Found a couple of interesting vids .

[Harter66]

https://youtu.be/8c3aHHG7_Q0
*https://youtu.be/OmUThggIfVo . This 1 is very interesting as there is flash in front of the bullet .
*https://youtu.be/spAd_iO1-Z4 .* another with flash in front of the bullet

I just thought they looked cool, the last 2 are jacketed of course and in the past there has been some discussion about gas seal and escaping gases. At least in the last 2 it shows a full muzzle flash well ahead of the bullet.

[Hick]

Fascinating

[Hick]

Harter66

Back again with a question (I had to think awhile before it dawned on me): In the first video, even when I slow it down more, I cannot see the bullet. In the other two the flash clearly comes out ahead of the bullet. What about cast? With or without gas check? I'm wondering if this would show how the sealing effect of the base works with cast.

Walt

[Harter66]

I haven't found any cast specific flash videos . I think probably the ROA is as close as any I've seen to a cast flash video.
Our goal is to seal the grooves before the bullet clears the case .
With past videos the anti agreement has been around the gases being actual charge gases or bullet wake gases . This actual shows clearly the hot gases ahead of the bullet. I'll have to look at the ROA video on the big screen and see if I can spot the ball..

[popper]

IMHO those vids are misleading. I see the bullet in all, revolver has some 'flash' before the bullet, most after. I think it's luminescent air proceeding (shock wave generated), not powder gas. The stuff a flash hider is supposed to eliminate. Revolver has burning powder after the boolit passes and is SLOWER.

[Harter66]

I guess we need million frame per second cameras and be able to look 800,000 frames in stop frame 1 at a time and know every detail . Physical, pressure and density altitude measured and molecular density of the atmosphere, the precise make up of pre and post projectile gasses probably temp of gasses pre and post bullet and some means of measuring potential, real and actual pressures .

I must have watched the ROA 20x and the flash to exit was so fast I never saw the ball/bullet exit .

[popper]

It's ~ 0.02^00 sec, hard to catch.

[Harter66]

That's 55.555556 seconds of video at million frames per second played back at 60 . 3 special filter cameras could sort out heat and gas signatures and that high rent pressure lab ..... shouldn't cost over 10k for a professional film crew to set it up and capture 30-60 rounds .
10 shots each for cast ,jacketed and copper.