Not hardly. The 243 Win has more velocity and energy than a 7.62X39mm. The 7.62X39mm is actually a little behind the 30-30 Win ballistically. If you are looking for an economical backup, look into getting yourself a H&R/NEF single shot in a decent cartridge like 308 Win, or 30-06. Better rifle than most surplus military arms and much better cartridges. Still inexpensive too.