Re: 5r question
There are no mods required.
The 5R uses the exact same action as any other remington (SA for .308/.223, LA for .300 WM). It uses the exact same barrel profile as any rem varmint/sendero.
My feeling is that since they are advertised as using the "same barrel" as the M24, there was a mistaken belief that the profile was the same as the M24 and no one has bothered to correct it.
From the stocky stocks website for the B&C A5:
-fits factory hinged floorplate and Wyatt's Detachable System;
<span style="color: #FF0000">-Cut for the standard Rem #3 Varmint / Tactical barrel</span>;
-easily modified for 5R mil. spec. and most other heavy contours;
-includes the 700 SPS, XCR, VTR Varmint and Tactical type rifles.
The 5R <span style="text-decoration: underline">IS</span> a standard varmint/tactical contour.