Baffle designs - best design and why

[shorty]

As time goes bye, it's becoming more important for my airguns to be more and more quiet. I really do not want to attract attention from my neighbors.
Lately I have been trying different styles of baffles in the same size can.
M - k- cone- custom weird stuff- and sound dampening material in combination.
To me, the cone baffles appear to be the quietest everytime.
Although, I just can't get it quiet enough for my liking.
Iam planning on trying a stepped cone next but, I would like to know what you all thought was the best type.
Since all testing was done with a 1 inch diameter can 6 inch long, I would also like to know if diameter vs length is linear to sound or not.
Yes I know what cal and efficiency. So I am working on .177 cal at 25fpe and efficiency of around 1.2.
I can drop the power to 10 or 12 fpe and it's to my liking but that's not where I want it.

So what do you think is optimal for can size and baffle design?

[Insanity]

Try adding a expansion chamber that is just empty test it before and after your baffle stack. I have seen it work on a .50cal and the added 1/3 length of just empty tubing made a very notable difference in the decibels emitted.

[JPSAXNC]

Hi Tim, I like cone type baffles. But the biggest factor that I have found is the hole size. A couple thousandths bigger than the pellet is quiet, 5-6 thousandths bigger is way to loud. HTH.