[/quote]MD
So could you take a WOG and venture what a 1/2" deer rifle with a flat base might do with a BT? 3/4" at 100? I'm trying to get a feel for the difference on average for a hunting bullet out of an accurate rifle. [/quote]
No, can't make a WOG because individual rifles and bullets vary so much.
Have had boattails average less than 1/2" at 100 yards from a "deer rifle"--and that's 5-shot groups. not 3-shot, from a rifle that weighs less than 8 pounds with scope. But it's a custom 6.5 PRC built by Charlie Sisk, with a 1-8 twist Lilja barrel. But I have never tried any flat-based bullets in the rifle, because they don't make much sense in a rifle like that. Maybe they'd shoot 1/4" groups.
The first super-accurate "deer rifle" I ever owned, however, was a Remington 700 ADL I epoxy-bedded/free-floated in the mid-1970s. (In fact, it may have been the first "glass" bedding job I ever did.) It shot most bullets well from the get-go, but by far the most accurate handload turned out to be the 150-grain Hornady Spire Point with around 58 grains of H4831--which at the time was still the original mil-surp powder. It would regularly put 3 shots into 1/2" or less at 100 yards, and the only time I tried it at 300 four shots went into 1-1/4". I shot four rounds because that's what I had on hand--and that was with a 4x scope.
It eventually turned out the superb accuracy was partly because of other factors I didn't understand at the time, including what was probably a super-consistent batch of bullets--though it was definitely repeatable.
But the tendency of flat-based bullets to shoot more accurately out to 200-300 yards had been well-established in benchrest shooting. However, unless you just want to punch small groups in paper with your deer rifle, it's irrelevant at ranges out to 300 yards--or even farther.
