Hello I have a Savage model 840 in 30-30 I know there have been several models of this rifle but I'm curious if there is any compatability between the stocks of the 340, and the 840. The photos I've found online they look just about the sa,same, but I can't find any information on interchangeability of the stocks or any differences. Boyd's makes a stock for the 340 but not the 840. Amy information would be greatly appreciated. Thank you.