I am getting ready to build a 6.5-300 WSM
and am wondering what you guys have done for case prep. I bought 300, of the 300 WSM brass all of the same lot to be necked down. I bought the Hornady dies in 7mm WSM
to do the first necking down the 300WSM brass. Then I will use the Lee 6.5-300 WSM die to get my final neck dia. I also noticed that the neck OD after using the Lee die with no mandrel in it was .282 and the ID was .242 WTF.. That is WAAYY Too small. I know most dies size the neck more than it needs to be and then the expander button opens it up again, which if you do some measuring that is where you get your case stretching at. I have been honing the neck on my dies to give me .003 neck tension .003 Dia. smaller than bullet diameter. Then I sand the expander ball to be .004 smaller than bullet diameter. so if it touches on case extraction that the case necks need some attention.
There isn't a benchrest or inline seater die available for the 6.5 300. So I am going to make a sleeve to put in the 7mm inline seater die for the 264 Dia bullet to keep the bullets going in straight.
I noticed the necks started out at .013 thick and after sizing to 6.5 are .016 thick. Do you guys turn the necks and to what thickness and what is your chamber neck dia.?
I am also going to anneal them after forming.
Maybe I should of started out with 270WSM brass. From what I read and was told the 300's had longer necks but after necking down they are both the same.
Thanks for any tips.
Also what are your favorite loads.