An update -

I searched around and found 4 different 175gr .308 factory loads to test, and got out this weekend for a basic 100yd session to see what happens.

I tried Federal GMM 175, Lapua 175 Scenar-L, Berger 175, and Hornady 178.

Lapua shot the best 5-shot groups at 3/4" and 1". Federal and Berger both did about the same at 1 1/8".

The surprise was Hornady. Both 5-shot groups had flyers. I initially took the blame, but the second target had a similar flyer, with the first target at 2" and the second at 1 3/4". I had high hopes for the Hornady, as it has the highest bc of all that I tested. The Lapua has the lowest.

None of the groups were beautiful “cloverleafs”, with the best (Lapua) group being a mostly vertical string with all shots touching. The Federal would be the runner-up.

Not a definitive test, but good enough to get me started. By no means an expert rifle shooter at this point.

I have my LR class near the end of the month, with 600, 1000, and 1200yd targets. I'd be more confident going out to 800 with my set-up. I'm not expecting to hammer them in there at 1000, and depending on the weather/temp, it looks most will be transitioning to subsonic right about 1200.

We'll see. I don't expect this to be easy.

EDIT: Rifle is a Model 10 FCP HS Precision, 24" heavy barrel, with a SWFA 12x scope. Shooting prone off of front and rear bags.