Re: Out of spec chamber, or OAL help
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: coyoteduster</div><div class="ubbcode-body">Ok, so I have a sendero in 300 win that I have not been able to get the type of accuracy out of that I expected (around 1.25 inch or so average). I decided to measure my overall length by drawing on the bullet with black sharpie and chambering it until I did not see any marks. For the bullet I am using (178 grn Amax) I came up with an oal of 3.50. The book lists a OAL of 3.340. This comes out to be a difference of .16 of an inch. This seems huge to me, but I don't know. What do you guys think? Is my method of checking sound. Does this chamber seem to be out of spec or is this about right for a factory 700? Any help would be appreciated. </div></div>
Coyoteduster,
Just a little background on the 300 Win Mag. When Winchester developed the 300 Win Mag in 1963, there was only one size of Win Model 70 action. For 308's or shorter, they used spacer blocks. For 300 H&H and 375 H&H, they removed part of the receiver rings fore and aft, shortened the boltstop, and used a longer (3.60") mag box.
All others, for the 30-06 length cases, and the "short mag cases", the mag box limited the cartridge OAL to 3.340".
<span style="font-style: italic">NOTE: In 1963 Short Mags were the 264 Win Mag, 300 Win Mag, 338 Win Mag, 458 Win Mag., not the WSM's of today.....</span>
Ruger 77 long actions are also on the short side, and limited to 3.340", among others.
That's why the book even today the book length on the 300 Win Mag is 3.340". However, Remington 700 long actions will accommodate rounds up to 3.70". So you are not restricted to an OAL of only 3.340".
So how long should you load it? That's up to you, but just don 't jam it into the lands, and you will be OK.
Bob