I hope that this hasn't been covered previously and I apologize if it has. I checked a hundred or so 270 threads, and didn't find this particular problem.
The ammo has been never fired Remington, fully sized, flash holes deburred,and primer pockets squared up.
The bullets are Sierra Pro Hunter 130 grain.
I have used two different powders. H4831sc, and R22. All primers have been Federal Large Rifle. The rifle is a Marlin XL7 with a work over by Neil, our resident Bigfoot Master Gunsmith. It's in 270 Winchester,and mounted with an inexpensive Nikon Pro Staff 3X9 variable Scope.
I have been away from reloading for about twenty years due to a rather serious Bow Hunting addiction... I consider myself to be a rookie that knows just enough to be dangerous!
In any case, I started out using 130 grain Federal Power Shok as a control. Results were as follows, after zeroing. 100 yards, three five round groups measured roughly 3/4".
Best accuracy load from this rifle? Was an astounding, to say the least? Three sets of five rounds. 0.0300, all signed by witnesses. Certainly, the best that I have ever shot. ( 270 bullets are 0.277" diameter) That was R22 at 56.6 grains, once fired Federal brass, Federal Large Rifle Primers. The bullets? Sierra MatchKings. That's a pretty tough baseline standard... I do not expect hunting ammunition to be anywhere near that performance.
I am getting? Let us say frustrated...
This post is already pretty long...
Best load so far using H4831 is Seven inch groups at 56.7 grains.
Best loads so far using R22 are 58 grains at three inch groups...
These are not acceptable hunting loads.
Accubonds are at 1/2 inch in both 130 and 140 grains.
I love Sierra, but I as a Hunter owe it to the game that I hunt a clean kill.
Any assistance will be appreciated.