Forums
New posts
Search forums
What's new
Articles
Latest reviews
Author list
Classifieds
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
burning exposed lead tip?
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="Konrad" data-source="post: 859454" data-attributes="member: 26549"><p>Coming from an elastomer molding back ground it strikes me as odd that designers would incorporate materials that would resist deformation from recoil in magazines and yet melt at roughly half the temperature of most plastics. Even nylons melt between 374 and 663F. Most thermoplastics begin to liquefy at around 350F.</p><p></p><p>It makes very good sense that the highest temperatures midrange would be about the center of the ogive. As in an airfoil the highest degree of frictional heat buildup is where the highest angle of incidence occurs and not necessarily at the actual leading edge. A spitzer meplat offers the least surface area for air friction to act upon whereas the ogive is the surface that actually does most of the work in forcing the air mass apart. I conceded that there is some degree of heat buildup at the very point of a spitzer bullet; however, I find it difficult to see a lead point being exposed to enough time/heat to actually become plasticized and be thrown off.</p><p></p><p>If indeed this happened all the time, one should see the "grey streaks" all of the time regardless of bore condition or spin rate. Merely using a "good" bore would produce little improvement.</p><p>One should also be able to see the grey streaks at a specifically defined air temperature and velocity (i.e. scientifically repeatable). </p><p></p><p>One can only wonder if the rough throats (and most probably bores) of the rifles you were using, combined with thin jackets and rapid spin rates contributed to damaged jackets allowing centrifugal forces to overwhelm the integrity of those projectiles and lead to their destruction.</p></blockquote><p></p>
[QUOTE="Konrad, post: 859454, member: 26549"] Coming from an elastomer molding back ground it strikes me as odd that designers would incorporate materials that would resist deformation from recoil in magazines and yet melt at roughly half the temperature of most plastics. Even nylons melt between 374 and 663F. Most thermoplastics begin to liquefy at around 350F. It makes very good sense that the highest temperatures midrange would be about the center of the ogive. As in an airfoil the highest degree of frictional heat buildup is where the highest angle of incidence occurs and not necessarily at the actual leading edge. A spitzer meplat offers the least surface area for air friction to act upon whereas the ogive is the surface that actually does most of the work in forcing the air mass apart. I conceded that there is some degree of heat buildup at the very point of a spitzer bullet; however, I find it difficult to see a lead point being exposed to enough time/heat to actually become plasticized and be thrown off. If indeed this happened all the time, one should see the “grey streaks” all of the time regardless of bore condition or spin rate. Merely using a “good” bore would produce little improvement. One should also be able to see the grey streaks at a specifically defined air temperature and velocity (i.e. scientifically repeatable). One can only wonder if the rough throats (and most probably bores) of the rifles you were using, combined with thin jackets and rapid spin rates contributed to damaged jackets allowing centrifugal forces to overwhelm the integrity of those projectiles and lead to their destruction. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
burning exposed lead tip?
Top