Awesome video with excellent explanation. I also love the background music you used in your videos which makes it more soothing, perfectly fits and easier to understand what you are saying and your voice is pretty calm. You deserve more likes and subscribers mate. Excellent job on explaining these technical things 👌 and 👍 keep them coming. Greetings from Bangladesh

Wow, Great quality and extremely helpful video

Awesome video man very helpful and try using some xtac boom gels they are the most consistent size shape and weight and fly the best apparently, azraels armory is using them when testing and doing vids of the customer's builds and Marty rates them really highly ,he said that they are better than the ultras

The BB weight has effect on the barrel to cylinder ratio aswell. The hevier BB you are using, the bigger the cylinder has to be. I would not use anything more heavy than 0.28 in a 1,6 ratio. Otherwise, good video, nice that you mentioned that website with the calculater, it's awesome👍

Hey man what cylinder would I need for 290mm long 7.3 staino barrel?

I new to this, but shouldn’t you be measuring piston travel instead of cylinder length? The remaining cylinder space should then be calculated and added to the barrel volume.

New to the hobby and this explained the principle of volumetric efficiency really well! I bought a 28cm 7.3mm id stainless steel barrel and an 80% ported cylinder for my build. Is this the "correct" ratio?

as long as you're within 5% either way, the efficiency will be fine. Allowing 5% below the cylinder might even be better to account for some takeup in the t-piece. I've just installed a 500mm barrel for my BLG M16. Strictly speaking on my 2.5x7.5 cylinder I want 25cm on my 0.75cm barrel (give or take), but I went ahead and installed a 50cm barrel anyway because that's the faux barrel length I had to play with in that shell. No serious friction loss with lubricated gels on a 1.3 spring. It's accurate out to 2 POA (persons of angle) at 20m, which what I want from a skirmish rifle. I'm sure with a shorter barrel length I'd be able to engage further, but this is a static full-length M16 shell and I need to build around the shell in this case. My other option is a custom gearbox with a much larger cylinder and converting the blaster into a proper DMR, but that will require receiver shell modifications I'm not interested in trying. Myst standard cylinders suit carbine-length builds. If you want a full rifle length build, you'll probably need a larger cylinder and a thicker receiver shell.

The bb weight and the joules you are planning to run does it effect the ratio you want? I have noticed in higher joule builds overvolume is actually better than ideal ratuo. What is your experience about it?

I have done more research,this info is wrong, you have to measure piston travel for the right Ration, so you measure the cylinder from were the O ring starts then to the piston head were it stops.

Ho..im using 80% cylinder...and using inner barrel dia 7mm..450mm ...how long should i cut my inner barrel