Which BB wight is best?

What should i use for a AEG shooting 300-400 FPS?
What should i use for a Bolt-Action sniper rifle shooting 500-550 FPS?
What should i use for a pistol shooting 275-325 FPS?

This is just a minor topic i am putting out here for anyone that requires help such as myself on BB wight for different types of guns.

In my opinion a standard AEG shooting 300-350FPS should use .23g BBs
350-400FPS should use .25g
Pistols should use .20-.25g BBs depending on it's range.

I haven't touched a bolt-action sniper rifle in a while but probably something between .3g and .4g.

I'd also take note to the brands. Some brands do fly better than others. Here's a pretty interesting research project done a few years ago. I believe all research was done with .20g BBs though, but it'll give you an idea. http://www.airsoftmechanics.com/home/content/view/19/26/1/0/
I wish things like this would be done more often with a wider range of ammo.

Really dont think there is a best BB weight for whatever FPS its just a matter of personal preference and what your gun likes to shoot. My gun shoots .20s like a champ but they really suck if its at all windy. .25s is what i shoot 95% of the time and they shoot awesome but if its really windy i may go too .28s. You will have to try some different weights and brands and see what works best for you.

Im with Tom on this one.

Where I may not shoot with AEGs too often, I do however use heavyweight BBs for my sniper platform. These weights vary to keep the shots accurate. And of course depends on the conditions. However I try to keep the weight consistent since I hate adjusting my hop up over and over again.

Once you start shooting over 500 fps you will want to use heavier weight BBs to keep the accuracy and gain some range...sacrificing fps for a straight shot is fine with me. Different brands shoot differently. When I was shooting under 500 MAdbulls were working great, but now I use Goldenball or the SGM .29s (Best on the market)

But of course now I have to readjust everything once I find a suitable Bio BB to put through.

i like .76