Originally Posted by wpwarren
I sold my 7mm mag and bought a .300 win mag savage with the drop floorplate. I measured the length of the magazine compartment for the gun and and have a total length of 3.47 in. I am curious what overall length you are loading you guys are loading your .300 win mag ammo to. Details that would be helpful would be overall length and what bullet and weight. I will have my tool to measure chamber length to the lands in a couple days and would like to pick up some bullets based on what will fit into my magazine and hopefully be able to be seated into the lands.
If the rifle is for hunting start your load development with the longest length you can yet still fit the magazine. Purchase the bullet for what it will be used for (hunting target). All reloading books show the loads for the 300 WM using the COAL of 3.340 so most all bullets will work at that length.
Just remember when moving the bullet deeper into the case or moving it towards the lands there will be a pressure change. Any time you put the bullet tight against the lands there will be a spike in pressure of about 7,000psi so be aware of that. Start you load workup low when getting in close to the lands and have the tools to know exactly where the bullet is in reference to the lands.
With your mag at 3.470 I would start my load development somewhere around 3.400-3.450 (a judgment thing)and work back from there. Good luck.