Some opinions on swamped barrel profile symmetry?

[Larry (Omaha)]

My son in law is building his first rifle from a blank. He has a 42" name brand C weight swamped barrel. He is not fitting wood to the lower diagonals, but making the channel flat. His choice. That is not the issue. The last two or three work sessions he has been using lamp black for final fit. Yesterday, when replacing the barrel in the channel, he accidentally put the barrel in upside down. (No tang yet) The result was a surprise to both of us. I actually thought the wood had warped because I did not realize he put the barrel in upside down. Now, here is the question: Can a swamped barrel be that far off of symmetry and still be considered a decent barrel? Is it is somewhat typical to have them out of symmetry? The photos show (left), with the barrel in correct, (right), the barrel is a strong 1/8" hanging over the side of the channel. It just would not go in. The barrel channel is nice and straight.
I have heard of lots of barrels that were not bored centered, but never heard of this issue. Thoughts please?

 

[Col. Batguano]

It should be symmetrical. Sight down the barrel flat to see if you can detect something of a bend to it. I got one that was bent one time from a "name brand" barrel maker. I never discovered it until I went shoot it. It just never occurred to me to look for that.

Who is the barrel maker?

 

[billraby]

That flat barrel channel is likely to cause some really big problems when it comes to shaping the fore end. Those bottom corners are likely going to end up going right through the side.

 

[Larry (Omaha)]

That flat barrel channel is likely to cause some really big problems when it comes to shaping the fore end. Those bottom corners are likely going to end up going right through the side.

Thanks, I know!
Tell that to my SIL

 

[user 34300]

Thanks, I know!
Tell that to my SIL

Not to pile on but, he may have ruined the stock. It can not be inletted square. IF possible he needs to do a good job by going deeper into the blank. Some people need to make mistakes for themselves. It may be time to step away from the project if he doesn't listen.

Some originals were inletted with a round bottom. IT is sloppy but works.

 

[rich pierce]

Barrel may be bent. So far you’ve tried setting it in correctly and upside down. Try the other 6 possibilities and see what you learn.

 

[Robby]

Run some patches down the bore and shine it up, look through it, if its bent you will see it. If its not, It doesn't take much deflection to throw a barrel off that much over its entire length, stick a .010 shim in the channel at one end and see how much that throws it off. I find swamped barrels that are not perfectly symmetric all the time. The square channel is a bad idea, if you have enough wood I would take it down with a round nosed scraper, common in original rifles.
Robby

 

[Col. Batguano]

Since you have squared off the barrel channel, Bill Raby is correct. A V-shaped fore end may not leave you enough wood for the integrity you need when you are shaping your fore end. The good news is that you probably have more web thickness than you actually NEED. That's a classic new builder mistake. Too thick of webs. If you are lowering the barrel in the barrel channel that will get you the wood you need to make a more proper 45 degree angle on the oblique flats for wood contact. Just don't lower it with more SQUARE inletting! Many slim (swamped barreled) guns actually get built with nearly ZERO web thickness at the breech, and 1/8" thickness at the muzzle. Your barrel lugs will probably break through to the RR channel, but that's not a big deal.

You can also help yourself by decreasing the barrel flat coverage with the fully bedded barrel. Though many styles (like Lancasters) generally use about a 50% flat coverage ratio, with others (like Lehighs) a 30%-40% ratio is more appropriate. If you cheat a little and decrease your coverage to 45% (if it's supposed to have 50%) nobody will really notice, and it will make the finished product look slimmer anyway--never a bad thing. Lessened barrel coverage will also widen out the angle of the V in the upper fore stock (if that's the shape you've chosen) to put you less at risk of breaking through. If you are still exposed on those cut out corners once the barrel is at full depth, it might not be a bad idea to glass bed it to get you some reinforcement in to that corner.

Not all styles use a V shaped fore end though. some use a flattened round one. If your chosen style compels that shape, you are less at risk of breaking through in to those corners. You will very likely need to put an end on your muzzle cap.

Keep us posted on your progress and what you do to address this. The sign of a good builder is their willingness to admit to their own mistakes, and address them. Everybody makes mistakes in their builds. The great builders just make fewer and smaller ones, and spend less time correcting them. Just remember, big tools taking off lots of wood at a time can make for big mistakes. In general, power tools are for making furniture, not long rifles.

 

[Larry (Omaha)]

Since you have squared off the barrel channel, Bill Raby is correct. A V-shaped fore end may not leave you enough wood for the integrity you need when you are shaping your fore end. The good news is that you probably have more web thickness than you actually NEED. That's a classic new builder mistake. Too thick of webs. If you are lowering the barrel in the barrel channel that will get you the wood you need to make a more proper 45 degree angle on the oblique flats for wood contact. Just don't lower it with more SQUARE inletting! Many slim (swamped barreled) guns actually get built with nearly ZERO web thickness at the breech, and 1/8" thickness at the muzzle. Your barrel lugs will probably break through to the RR channel, but that's not a big deal.

You can also help yourself by decreasing the barrel flat coverage with the fully bedded barrel. Though many styles (like Lancasters) generally use about a 50% flat coverage ratio, with others (like Lehighs) a 30%-40% ratio is more appropriate. If you cheat a little and decrease your coverage to 45% (if it's supposed to have 50%) nobody will really notice, and it will make the finished product look slimmer anyway--never a bad thing. Lessened barrel coverage will also widen out the angle of the V in the upper fore stock (if that's the shape you've chosen) to put you less at risk of breaking through. If you are still exposed on those cut out corners once the barrel is at full depth, it might not be a bad idea to glass bed it to get you some reinforcement in to that corner.

Not all styles use a V shaped fore end though. some use a flattened round one. If your chosen style compels that shape, you are less at risk of breaking through in to those corners. You will very likely need to put an end on your muzzle cap.

Keep us posted on your progress and what you do to address this. The sign of a good builder is their willingness to admit to their own mistakes, and address them. Everybody makes mistakes in their builds. The great builders just make fewer and smaller ones, and spend less time correcting them. Just remember, big tools taking off lots of wood at a time can make for big mistakes. In general, power tools are for making furniture, not long rifles.

Wow! Lots of good information! Please tell all this to my son in law. Also read my original post! I, Larry (Omaha) am not the builder!
Thank you for posting good information for others though.