Latest Version(s)

Mk3.5 (type A: multi gun/barrel version)

https://www.simpleplanes.com/a/b7dEV8/Cannon-damage-tester-Mk3-5-for-kinetic-damage-only-impact-damage-scaler-muzz

Type B Mk1 (single gun version)

https://www.simpleplanes.com/a/62Uzfy/Cannon-damage-tester-B-Mk1-block-mass-900000

Contraption to test average kinetic damage of cannons (not explosion damage, not with this version!) per the impactDamageScaler and muzzle velocity (and maybe diameter, too). I recommend you don't change cannon's diameter/caliber, though, they don't have as much effect on kinetic energy as the other two mentioned above. It has more effect on explosion damage/area (along with explosionScale value).

Unlike the previous version, this one has 8 cannons to let you get larger sample size per test, and each cannon will automatically stop firing once the block is destroyed.

Plus, it has a nice rudimentary counter & calculator that shows you the number of rounds fired, average number of rounds fired, and average damage dealt*.

*"Average damage calculator" of this version doesn't take into account the "overkill" amount of damage. I'll try to remedy this with later version.
In the meantime, you can increase accuracy by increasing the block HP. Make sure to change HP of all blocks (that get hit by cannons) by the same amount.

I hope the calculation is good, but if you find any severe error in FT, please let me know right away.

Also, values in variable setter are just for the label & calculation. They don't change the actual velocity, HP, etc.