Re: Sleepy Bullets VS Sleepy Arrows(Archery)
Thanks for that excellent reply and explanation of the bullet yaw.
The only part where i can see your differences of opion are on the principles of precession, again i am not going to believe one persons views over another. This an area my friends and myself have discussed at length without any firm conclusions either way. I would like to see "mechanical" evidence, before i make up my mind.
Basically, Dr Kolbe says,if a bullet goes completely to sleep it will not track along its trajectory, point first which means it would strike the target at the same angle at which it was launched above the sightline,theoreticly producing an elongated hole.
I would have to see this before i believed it and think there are other factors in a bullets flight which we will never be able to investigate without very sophisticated high speed photography able to film the bullets complete flight(maybe this technology is already available?).
I don't know if you are aware, but the NRA of Great Britain (for what they are worth) have set specifications for the size of the 308 chambers used in the discipline of "Match rifle". This and poor handloading is probably the cause of bullet yaw.
On the other hand the more popular and formal "Target rifle" does not allow handloads, competitors must use "as issued" ammunition in competition. this is usually 7.62 sniper grade, which leaves a lot to be desired.
Again, rules govern chamber specs and barrels are specials that are up to .0015" smaller on bore size and groove diameter than standard 308" to suit this ammo. Custom rifles are built accordingly. This may again count for some bullet yaw.
The bullet "wringing" that you describe is very similar to the base deformation of soft lead bullets used in BPCR, which on exit from the muzzel get upset by gases escaping past one side of the bullet before the other.
I must admit i have witnessed this phenomena of relative group size whilst shooting BPCR with heavy for calibre bullets, although 400grn bullets grouped tightly at 100yrds, 520grn bullets did not, averging 4" to 5", these groups being the same at 300yrds, does this show unstable heavy bullets at less then 200yrds? or could it be that most of these haevy bullets are launched at the speed of sound or just below it from a 45/70.
your comments will be appreciated, thanks.