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Bart B. · January 1, 2013, 09:36 AM

Bamaranger, I doubt your using a barrel with the same bore, groove and chamber dimensions used to base any printed data on; if your bore and groove diameters are larger, it'll shoot the same load slower. And you're not using the same lot of powder or primers either. And probably not the same neck tension on the bullets. To say nothing about how hard you hold the rifle to your shoulder when firing it as that alone can cause over 70 fps difference than someone else. Most noticable is the velocity spread between a given barrel and ammo fired with it hard fixed in a test fixture (as SAAMI does with a universal receiver; see my post below) compared to it in a rifle held by someone against their shoulder; that's gonna cause 100 fps difference; or more.

Therefore, a few hundred fps difference between a quoted velocity and what someone gets is as normal as sunrise every morning.

January 1, 2013, 09:36 AM	#6
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	Bamaranger, I doubt your using a barrel with the same bore, groove and chamber dimensions used to base any printed data on; if your bore and groove diameters are larger, it'll shoot the same load slower. And you're not using the same lot of powder or primers either. And probably not the same neck tension on the bullets. To say nothing about how hard you hold the rifle to your shoulder when firing it as that alone can cause over 70 fps difference than someone else. Most noticable is the velocity spread between a given barrel and ammo fired with it hard fixed in a test fixture (as SAAMI does with a universal receiver; see my post below) compared to it in a rifle held by someone against their shoulder; that's gonna cause 100 fps difference; or more. Therefore, a few hundred fps difference between a quoted velocity and what someone gets is as normal as sunrise every morning. Last edited by Bart B.; January 1, 2013 at 10:57 AM.