Zonie has a good point about swamped barrels and staples. I wont use them, I have seen a swamped Rice barrel rendered useless because of them.
The rear lug was OK but, the front 2 where a problem. Not because they were drilled too far but, because when setting the staple the punch dented the inside of the barrel.
This gun was a kit from one the top suppliers that a guy had bought and then changed his mind about being able to build. He had the supplier cut the dovetails for sights and install the lugs because he thought it was more that he could handle. He contacted me to do the build and we struck a deal to do it as a “I’ll help him so he could learn about gun building kind of thing”. He lived about 30 miles from me and it worked out real good.
Well, he did most all of the work and ask questions at the right times and came up with a very nice rifle over the course of ½ a year. During finial assemble he mentioned that as every now and then he would wipe the bore and felt bumps as the jag passed two spots in the bore. I dropped a light gown the bore and sure enough two small bumps under both forward lugs. By the way the barrel was a .50 B weight 42”. I happen to have an account with the supplier and a phone call got a new barrel on the way.
The fellow that owns the rifle knows how to cut dovetails now and the rifle shoots perfect to this day.
If you go to Rice’s website you find a warning about how to attach lugs to their barrels.
Bruce Everhart