Barrel inlet tolerance

[coopersdad]

I've finally completed inletting my first swamped barrel.  I got a bit too aggressive with a scraper in a spot about 12" long near the waist on the side flat area, and I can see a gap and can run a .005 feeler gauge in there.  If I push the barrel from the opposite side, I can slightly flex the barrel over to close the gap.  I'm thinking this would be too much gap when the forestock is brought to 3/32" or so - wood would be weak/unsupported there?   My solution would be to glue a thin strip in there and re-fit it in that spot (early Lancaster with a C wt. barrel).   Am I thinking right or being too critical? 

[David Rase]

Is it really .005" or .050".   .005" is nothing.  Wood swells and shrinks that much.  I only ask this because you mention gluing in a thin strip of wood and .005" is definitely thin.
DMR

[rich pierce]

Soak the heck out of it; wet it and then stuff a wet rag in there.  Put the barrel in with a saran wrap covering.  Clamp it and leave overnight. 

If that doesn't work, consider the glue job but glue alone will be a couple thousandths sometimes.  Set your best low angle plane to take a very light cut, get a nice curl off the blank somewhere, and flatten it with a steam iron. Cut to shape with a sharp pair of scissors while still damp, apply white glue to both surfaces, and clamp the barrel in place, wedging the patch in there.

[coopersdad]

It's .005 - it's thin.  I'll try the soaking trick.   If I glued a strip I'd probably have to take a bit more off and use a thicker strip, since as mentioned, I might get into the glue when I scrape it back down.  Likely I'm getting my nose way too close to it and it looks like a huge chasm from that close...  Thanks!

[Randall Steffy]

A typical business card is 0.010" thick. Half that thickness in clearance and I would personally call that a snug fit. Your finish will make a beautiful to tight fit if you ask me. Good job!

[bgf]

0.005"!  "Gaping chasm", indeed.  I was sure it was a mistake and maybe 0.05" like someone else said.  I don't know what the right thing to do is, but I would leave it alone or scrape out the rest to match .  Finish or sealer in the channel will eliminate some of that, and the wood will probably swell up at times, also, as others have mentioned.  I would be afraid that a "perfect fit" (never had to worry that much about the possibility, to be honest) would put too much stress on the fore end when removing barrel.  Also, I'm not sure I get the part about flexing the barrel -- a c-weight isn't hefty, but I'm surprised it will flex that way (it wouldn't surprise me on an a or b weight) -- are you sure it isn't the wood moving?

[Simon]

Some  my worst mistakes don,t look so bad after a day or two, and mine are a lot larger than .005.  Leave it alone for a while then decide if you need to do any thing to it.  I will bet not.

[Dphariss]

.005 is not enough to worry about. Sealing the barrel channel with finish will fix it. In fact raising the grain in the barrel channel may fix it.

Dan

[Jay Close]

A very large percentage of the old barrel inlets I've seen on American longrifles are scooped out, half round channels with just the breech area and perhaps the muzzle area made to fit the octagon of the barrel. This wasn't London quality work, but the barrel receives essentially no support from the thin sleeve of wood around it any way, particularly way out there toward the muzzle. I'd say relax. I would worry about getting a very good fit at the breech and used to fuss there a lot.

[Mark Elliott]

I would say that .005" is a good inletting job.   Those gaps will close up, either actually or visually, by the time you finish the gun.   As you cut away the wood around the barrel,  it will tend to warp toward the barrel closing up those little gaps.   Also, the wiskering and AQ application will tend to close up those gaps.    The important thing is to may sure the gap is uniform along the barrel.   Those will close up and disappear.   It is the little digs that won't disappear.   Even a tiny ding from a stray chisel or file will stand out like a sore thumb if the fit around it is uniform and tight.    I feel that it is best to smooth our the sidewall of the barrel channel with a square rasp even if it opens up the gap a little more.   As long as the gap is even, it won't be noticed so much.   

If you have an even, noticeable, gap, you can close it up some by soaking he INSIDE ONLY, of the barrel channel with water, replacing the barrel and letting it dry.    It will at first push the sidewalls out, but when it dries, it will dry tighter.

It is best to leave all this to the end.   Wood moves all over the place.  Before you finish the gun, it will bend, twist, swell, and shrink.   Over the course of a year it is normal for a stock to swell and shrink 1/16" laterally and 1/8" longitudinally.   You are not cutting plastic or metal that only responds to temperature.   Wood can be a real pain to inlet because of this.   I keep track of the humidity in my shop and will not do any inletting when the humidity is really high, like over 70%; definitely no inletting during a thunderstorm.    Around here the humidity can change 30%-40% in a matter of minutes when a summer thunderstorm rolls through.    I was inletting a barrel once when one of these rolled through and the barrel was in the stock.   I thought that I had accidentally super glued it in.   I could not remove that barrel no matter how hard I tried.  It just wouldn't budge.   I had to wait for the humidity to drop a bit to get the barrel out.