here's a decent review from the shooting time on the .22-250:
Locking on to loads
I will start with the 40-grain bullet heads. These are ballistically brilliant, however, bullets with thick jackets must be used rather than those with thin jackets, such as for use in .22 Hornet rifles or the Hornady SX range.
If you don't, the bullets will come apart as the centrifugal force of the rifling imparts its spin.
The Berger 40-grain MEF, Nosler Ballistic Tip and Hornady V-Max are good, and coupled with 36.25 grains of Hodgdon Benchmark powder, maximum load will yield a 4,021fps veloci