View Full Version : scope mount drilling jig

December 5, 2005, 12:25 PM
I am confused over the different scope mount drilling jigs. Primarily in the requirement to remove the barrel. I purchased the Wheeler jig without realizing that the barrel had to be removed. My confusion is why it is not required in other jigs, such as the Forrester and B-Square? I understand the risk and consequence of drilling through into the chamber. However, if this is the reason, why is it not the same with the other jigs, or for that matter why is it not required when drilling and tapping for scope mounts without using a purchased jig??
thanks in advance

December 5, 2005, 01:29 PM
I'll hazard a guess while waiting for the guru's

Perhaps the small ring mausers may have less material to drill through, while large rings have a greater margin of safty.


Perhaps it is a liability issue with the maufacturer of the jigs. That particular manufacturer is not willing to accept that liability.

I have decided to go with a scout mount in leiu of the tradtional mount.

December 5, 2005, 08:40 PM
The wheeler jig uses a through hole that drills through where the chamber is located. You wouldn't want to drill a through hole into the chamber would you? I hate to try to use a bottoming tap to tap scope base holes personally. It shouldn't be too hard to find a smith close by that could pull the barrel for you or you could build or buy your own barrel press and receiver wrench. Not sure where you got it, but unless you have messed it up, you most likely can return it.

December 6, 2005, 05:03 AM
Welcome to our nightmare, DD!

What the others guys said. But I'll add that the Wheeler fixture will give better alignment of the screw holes than the others because it uses the receiver to center the jig. As most sporter conversions from military receivers start with swapping the barrel to change calibers it's only natural to drill the scope base holes after removing the barrel. No barrel on the action also allows the screw holes to be drilled completely through the receiver rings so you won't need a bottoming tap. Lastly, drilling the holes with the barrel in place will ruin the barrel and receiver threads if you decide to change barrels later.

December 6, 2005, 10:24 AM
fsherman66 thanks for the quick response and this is what I thought would be the main reason --- learned from that one. Also, you referred to a "scout" mount instead of the traditional --- ??????

cntryboy1289 thanks for the information, and you are right, and as I tried to indicate in my original post, I definately did/do not want to drill into the chamber.

mtnboomer --- thanks for the info and especially for your last comment, as I could not understand why it had to be a through hole as this should have been able to be controlled by the drilling depth.

December 6, 2005, 02:40 PM
Sorry I didn't notice it the first post. I use the wheeler jig yself and really like the simplicity of it. Like MtnBoomer posted, it uses the base of the receiver to locate it correctly.

James K
December 6, 2005, 05:35 PM
I can't see any advantage to removing the barrel prior to drilling and tapping a receiver. Yes, it makes it easy, but if a gunsmith doesn't know how to use the stop on a drill press and a bottoming tap he is in bad shape.

I don't understand Mtnboomer at all. I have drilled a whole lot of receiver rings with the barrel in place and have never yet drilled into the chamber or ruined the barrel. Also, I have never had any problem removing a barrel that has been drilled into unless the screw broke off in the hole.

AFAIK, all those drill jigs use the bottom receiver flat as the reference point if possible.


Harry Bonar
December 9, 2005, 08:09 PM
I agree totally, Jim
Harry B.

December 9, 2005, 11:26 PM
While I can drill and tap a reciever without the through hole, I just simply don't like to do it. I will do it when I need to, I just thought you were rebarreling the receiver. I still like the Wheeler the best and use it on through holes or non through holes.

December 10, 2005, 10:11 AM
Jim, Harry, and again cntryboy1289, many thanks for your comments, your thoughts and experience help more than you know. :) :) :) :)