Barrel replacement

[Steve N]

Do the rules allow a replacement barrel to be longer and a different twist than the original factory barrel
For example could a 22 inch 9 twist 223 barrel be replaced with a 26 inch 7 twist barrel?
Steve.

[Barry Davies]

The rule (s) relating to barrel replacement simply say any barrel of max. length 26"and max profile of heavy varmint.
So in answer to your question -- yes

[Blindbat]

What about caliber? Does it have to be a caliber originally produced for the action or can it be any caliber including wildcats?

[Barry Davies]

Rules do not specify replacement barrel is to be the same calibre as original.
Any calibre can be used up to the limits of allowable muzzle energy for that particular range so one would guess that applies to replacement barrels as well.