No, I lost less than 5% of the total range of the fired BBs. I did have to make sure though that I did not leave any metal spurs or bits inside the inner cannon tube once I completed my drilling. I simply took a small steel bristle brush and cleaned the inside of the barrel. It also helped greatly that the outer aluminum tube that holds the flexible hose from the smoker was shaped exactly with a dremel to match to the outside of the inner cannon tube (and directly over the hole for the smoke to pour through).
I also completed a custom barrel mod with a slightly more powerful spring that I purchased from McMaster's Carr. With my new spring inserted and a few adjustments, my BBs now travel about 130% of what they did when the tank was stock. As to the modded arm, I simply made a custom aluminum piece that adds about 10 mm more travel, and then drilled it and the regular pull arm. I then connected the smaller to the larger pull arm with a bushing, and then attached the combo to the outer cannon arm and housing. Because of Newton's First Law, once the recoil begins, the inertia of the outer cannon is enough to cover the extra 10 mm easily. It provides for a slightly exaggerated effect that is cool for kids. I will try to make a video here shortly for you in the coming days.
Also, as mentioned previously, due to my small son, our tank is all about fun first and high detail second. While my son is mildly interested in getting say, the correct phone box on the back of the Abrams, ... that pales in comparison to having a servo operated CROWS station on top of the tank. Anything that moves, shoots, or lights up is tops in his book
One of the best ways to appreciate the beauty of the Universe is learn the language that Mother Nature truly speaks in, ... mathematics.
