Proper name of parts

[dynafit]

Please tell me what the proper names are for the parts needed to shorten a Rem721 blind mag feed to better handle short action calibers. No idea if I've described this properly. I bought an older Ruger M77, chambered in 22-250, which has an insert in the mag well to decrease mag length as well as a short action sized shell follower. Just want to do the same for the Rem721.
Thanks for the help.

 

[Bret GRAVELINE Graveline]

I would call it a mag box spacer, spacer block, I don't beleave anyone ever made one for remington, however its not a problem for a good gunsmith, i used to made them all the time back in the day. A block of aluminum and a couple of allen head flat screws will do the trick

 

[dynafit]

thanks for the info. I just checked Brownells and they seem to have nothing.