Relax, it happens and I've done it too - there are fixes. If you are at the ramrod drilling stage then you must not be too far along with the build. So, don't do anything just now while you ponder the following...
Consider going ahead with your stock shaping before returning to the RR breakout problem because by then you'll really know how far off the hole is. Also; in the barrel channel you can drill some 1/16th holes to check where the RR hole is in relation to the barrel.
Options; One - adjust your ramrod channel now and drill the hole to an acceptable depth. Two - eventually dig out, expose, the RR hole, deepen it, and glue a length of wood into the forearm (try and match the grain with some scrap from your profile cutting), or, three - plan on a wear plate, which is something you'll want to inlet toward the end of the build. If you decide on a wear plate remember that it too will be inlet so allow for that in your calculations; in other words you may have to excavate the RR channel a bit under the plate.
This is a learning opportunity, so have all the fun you can.
dave