Technical information

Practical A.E.G Upgrade 2006

0.20g BBs versus 0.25g BBs versus 0.30g BBs: the heavier the better?

Does FPS always go hand in hand with Joule?

What is the difference between the FPS system and the Joule system?

How do you use FPS to measure Joule?

How do you use FPS to give an estimate of the range?

If you plan to upgrade to 400FPS+, you may better also move to 0.25g BBs.

0.20g BBs are way too light at this power level and will not deliver the accuracy

you need. If you plan to go over 450FPS+, consider the use of 0.30g BBs for

maximum flight path stability. Marushin has some very nice 0.30g BBs (USD$18

something per bag of 1800…  ).

By the way, heavy BBs do drag down FPS quite a bit (due to the heavier weight)

but may produce higher impact (also due to the heavier weight). They are VERY

expensive though… you should really take this cost element into consideration

when defining your desired upgrade level.

As previously stated, heavier BBs may produce higher impact. What this

indicates is that FPS rating alone may not truly reflect how powerful an AEG is.

While FPS measurement (feet per second) looks primarily at the “speed” of the

flying bullet (i.e. the muzzle velocity)(!), Joule measurement (a system

commonly in use in the UK) does take bullet weight into the equation to more

accurately measure the force generated (i.e. the impact energy). In fact, we at

The AirsoftPRESS prefer Joule measurement over FPS. However, it seems like

the market in North America is biased totally towards the FPS system.

(!) For FPS measurement to deliver fairer results, one should REQUIRE all

participating guns to use BBs of the same class (eg. 0.2g) and have hopup

completely released.