3060 even though the total amount of rubber is comperable.
It's all about matching bands to ammo.
8-strand 2040 (two loops per side) is the bomb, though

 

[M.J]

Very useful chart! Using the supplied cross sections backs up my trial and error findings.
My three favorite tube setups are: single 3060s, doubled 2040s, and single Theraband Yellow. These fall in a range of 3.5mm (15% or so) with 2040s on the low end and TBY on the high.
Thanks Hrawk!

 

[M.J]

I just thought I'd add the measurements for the Simple-shot dipped latex medium and large tubes.
Medium cross section area is 16.13mm, making it just a trifle smaller than 2050
Large cross section is 23.75mm, or just slightly smaller than 4070.