Airsoft Canada - View Single Post - Is this a good way to swap from CQB to Field?

lurkingknight · February 14th, 2013, 10:24

yes, you'll have to leave it in the gearbox if you want the hotswap barrel option. It's not an ideal setup since you are intentionally mismatching your cylinder air volume to your barrel volume. What happens is with heavier rounds, they will have slightly more time to accelerate since they take longer to get moving...

The anomaly you'll see is that while you may still chrono at 350 with .2s which is 1.13 Joule of energy,but with say a .3 you may actually see higher fps (and therefore muzzle energy) when still expecting to see 285fps at 1.13J. It's an example of what can happen, it will depend on a bunch of variables, air seal, piston weight, spring... it's sort of hard to calculate until you throw it together an actually chrono with different weights of ammo.

What's important is if your indoor limit is 1.13J, you should be chronoing at that or lower with the ammo you are going to use indoors. And why J is important is because that's the statistic that matters for impact rating. It's just that FPS with a known, uniform weight is easier to measure since not all chronos can calculate J.

February 14th, 2013, 10:24	#5
lurkingknight "bb bukakke" KING! Trader rating Join Date: Jul 2011 Location: Ottawa	yes, you'll have to leave it in the gearbox if you want the hotswap barrel option. It's not an ideal setup since you are intentionally mismatching your cylinder air volume to your barrel volume. What happens is with heavier rounds, they will have slightly more time to accelerate since they take longer to get moving... The anomaly you'll see is that while you may still chrono at 350 with .2s which is 1.13 Joule of energy,but with say a .3 you may actually see higher fps (and therefore muzzle energy) when still expecting to see 285fps at 1.13J. It's an example of what can happen, it will depend on a bunch of variables, air seal, piston weight, spring... it's sort of hard to calculate until you throw it together an actually chrono with different weights of ammo. What's important is if your indoor limit is 1.13J, you should be chronoing at that or lower with the ammo you are going to use indoors. And why J is important is because that's the statistic that matters for impact rating. It's just that FPS with a known, uniform weight is easier to measure since not all chronos can calculate J. __________________ I futz with V2s, V3s and V6s. I could be wrong... but probably, most likely not, as far as I know.