DMP25-06
Well-Known Member
Well , I will enter this "Arena" again with my theory , based upon reading numerous internet articles about the "Internal Ballistics" that occur inside the barrel , after the trigger is pulled , up to the moment that the bullet leaves the barrel .
I read information from : "Wikipedia", "NRA", "University of Utah", and other sites , and they all detail the same basic sequence of events .
Please bear with me , as I am certain that all of you know these events that I am describing .
Firing pin strikes primer , causing primer ignition that flashes through flash hole , which then ignites the powder inside the cartridge case which begins the "powder burn sequence".
As the powder begins to burn , it releases rapidly expanding gases that cause the cartridge case to expand against the chamber walls , thus sealing the case to the chamber .
The "Smokeless Powder" does not explode , instead , it is a "controlled burn", dependent upon choice of powders chosen , whether "Slow Burn rate" (Most Rifle Powders) , or "Fast Burn Rate" (Pistol and Shotgun Powders).
After the case has expanded against the chamber walls , the burning powder continues rapid expansion that forces the bullet out of the neck of the case , into the throat of the barrel rifling , thus creating greater pressure . At this point , the internal pressure is at it's highest level .
As the bullet begins movement through the barrel , it enlarges the space in which the powder is burning , thus allowing a drop in internal pressure .
However , the mass of powder inside the cartridge case is being pushed out of the cartridge case , burning more , continuing to create pressure as the bullet travels through the barrel , increasing the velocity as it travels .
The longer the barrel , the more powder burn , the greater the velocity .
But , the longer the barrel , the more difficult it's usage , so barrels are chosen in usable lengths , for the chosen application , whether Hunting , Target , or Combat .
The bullet is being propelled by this pressure wave of burning powder , until it exits the barrel followed by the unburned powder ( 1% unburned powder is the closest to complete-burn of the powder charge , that I found listed in any papers that I read ).
The muzzle flash is created from the escaping burning gases , and also the unburned powder that was forced out of the barrel when the bullet exited the muzzle . These unburned granules of powder will then be ignited outside the barrel by the fireball of burning gases .
So , my theory is that the burning gases , from the powder-burn , never contact the bases of the bullet , as I have observed from viewing the bases of the few Nosler Partition bullets that I have recovered from animals .
Now , to address the thought of molten lead inside the bullet's jacket ?
If the super-heated burning gases , which can reach 5,600* F. do not actually touch the base of the bullet , or , even if they did touch the bullet , it is not for a long enough time to raise the temperature of the lead to a melting point .
A bullet with a muzzle velocity of 3000 FPS , traveling 24" , traverses that distance in 0.0006667 seconds . So , when shot through a 24" rifle barrel , the bullet would exit the barrel in approximately 0.001 (1/1000th) of a second after detonation . Hardly enough time to change the bullet's temperature .
Friction from riding the bore would induce more temperature to the bullet than either powder burn , or air-friction when in flight .
DMP25-06
I read information from : "Wikipedia", "NRA", "University of Utah", and other sites , and they all detail the same basic sequence of events .
Please bear with me , as I am certain that all of you know these events that I am describing .
Firing pin strikes primer , causing primer ignition that flashes through flash hole , which then ignites the powder inside the cartridge case which begins the "powder burn sequence".
As the powder begins to burn , it releases rapidly expanding gases that cause the cartridge case to expand against the chamber walls , thus sealing the case to the chamber .
The "Smokeless Powder" does not explode , instead , it is a "controlled burn", dependent upon choice of powders chosen , whether "Slow Burn rate" (Most Rifle Powders) , or "Fast Burn Rate" (Pistol and Shotgun Powders).
After the case has expanded against the chamber walls , the burning powder continues rapid expansion that forces the bullet out of the neck of the case , into the throat of the barrel rifling , thus creating greater pressure . At this point , the internal pressure is at it's highest level .
As the bullet begins movement through the barrel , it enlarges the space in which the powder is burning , thus allowing a drop in internal pressure .
However , the mass of powder inside the cartridge case is being pushed out of the cartridge case , burning more , continuing to create pressure as the bullet travels through the barrel , increasing the velocity as it travels .
The longer the barrel , the more powder burn , the greater the velocity .
But , the longer the barrel , the more difficult it's usage , so barrels are chosen in usable lengths , for the chosen application , whether Hunting , Target , or Combat .
The bullet is being propelled by this pressure wave of burning powder , until it exits the barrel followed by the unburned powder ( 1% unburned powder is the closest to complete-burn of the powder charge , that I found listed in any papers that I read ).
The muzzle flash is created from the escaping burning gases , and also the unburned powder that was forced out of the barrel when the bullet exited the muzzle . These unburned granules of powder will then be ignited outside the barrel by the fireball of burning gases .
So , my theory is that the burning gases , from the powder-burn , never contact the bases of the bullet , as I have observed from viewing the bases of the few Nosler Partition bullets that I have recovered from animals .
Now , to address the thought of molten lead inside the bullet's jacket ?
If the super-heated burning gases , which can reach 5,600* F. do not actually touch the base of the bullet , or , even if they did touch the bullet , it is not for a long enough time to raise the temperature of the lead to a melting point .
A bullet with a muzzle velocity of 3000 FPS , traveling 24" , traverses that distance in 0.0006667 seconds . So , when shot through a 24" rifle barrel , the bullet would exit the barrel in approximately 0.001 (1/1000th) of a second after detonation . Hardly enough time to change the bullet's temperature .
Friction from riding the bore would induce more temperature to the bullet than either powder burn , or air-friction when in flight .
DMP25-06
