FPS to joules on crono

[Earpy69]

So I’m trying to figure out what the joules are when the crono is set on .20 and you use .32. I know that on .2 at 350fps it’s 1.14, so dose this mean the max for .32 at 350fps would be 1.82 or would that be over the uk limit. 
I know there’s charts and website you can look at and manually input, just wondering if there was already a chart that is correctly set upView attachment 120385

 

[Hudson]

It doesn't work like that, you've kind of got it backwards.

The allowed joules will stay the same, and your FPS will lower accordingly. You'll want to be under 276fps if you're using 0.32s.

Here's a slimmed down one that's useful for most UK places.

View attachment 120394

 

[EDcase]

Here you go: Zero One Airsoft FPS & Joules Calculator

 

[Enid_Puceflange]

Or this one, for iOS 

https://apps.apple.com/gb/app/airsoftcalculator/id1473060972

 

[Galvatron]

Alternatively, you can use this formula in Excel or similar spreadsheet programme depending on whether you use feet per second or metres per second so you can see the workings of how kinetic energy is calculated

=1/2*(cell with weight in grams/1000)*(cell with speed in fps/3.28084)^2

=1/2*(cell with weight in grams/1000)*(cell with speed in m/s)^2

 

[Rogerborg]

Can I ask the purpose of this question?

The cheapest airsoft chronos that you can buy at the moment allow you to store multiple BB weights, generally 6, and switch between them with the push of a button.

You set the chrono to the weight that you're using, and you look at the Joules number.  End of story.

I can tell you what energy my guns run at on various BB weights, but have no idea what fps they're shooting at. Why would I need to know?

 

[Cr0-Magnon]

I can tell you what energy my guns run at on various BB weights, but have no idea what fps they're shooting at. Why would I need to know?

I know both...because I always use 0.28's in my rifles and obsess over getting them to 285fps.

 

[Rogerborg]

I know both...because I always use 0.28's in my rifles and obsess over getting them to 285fps.

Do your local sites still look energies up on a chart, or do they set the chrono to the BB weight and look at the Joules figure?