I do pretty much the same thing for minor inletting or checkering boo-boos. I make it up with shellac flakes, wax, and spirit stain. Your idea is way easier. Also use it behind the tang where it’s helpful to leave 0.020” to prevent splitting. I hate splitting;-). Also use it for filling gouges in furniture.Not a huge fan of doing a full bending on a muzzle loader. If the intention is to free float the barrel that’s going to take a lot of arca glass and some skilled work with resins and release agents.
On my guns I use arca for repairs, and gaps if needed, but i haven’t used it in years. The last time I used it was on a Miroku charleville (which I’m restocking now) because stock had broken a few times at the rammrod entry area. For me it was always a last option to use arca glass.
I prefer a more organic method and use caranuba wax mixed with mohawk wood filler wax, I melt Them into a tin and brush on to the stock while its hot, let dry and I use a cotton mop bit to shape it out. The Carnuba wax leaves a hard almost glass like shell but is much easier to remove or scrape out. While it wont add much strength to the channel it helps keep it tightly fit.
Now if you took out too much in the barrel channel and you have some large gaps as you had mentioned, i suppose arca glass can fix that problem or you can shim the barrel channel with veneer wood.View attachment 107372
That’s an interesting formula, I’ll have to give it a try.I do pretty much the same thing for minor inletting or checkering boo-boos. I make it up with shellac flakes, wax, and spirit stain. Your idea is way easier. Also use it behind the tang where it’s helpful to leave 0.020” to prevent splitting. I hate splitting;-). Also use it for filling gouges in furniture.
NMLRA regulations make no mention of bedding procedures.If you want to shoot in National or International competitions you will find that glass bedding is a complete no-no .natural products like wood glued in with a natural glue are permitted . I believe the old time makers weren't too concerned about accurately bedding octagonal barrels . I bedded a Pedersoli Tryon with a compound made from charcoal dust and pine resin heated and mixed . It worked perfectly , that was 30 years ago and I believe it is still going . I bedded the face between the patent breach and the tang , with the bedding on the tang , and that made a major improvement to accuracy .