.25 vs .20 chrono in aeg with excess cylinder volume

[thekonassure]

Re: .25 vs .20 chrono in aeg with excess cylinder volume

Well my test shows that it can effect some aeg`s too

This is my point that I am getting atleast 10% more muzzle energy with an aeg by using a .25

That`s the point that I`m making is that some people know a gas gun will get more power with .25 but no one seams to even think that some AEG`s might

Well it seams that atleast some do.

[MUCKYMICK]

Re: .25 vs .20 chrono in aeg with excess cylinder volume

of cause your getting 10% more energy at the muzzle using a .25 its heavier their for will have more impact force.
get one full house brick and one half house brick and drop them on your feet from the same hight then tell me which one is more painfull it will obviously be the full house brick as it's heavier so will transmit more energy into your foot.

[ElCarl]

Re: .25 vs .20 chrono in aeg with excess cylinder volume

Of course you're getting 10% more energy at the muzzle using a .25 - it's heavier, therefore will have more impact force.
Get one full house brick and one half house brick and drop them on your feet from the same height then tell me which one is more painful. It will obviously be the full house brick as it's heavier, so will transmit more energy into your foot.

Please don't spread misinformation - gravity is different, as it accelerates ANYTHING at the same rate (ignoring air resistance) - ~9.8ms^-2.
An airsoft gun works on an entirely different principle...

[Portnoy]

Re: .25 vs .20 chrono in aeg with excess cylinder volume

Inertia people, inertia.

[ElCarl]

Re: .25 vs .20 chrono in aeg with excess cylinder volume

[Physics]

Imagine throwing a cricket ball (or baseball) compared with throwing a tennis ball. You can probably transfer a lot more energy to the cricket ball, as it would hurt a lot more when it hit.
That's because you can only really accelerate it so quickly when you throw it; you haven't expended all the force you could when the tennis ball's already out of your hand, however, the cricket ball would still be accelerating, further back in your arm motion.
And due to ke=1/2*mv^2, the more massive object moving at the same speed will have more energy. THAT'S why it has more muzzle energy... Not only because it's heavier.
If you applied exactly the same amount of force to two objects of different mass, over exactly the same timeframe, they will have the same amount of kinetic energy.


For example: 0.2N applied to a .2g and a .3g projectile.

a=f/m
where a=acceleration in ms^-2, f=force in Newtons, m=mass in kilograms.

For .2g:
a=0.2/0.0002
a=1000ms^-2

For .3g:
a=0.2/0.0003
a=666.7ms^-2


Ok. Now assume this is accelerated over 0.1 seconds:

.2g: 0.1*1000 = 100ms^-1
.3g: 0.1*666.7 = 66.7ms^-1


Now the energy of those two is:

.2g: 0.5*0.0002*100^2
= 1 Joule

.3g: 0.5*0.0003*66.7^2
= 0.667 Joules


After being accelerated over the same timeframe, the heavier projectile has gained less energy. However, they have not covered the same distance - and a barrel in an airsoft gun has a fixed length. We'll see how much energy each projectile has if they cover the same distance while being accelerated.

We'll use the distance the .2g BB covered as the barrel length, as 1 Joule is a nice, round target.

s=ut+0.5*at^2

s=(0*0.1)+(0.5*1000*0.01)
s= 5 meters

Not very realistic, but oh well. It will do as a demonstration.
So, we have a distance to work out how fast the .3g BB will be travelling after it has travelled 5 meters.
Luckily, the initial velocity is always 0 in these, which makes them a lot easier.

v^2=u^2+2as
v^2=0+2*1000*5
v^2=10000
v=100ms^-1


So energy:

.2g: 1 Joule
.3g: 1.5 Joules

I think that's what I set out to prove... Hmm. Anyway.

I may have made a stupid mistake - assumed something wrong, simple calculation error, whatever; if so, please point it out to me...


[/Physics]

[The General]

Re: .25 vs .20 chrono in aeg with excess cylinder volume

Sites insist on chronoing a gun with .20 weight bb's because its not a nightmare then trying to calculate energy levels with different weight bb's and many chrono devices cannot do this themselves. There simply is not time to sit there for 5 mins with each customer working out all the variables.

When I am chronoing 150-200 people I want to know the gun is doing under 351 (AEG) with .20's. That's what my site manager is asking me to do.

People who then use a heavier bb with the gun that passed this test do get a slight energy advantage, I think we all understand this don't we?

Its all about practicality and a set standard that everyone can live with.

Its the sites decision what and how they set limits and how they are measured. There is no legal requirement AT PRESENT.