LugerForum Discussion Forums - View Single Post

MFC · 11-16-2010, 10:39 PM

Seiger and Patrick,
I'm not a reloader, so this may seem like a stupid question. The original rounds that measure .307, which is fired through a bore that measures .309, makes sense to me. As the bullet is forced into the rifling of the barrel, the metal that is displaced by the lands is forced into the grooves, forming a tight fit. If the bullet starts out the same or larger than the bore, the displaced metal can only make the bullet longer. Is this what is happening, or am I totaly off base? I really don't know, but it seemed odd to me to load a bullet larger than the bore. It obviously works, but wouldn't it also increase chamber pressure?

11-16-2010, 10:39 PM	#9
MFC User Join Date: Sep 2006 Location: Louisiana Posts: 1,237 Thanks: 183 Thanked 281 Times in 162 Posts	Seiger and Patrick, I'm not a reloader, so this may seem like a stupid question. The original rounds that measure .307, which is fired through a bore that measures .309, makes sense to me. As the bullet is forced into the rifling of the barrel, the metal that is displaced by the lands is forced into the grooves, forming a tight fit. If the bullet starts out the same or larger than the bore, the displaced metal can only make the bullet longer. Is this what is happening, or am I totaly off base? I really don't know, but it seemed odd to me to load a bullet larger than the bore. It obviously works, but wouldn't it also increase chamber pressure? __________________ Mike C. Last edited by MFC; 11-17-2010 at 12:18 AM.