Author Topic: ideal bullet diameter (Read 1485 times)

kirkwhitaker · « **on:** February 13, 2003, 11:25:36 AM »

what is the "ideal" bullet diameter for a pp bullet. if you have a gun that is say a 6.5 mm/.264 cal. lands would be .256 and grooves would be .264. for a normal cast bullet you would want a bullet .002 over..so it would be .266 or so. would you ideally want a patched bullet to be about the same or slightly bigger patched?...so if you were using .0025 9 lb onion skin your starting bullet size should be in the range of .257...is this correct? so for my 375 win...have sized a .379 down to .370 and patched back up to about .378 (it shrank .002)...does this seem about right...if i patch with .004 20 lb paper it would end up at about .384..which is way big...
thoughts please...
kirk

Kragman71 · « **Reply #1 on:** February 14, 2003, 06:53:38 AM »

Kirk,
All of my success with paper patching is with 30 caliber bullets,so you will have to interpolate the info for your caliber.
My bore (lands) is .300,and my bullet is .3013.
A double wrap of #9 paper increases the diameter to .308(adds .07).
I'm not sure of the groove diameter of my rifle,but it is at least .308,because the paper is converted to confetti on a fired bullet.
Almost everyone that I ask,suggests that the lead core should be .001 or .002 over the bore diameter(lands).
No one seems that certain about the diameter of the patched bullet.
I suspect that a patched bullet with a diameter greater then the groove diameter of the barrel should be wrapped in the direction of the twist in the barrel.That will tend to unravel the paper.
I do know that,in my 30/30,the direction of wrap makes no difference.
Frank

kirkwhitaker · « **Reply #2 on:** February 14, 2003, 08:13:50 AM »

i had read about patch direction and size. patching the direction of my twist. like i was saying...377 is my diameter on these...miked a recovered bullet...369/375...these are .370/377...ought to be close...

Lead pot · « **Reply #3 on:** February 25, 2003, 05:30:14 PM »

Hi All.
The way I do mine is>for black powder I make them .003-.004 smaller than the bore diameter.
For smokeless they are .001 larger than the bore diameter.For harder bullets they should be a little larger.I use a mix of 40-1 lead tin for all of my pp bullets.
I wrap all my patch in the direction of the twist.
What do you guys use to keep the paper to hold together??I like to mix a little flour in the water. Lp.

Kragman71 · « **Reply #4 on:** February 26, 2003, 04:16:05 PM »

Lead Pot,
Although I believe that saliva(from the mouth)is probably best,I ue plain water to hold the paper to the bullet core.
I keep a sponge moistened by keeping it in a shallow plastic dish that has water in it.
When I inspect the newly patched bullets,I use saliva to "touch up"any loose ends,usually arount the tail. This amounts to about 10% of the bullets patched.
Frank