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Keeping myself busy tinkering in the shop I came across my notes in my Hornady reloaders manual. I double checked my measurements from 10+ years ago with my Hornady OAL Gauge and calculated that the rifling in my Tikka M695 .25-06 starts at 2.760" from the bolt face. I recall hearing that Weatherby also uses a long throat and they are accurate rifles. Is this long throat normal? I'm not complaining, I've always been VERY happy with the accuracy of this rifle. Just curious.

Here are the measurements that are giving me 1/2" & 5/8" 5-shot groups at 100 yards (all bullets Hornady)
Bullet C.O.A.L. Cartridge base Ogive to rifling jump
to ogive
--75gr V-Max______ 3.10" ________2.620" _________0.140" (established load)
--100gr SP ___ 3.10" ________2.635" _________0.125" (established load)
--117gr BTSP_____ 3.160" _______2.675" _________0.085" ( incomplete: this is where i left of in load development. Haven't finished, but looks promising)
 

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The Troll Whisperer (Moderator)
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My understanding is that Roy Weatherby had long throats in his chambers to lessen pressures by giving the bullet a "jump" prior to land engagement. Barnes Bullets always recommended a .050" set back from the lands for their monolithic bullets for the same reason. Not sure why Sako would have the long leade. Have never measured it in my L579 Forester .243 Win. I load to fit the magazine and assure they aren't jammed into the rifling.
 

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The standard throat is one bullet diameter, or .257 in the 25-06. It is rare to have a magazine long enough to seat to the lands.
Weatherby used the free-bore as pressure relief and it adversely affected accuracy in most of them.
 
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