Same observation as TT, even if it was with Hornady superformance loaded with Interbond.
Some month ago, being short of handloads and having opportunity for 600m and more shootout i got three superformance boxes of 300 Winchester magnum loaded with 180grs IB at my friends shop. Shooting them in a new model German "sniper/tactical rifle" made some chrono, zeroed at 200m. They were almost as good as match cartridges.
Going through the Sierra software i determined a trajectory to 600 and 800m using velocity noted and Hornady BC. At 600m 40 bullets on 40 were in the center of an 8x7 inch steel plate. Impact was very interesting to say the least...At 800 the last ten were in the 10in steel gong. wind was around 8 to 10mph, not constant and turning sometimes.
When i don't want to handload and because my friend give me very good price i use them to practice a bit.
Had the same accuracy with factory 270 Winchester IB.
May be my rifles are not finicky, may be i was lucky, but nothing to blame on the factory IB i shot.
Never hunted with.
Dom
