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Hi all,
Recently I received 2m of Precise Green. Since I almost exclusively use TBG I wanted to compare them.
I cut 2 bands of TBG 2cm wide each and 15 cm active band length, and 2 bands of Precise Green also 2 cm each and 15 cm active length.
I used stretch factor of 5, the one I use always, although I know that this is recommended ratio for TBG; for Green I can only hope so.
I stretched them both to 75 cm (5x15) which gave me elongation of 60 cm each (75-15).
I measured the power at 75 cm for each pair of bands 10 times with pre-stretch of 10 times each.
First I noticed that TBG looses power rapidly after each stretch, starting with 5100 grams (1st measurement) and ending with 4480, (2nd measurement). Green had more consistent values.
I took last 5 TBG measurements since they were more consistent and got average power of 4580 g. I did then the same with Green and got 6680 g as an average. (I am inclined to doubt my own results since Green is even thinner than TBG (0.45 Green vs 0,635 TBG). For bands of same widths I would expect apposite..)
The weight of 2 TBG bands was 3.69 grams and Green had 3.47 grams.
Then I mathematically narrowed the Green bands from 4 cm total to 2.74 in order to have same power as TBG. However, the Green bands weight is now even smaller, 2,38 grams.
In total, the math that I am developing lately tells me that a slingshot banded with this set of TBG would propel ammo of 3.55 grams (9.5 mm steel ball and with a pouch of, say, 0.53 grams) to 67.45 m/s.
The Green bads of the same draw power (those that are more narrow now, being 2.74 cm in total) would propel the same ammo and with same pouch to 71.52 m/s.
However, the velocity of bands only, that is, without pouch and ammo, for TBG would be 120.88 m/s and for the Green 150.51 m/s.
To be honest I have no idea is this whole experiment and math are any valid. I would like to hear your thoughts and experience.
cheers,
jazz
Recently I received 2m of Precise Green. Since I almost exclusively use TBG I wanted to compare them.
I cut 2 bands of TBG 2cm wide each and 15 cm active band length, and 2 bands of Precise Green also 2 cm each and 15 cm active length.
I used stretch factor of 5, the one I use always, although I know that this is recommended ratio for TBG; for Green I can only hope so.
I stretched them both to 75 cm (5x15) which gave me elongation of 60 cm each (75-15).
I measured the power at 75 cm for each pair of bands 10 times with pre-stretch of 10 times each.
First I noticed that TBG looses power rapidly after each stretch, starting with 5100 grams (1st measurement) and ending with 4480, (2nd measurement). Green had more consistent values.
I took last 5 TBG measurements since they were more consistent and got average power of 4580 g. I did then the same with Green and got 6680 g as an average. (I am inclined to doubt my own results since Green is even thinner than TBG (0.45 Green vs 0,635 TBG). For bands of same widths I would expect apposite..)
The weight of 2 TBG bands was 3.69 grams and Green had 3.47 grams.
Then I mathematically narrowed the Green bands from 4 cm total to 2.74 in order to have same power as TBG. However, the Green bands weight is now even smaller, 2,38 grams.
In total, the math that I am developing lately tells me that a slingshot banded with this set of TBG would propel ammo of 3.55 grams (9.5 mm steel ball and with a pouch of, say, 0.53 grams) to 67.45 m/s.
The Green bads of the same draw power (those that are more narrow now, being 2.74 cm in total) would propel the same ammo and with same pouch to 71.52 m/s.
However, the velocity of bands only, that is, without pouch and ammo, for TBG would be 120.88 m/s and for the Green 150.51 m/s.
To be honest I have no idea is this whole experiment and math are any valid. I would like to hear your thoughts and experience.
cheers,
jazz
