Load development for newbie

[remtac14]

Hi all. I am new to the forum and new to reloading (not shooting). My father in law really stirred my interest in accurate rifles and I have since turned two factory rifles into sub MOA guns. One is a model 700 sps tactical .308 12" twist w/20" bull barrel. I changed the stock to a b&c medalist with aluminum bedding block. I then glass bedded the entire action. The other rifle is a 700 adl 7mm RM with laminate stock that I pillar and glass bedded. The 308 will consistently produce .25 to .5" groups shooting factory Hornady 168 amax and also cheap 165 Federal fusion ammo (hunting bullet that shoots great in this rifle). The 308 has also produce 1" to 1.5" groups at 300 yards (furthest I've tested). Now for the question...

I am wanting to develop a load based off factory hornady amax loads since they already shoot good. I have bullet comp. tool for the 308 so is it safe to say that I can just seat bullets to the same base to ogive length as the factory loads and then figure out the optimum charge wait? I will be using full length bushing dies if that matters. I will also be developing some loads using the 165 sierra gamekings. I plan on using fed GM primers along with either hornady or federal brass. Once I saw how well the two factory loads shot I bought several boxes of each at the same lot number. Opinions and advice is appreciated...

 

[remtac14]

I might also add that when I chamber the hornady factory ammo it is considerably harder to close the bolt. I also painted the bullet with a sharpie, chambered the round, and you can clearly see the land marks really close to the case mouth. I also did the same with the federal fusion ammo and can't see land marks. Both factory loads shoot great. I am just trying to figure out if I should start out .010" jammed or .010" off the lands.

 

[Rattler56]

If you chamber a shot once pice of Hornady brass is it still tight ?

 

[remtac14]

If you chamber a shot once pice of Hornady brass is it still tight ?

Its firm..not tight. It is about the same firmness as the federal fusion once fired ammo. I think it hard to close bolt before firing because it is jamming the amax to far into the lands. Both brands of fired cases have about the same firmness when trying to close the bolt.

 

[Rattler56]

I try to load just kissing the lands to start and the brass sounds a little long if its firm, I,am not good
at explaining how it should feel some one else can jump in on that.
You could seat one of the amax's down a little more to see if it gets better, your reloads should slid in
just like factory ammo, maybe a little tighter, measure your once shot and resize it a .001 to .002 from your reading then before
you seat the bullet try it in the chamber.