|
The crown itself does nothing except protect the 90deg edge of the inner barrel.
With real rifles, the bullet is actually touching the inner surface of the barrel. As it leaves the barrel it needs to leave contact with the barrel around it's whole circumference simultaneously. Imagine that the barrel was cut at a 45deg from the longitudinal axis...the bullet would basically tip as it came out since one side of it get's "touched" for longer than the other side.
So if the barrel is simply cut off square, and doesn't have any burrs, then it's fine.
But people bump their barrels...so barrels are crowned (basically indented) so that the non-bullet touching edge of the barrel ends up dinged and the "ever so sensitive" inner surface remains pristine.
An 11deg crown is a convention...there was some thought that it was the ideal angle to have hot gases vent evenly/away from the base of the bullet resulting in it's maximum stability...but it's kind of hard to prove. Consensus from gunsmiths was that an 11deg crown was a good balance between easy of machining, durability and excellent consistent results.
A lot of this stuff is from a mix of field shooting and benchrest shooting...benchrest guys are pretty fastidious, field guys are more practical.
A clean 90deg cut off will work just as well in airsoft...because there is a whole other outer barrel protecting the inner.
I can't believe that any blow past forces at play in an AEG system would have any significant effect on AEG accuracy (which already sucks in comparison to real steel)...crowned barrel vs. not....as long as the cut is nice and the inner edge pristine.
|