Where there's smoke there's??????

[Vern]

This is going to be the first of hopefully several questions that might make us think.
Unless that is someone has the answers with facts to prove it.

Question:
When you watch rifles being fired in ultra slow motion from a bench most of the time (not all) you see smoke come out of the barrel before the bullet. Why and what effect does this have on the bullet following it?

Could the smoke/gas be caused by the powder gasses bypassing the bullet until it was able to reach the lands. It would seem that this would be more prevalent in sami chambers.

However I wonder about that with benchrest chambers because jump or no jump there is usually a short enough leap that the bullet should reach the lands before the gas leaves the case because we can jam.

Does anyone have any slow mo of benchrest shooting so as to be able to determine this aspect?

 

[Charles E]

Get a copy of Vaughn's Rifle Accuracy Facts. Both the spark photos of bullets/gas exiting the muzzle, and the explanation.

 

[mwezell]

Jump or jam, you'll have some leakage until the bullet obturates to the bore and creates a seal. Either way, it'll be over before you can say grasshopper.--Mike