Functional crown dynamics

[delooper]

Has anyone here tried a functional test of their barrel crown?

I'm thinking along the lines of using a high-speed camera to observe how gas flows out of the barrel when a pellet is shot.

Curious to see which crown shapes have the best experimental outcomes.

I imagine people have done this with powderburners, but maybe not air guns?

 

[GeneT]

I have not. BUT I recall a pretty involved study (with powderburners) that indicated that there really wasn't a difference as long as the crowns were equally good. (That, in and of itself, is a tall measure in these sorts of test) In any case, it was enough to convince me that there's no discernible difference. The explanation of the dynamics didn't really leave room for suppositions that airgun velocities would be any different.

It's a tough study to undertake as isolating the variables is difficult, but I don't think you'll find a "most functional" crown.

GsT

 

[Firewalker]

On its face, it sounds like an easy experiment: point the camera at the crown and shoot/press record!

Reality is that little if any useful data is collected due to focal blockage, smoke, fire and unburnt powder obscuring the whole crown.

One would need at minimum 8 high speed cameras watching 45° quadrants then all 8 videos stitched together on the same shot to be worth anything useful.

Shot to shot, powder burners spew out a BUNCH of debris.

Airguns offer other issues such as ghosting where defined lines and depth would be unknowable due to the ethereal vapor of just high speed air propulsion.

This also makes no mention of blow-by and how it would mask pitch and yaw.

Lots of footage out there, good luck.

 

[bigHUN]

Create a particles cloud around the barrel crown, like dense smoke or mist and shoot through that medium.
I am interested to see the details what is happening with the pellet skirt and around it ...