Micro-Ports

[alordnapa]

I have been contemplating the physics of drilling very small ports ( Tiny wire drill sizes) in a .22 LR/Short rifle barrel. For the sake of discussion, lets say its a bolt or other closed action firearm with no breech gas leakage. The idea being to bleed off gas after the projectile reaches a minimum velocity, and that the bled off gas would convert gas as energy into ultrasonic sound and tiny little wisps of residual gas. ( Yes, I know the holes will plug up and burn, and hot gasses would be spraying wildly into the air) Here are my primary questions: 1) Would this be a "Silencer" under Federal and State Laws? 2) Should the holes be of smaller diameter closer to the breech, and larger closer to the muzzle? Should the gas be vented geometrically? logarithmically? etc. By virtue of the spacing between holes?

[Capt. Link.]

I have been contemplating the physics of drilling very small ports ( Tiny wire drill sizes) in a .22 LR/Short rifle barrel. For the sake of discussion, lets say its a bolt or other closed action firearm with no breech gas leakage. The idea being to bleed off gas after the projectile reaches a minimum velocity, and that the bled off gas would convert gas as energy into ultrasonic sound and tiny little wisps of residual gas. ( Yes, I know the holes will plug up and burn, and hot gasses would be spraying wildly into the air) Here are my primary questions: 1) Would this be a "Silencer" under Federal and State Laws? 2) Should the holes be of smaller diameter closer to the breech, and larger closer to the muzzle? Should the gas be vented geometrically? logarithmically? etc. By virtue of the spacing between holes?

If you are trying to reach a degree of suppression then a stamp should be applied for.
Two small ports in the chamber throat will drop velocity below supersonic for a .22. The heat and pressure will keep the ports clear and the small size will not affect accuracy. Ports further away from the chamber will need to be larger and more numerous and may affect accuracy. Symmetry with little lead shaving is desired. Look up H&K MP5SD porting development.
You are aware that patents exist that use ultrasonic whistles, I know of three plus one that uses duck calls!