Handloads.Com Forum
Posts: 23 [ Displaying: 16 to 23 ] Pages: 1 2 [ Displaying Page 2 ]
Please visit the new forum to start a new thread
Handloads.Com Forum General DiscussionWind friction....does it cause melting in lead tipped bullets? | |
|---|---|
| Author | This thread is locked. |
| I dunno - I don't believe the theory either but while looking for a formula I came across an article that SEEMS to support the Colonel's position. I use a public terminal so I couldn't print it out for any lengthy study. It's at: http://www.snipershide.com/thinkblack/bbholespart3.html# DC | |
| Author | This thread is locked. |
| I read that article you note at length and noted several incorrect assumptions in it, two of which are a constant velocity and an ever increasing heat quotient but I believe the specific part you are referring to is this section. "During all this time of flight; the bullet, which got really hot after being blowtorched by the propellant gases, and further heated by bore friction, continues to heat up from air friction. This friction also gradually reduces its spin, and cuts down on its velocity. In many cases, the lead bullet core becomes molten and spews out through the ballistic hollow point to precede the more rapidly decelerating bullet jacket down its trajectory for a time. Gyroscopic forces deflect the lead outward, and at long enough ranges, they print on the target as a spiral emanating from the bullet hole (the gray comet)." (http://www.snipershide.com/thinkblack/bbholespart3.html, Greg Langelius 8-9-02) As I stated earlier, no matter what temperature the projectile is when it leaves the barrel, the friction with the air can only heat it up to a certain point and no further. Should the projectile already be hotter than this point, it will be “air cooled” back down to this point of stasis. Longer ranges would contribute to this cooling, thus the farther the projectile travels, the less likely it is to exhibit the proposed phenomenon. Again, all this assumes a constant velocity which does not occur, no matter what by brother says about his 300 Win Mag Browning A-Bolt. A fluid subject to gyroscopic forces behaves in such a manner that a hollow forms at its center running along the axis of the force. That is, if there is something to contain it, otherwise, it will simply spay off in all directions. Gravity is what contains the water of our oceans from flying off the planet, but whatever would contain the molten lead would have to also overcome the effects of gravity. Atomic cohesion is one possibility, but I do not think it is strong enough in this case to overcome the combined effects of outward inertia and downward gravity. For the sake of argument, however, I will assume it does, but then how does the core flow precisely back into the same hole it allegedly spewed forth out of, with the aforementioned hollow formed at its center? Not a very likely nor well thought out scenario. Not to mention the same gyroscopic forces would preclude the outward flow to begin with as the molten lead would be pinned, if you will, to the walls of its container and thus unable to flow out the centrally located hole. I have noted the “gray comet” mentioned on targets fired by hand guns at ranges as close as 25 yards and even closer, so there is another explanation for it other than the one put forth above. If indeed the core became molten, then the use of ballistic tip bullets would not stop this effect due to the thermal expansion properties of the lead core. That is, it would still heat to the melting point, and expand enough to upset the plastic tip greatly, even to the point of ejecting it from the projectile. Not knowing the exact composition of the tip, I cannot say if it to would melt when exposed to these alleged high temperatures, (in excess of 623 F to melt lead). This would be measurable on the target in two impact points. I can pick up these projectiles and hold them in my hand right after firing them if they are fired into a medium that facilitates recovery, such as sand bags, dirt or rubber tires. If they were at or near the melting point, I could never do this. I have fired lead bullets at close range into targets and had them leave the same “gray comet” around the impact hole but the recovered bullets show no signs of melting at all. I believe the “gray comet” is the result of the graphite added to most propellant powders in use today to make them flow better through meters and also to establish uniform bulk densities. It does appear to be graphite upon visual inspection of the target, and can often be rubbed off with the bare finger, leaving a stain similar to the one left by handling a number 2 pencil by its business end. It would be very easy for these particles of graphite to picked up all around the projectile during its travel through the barrel, having been deposited there by prior firings, as well as impressed upon the base at the initial moment of ignition. This concludes the today’s Physics lecture. | |
-- Bob -- Who really cares if a 500 pound laser guided bomb is accurate to within 9 feet? -- | |
| Author | This thread is locked. |
Thanks John. Guess that mathmatics minor finally came in handy.  | |
-- Bob -- Who really cares if a 500 pound laser guided bomb is accurate to within 9 feet? -- | |
| Author | This thread is locked. |
| Well, this topic has been properly beat into submission, thanks John ;-) Now we need to find another tough nut to crack... | |
DoD #2223 - OFCC #3122 | |
| Author | This thread is locked. |
| Hmmm, another thread to hash over...Which is better the 9mm or 45 ACP? No, that's been done to death everywhere else online and off line. Comparing PSI to CUP? Ah! I know...check back in General Discussions for the new topic... | |
John We’ll raise up our glasses against evil forces, singing; whiskey for my men, beer for my horses Molon Labe! | |
| Author | This thread is locked. |
How about why does this thread have well over 100 viewings when most of the others have less than 35? | |
-- Bob -- Who really cares if a 500 pound laser guided bomb is accurate to within 9 feet? -- | |
| Author | This thread is locked. |
| Just goes to show you never know what will interest people. Or almost never will, a thread about 357 Magnums or 45 Colts usually generate a lot of interest as well. | |
John We’ll raise up our glasses against evil forces, singing; whiskey for my men, beer for my horses Molon Labe! | |
| Author | This thread is locked. |
| Col Boddington is right but I don't have a clue as to why you can still hit things at long range. FWIW, I know a number of folks that have witnessed the phenomonon of very hi-vel .22's leaving a vapor trail for 50 yards or so in the right atmospheric conditions. I can attest that hi-vel bullets do burn flesh on contact, because I picked one up one day. | |
Does anyone know where the love of God goes, when the waves turn the minutes to hours? | Handloads.Com ForumGeneral DiscussionWind friction....does it cause melting in lead tipped bullets? |
Please visit the new forum to start a new thread
Posts: 23 [ Displaying: 16 to 23 ] Pages: 1 2 [ Displaying Page 2 ]
| Forum Stats | |
| 1,129 members posted 19,382 messages in 2,272 threads / 9 topics / 3 categories. |
|
| Please welcome our newest member : Jamesfromjersey | |
|
There are currently 58 guests and 0 members on the boards. | |
| BK Forum v.3.0 © 2001 - 2013 Black Knight Development. All Right Reserved. |