rkittine said:
Is the only reason that certain calibers are considered Barrel Burners, because they normally use, or need to use for accuracy high powder charges and high velocity?
A 6.5x47 appears to not be a barrel burner, while a 6.5x284 does. If one was to load these both for the same velocity (regardless of accuracy anticipated or realize) would they have the same or similar barrel lives or is there something else here I am missing? Load a .25-06 like a .257 Roberts etc.
Bob
To answer your question directly...
If you take a larger case, in the same bore size, and load both to the same velocity with appropriate powders, the larger case's barrel will NOT burn as fast, because it can develop the same velocities as the smaller case... with lower pressure/temperatures.
If is the peak pressure, temperature, and flame duration, that determines the rate the barrel burns.
Also, a barrel will burn out faster with heavy bullets, than light bullet because the flame duration for heavier bullets is longer.
"The larger the expansion ratio the faster it will burn barrels."
The expansion ratio has nothing to do with it.
The 22 Hornet has a humongous expansion ratio (20:1), and barrel life of 60,000+ rounds... the .221 FireBall is good for 30,000+... and the expansion for the 458 Winchester Magnum is 15:1 and you cannot burn out a 458 WM.
The 264 WM has an expansion ratio of 4.8:1 and will eat a barrel for breakfast (ask me how I know that).
Lyman manual is 35+ years old, with only a few cartridges added once every 10 or so years. (Look for the 6.5x47 in 2019).
The text is antique. There are no serious hand loaders at Lyman now - the good ones left in 1971, after Leisure Group took over, and were never replaced when Leisure Group left in 1978.
As it stands now, there are better manuals around.