I haven't bought any Thera Tube rubber for a long time, as I mostly use the flat type. But the new launchers I recently made work well with tubing, and my stash was dwindling away quickly.
So I ordered some new silver, black and blue tubing. I put the silver on my Blunderbuss, and was immediately stunned by the stretchiness - and the speed of the shot.
I compared the old and new types, and the difference was totally obvious. The new tubing is much thinner. See the new and the old silver in comparison:
I measured the draw resistance, and it was identical (about 17 kg at full stretch). This means that the new tubing is 39% more efficient!
I then looked at the black type. The same thing! See the old and the new:
Same thing - the old type weighs 0,57 gramms per cm (actually more than the old silver), whereas the new black type is 0,43 gramms per cm only. 25% less! Same draw resistance (7,5 kg at full stretch). #
I tested the weight of the flat type (Thera Band Black) and 0,49 gramms per cm. This means that the new tube is 12% lighter than the flat bands - which used to be 13% heavier! The weight ratio has been completely reversed.
I will do some chrony tests today. But my experiences so far have been very promising. Maybe we will see a comeback of tubular bands for performance oriented shooters.
Here is one more pic, the new silver compared to the old black: