The old yellow/red box were advertised at 1335 fps. for 40 gr and 1365 for 37 gr hp.... (sounds a little optimistic to me) From an old 1967 Gun Digest. If I'm looking at the right one. No barrel length specified.
I believe you're looking at the right one. Western Super-X was hi vel ammo. I could be wrong, but weren't old factory .22 RF loads tested in 26" barrels?
OP: The only guns I wouldn't shoot that HV stuff in would be pre-war things made before the introduction of HV ammo in the early 30's. While a lot of them would digest it ok, a lot of them can be battered by using it. (Example: pre-1932 Colt Woodsman.) Pretty much any decent gun made post-war would be up to the task, pistol or rifle.
