BB question, Weight at constant Joules
 

It used to be the case that a field would have an FPS limit set with .2 gram bbs and allow the use of heavier bbs with the assumption that as the weight increased the FPS would go down and total energy would remain about the same. OF course we know that for most Guns heavier BBs result in a net gain in joules of energy (FPS does not drop off as fast a BB weight increases) so heavy bb's would fly farther and hit harder than light ones even with the same spring/compression setup.

Our field now has a joule limit, which means FPS is set per BB weight actually used not at .2 (unless you are using .2s in the game itself.)

So my question is this does it still almost always make sense to use the heaviest BB you can get for out door use if the joule limit is identical across BB weights?

My field limit is 1.64 joules which is 420fps at .2, 377 at .25 and 344 at .3, 298 at .4 etc...

Wouldn't there be a sweet spot below .43 or is it still best to get the heaviest BB you can afford?

Apologies in advance if this question is deemed absurd.

You could technically run .43s if you want but you have to take into account just how slow your muzzle speed is with that weight of ammo.

Stealth other than time to impact would my range/accuracy still improve? .43 for instance is 287fps at 1.64 joules.

As long as you remain under the joule limit, you can use whatever ammo you feel gives your desired results.

Or which ever your wallet can support.

Knowing nothing about your exact setup, I don't think it would be even a ballpark guess to know if you will benefit from using .43s vs .36s or .32s or whatever.

Shoot some and decide.

Sure - if your gun can even lift that weight of ammo, if your cylinder can support that volume, if your .43s are of good quality, etc.

There's a lot of things in play.

For a 420fps gun, the widely accepted sweet spot hovers between .28 and .32

You wouldn't have enough hop applied unless you were using an ER-hop, and even then the BB is traveling so slow it's simply a matter of how far it's going to go before gravity pulls it down.

The optimal round on a conventional hop rubber I've found is the .30s and .32s at 1.64j
Good balance between velocity, accuracy, and range

Whatever energy you gain from joule creep, you lose from the hop up necessary to lift those rounds.