It's axiomatic that .308 works better than .30-06 in a 20" barrel, whereas the .30-06 really likes full-length barrels to get up to speed. That makes sense, I think, since the shorter .30 cal cartridge uses less powder, but hotter powder.
What about when you neck it down?
How does a .243, .260 or 7mm-08 work in a 20" barrel, or shorter?
What about when you neck it down?
How does a .243, .260 or 7mm-08 work in a 20" barrel, or shorter?