COL question

H

hubee_7j

Active Member
Joined
Nov 1, 2009
Messages
37
Location
Cross Timbers MO
If the COL is shorter (bullet seated deeper) will the velocity be more or less than if its not seated as deep ? And why ? Also I'm shooting a 308win with 168 amax how far off the lands should I be. Right now it looks like .115 of an inch is that ok?? Thanks for any input!
 
B

boomtube

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Oct 8, 2007
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1,595
Location
Mountians of SW NC, near Asheville
"If the COL is shorter (bullet seated deeper) will the velocity be more or less than if its not seated as deep ? And why ?"

It depends on several variables, including powder burn rate, bore size, bullet weight, case volume, how far off the lands you are seating. Other than that, it's no problem. !! :D



"Also I'm shooting a 308win with 168 amax how far off the lands should I be. Right now it looks like .115 of an inch is that ok?? Thanks for any input!"

If it works, it's good. No one can honestly tell you how far off the lands you should be. ??
 
woods

woods

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Joined
Jun 4, 2006
Messages
995
Location
Shangri-La
All other things being equal, the pressure will be less and thus the velocity will be less the deeper you seat

pressuregraph.jpg


Barnes did some tests

http://www.barnesbullets.com/resources/newsletters/september-2007-barnes-bullet-n/

Pressuregraph1.jpg


Down at the bottom of this page Hornady has some info

Internal Ballistics - Hornady Manufacturing, Inc


Also IME, velocity decreases with increased seating depth.
 

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