Which stock round? Federal GM308M2 or Hornady 8077

[NightmareArmory]

Hi,
I have a new Remington 700 SPS Tactical 20" .308
It is mounted in a MDT TAC21 chassis with Primary Arms PA4-14XFFP Mil/Mil scope, Magpul PRS butt stock, Harris bipod among other goodies. I plan on using for benchrest and prone target shooting at 100yd indoor min distance and 888yd outdoor max distance.

I am in the process of purchasing ammo for breaking in the rifle and wondered if I could ask for input on the (2) rounds I found available that seem to be high quality off the shelf ammo. I currently do not have the ability to do reloading.

The Hornady 8077 at 178gr (3 grains greater bullet weight) has significantly better specs over the Federal GM308M2 from what I have found
Muzzle energy is 3043 ft lbs vs 2627
Muzzle velocity is 2775fps vs 2600

Do I need to be concerned with this difference if they are close to the same cost per round?

Thanks for your input!

 

[Bart B]

I wouldn't wast barrel life breaking it in; that's a waste of time in my opinion. A given ammo lot of one may well shoot more accurate than the other.

Shoot 20 shots into a single group with each, then pick the one that's most accurate. Any less and the credibility of the group representing accuracy to a 90% level starts dropping. 5-shot groups are about 30% credible.

Shoot them at 2 minute intervals so barrel heat does't make it bend; very common with commercial rifles. If it does walk shot impact as it heats up, that can usually be fixed by turning the receiver face as it's held in a mandrel in a lathe square with the barrel tenon thread axis then shimming it to clock in for headspace. Any 'smith worth his business card could do that very easy.