How does the BATFe determine if a thing on the end of a barrel is a flash suppressor or a muzzle break/ compensator?    Don't compensators like the Vais do some part in decreasing flash?   Does a flash suppressor decrease recoil and muzzle rise?   Just trying to understand the definitions a little more.
thanks

anyone? anyone? anyone?

Thanks!

They have equipment to measure muzzle flash.

The A2 flash suppressor/compensator does both, it dissipate flash, while its bottom is closed, it vents gas upward to help keep the muzzle down.  A device such as Phantom, Vortex, A1 birdcage suppressor only suppresses flash it does not decrease recoil or help with muzzle rise.  A flash hider simply hides it from the shooter to preserve his night vision but not necessarily diminishes it, remember the cone-shaped hiders on WWII weapons...
A brake helps in reducing the felt recoil.  We can still see these in use on artilery.
[img]fas.org/man/dod-101/sys/land/m2_1.jpg[/img]

From what I hear, many MiniY brake users feel like the above pic when they fire their weapons.
[:d][:d][:d]
I'm incomplete on any of these, please feel free to correct me.

No, the Mini-Y users don't feel that way, it's the guys on either side of them who feel that way.   [cuss]

[rofl] I've been on the receiving end of many a Barret .50 rifle blast and concussion, to me it was kind of fun.