barrel cutting advice needed

[Dennis Glazener]

For what its worth. I used to build/shoot benchrest rifles and I (and others) were sure that a properly crowned barrel should be square to the bore, not the barrel. Even with precision made benchrest barrels very, very seldom did one have a perfectly straight hole through the barrel. I indicated the barrel in the lathe by running the indicator on a tight fitting "spud" in the bore, faced the barrel off square then cut the crown on the muzzle. Then I used a piloted 60 degree counter bore that fit the bore tightly to just true the crown with the bore.

I suspect muzzleloader bench guns are done in a similar manner.
Dennis   

[jerrywh]

 I agree with Dennis. There is no way to face a barrel or crown it correctly without a pilot in the bore for the tool. Any other method that turns out successfully is pure luck. 

[WKevinD]

Well I cut it, squared it, polished it and crowned it. I'll find out how well when I finish my project and go to sight it in.

All the advice has been accepted and digested and the balance between what is perfect and what is practical was keeping me from making a quick decision until I went out to the shop this AM   

I kept hearing two of my early mentors 
#1 "God hates a coward"
#2 "Bloody well, do it, you might bugger it up but then you'll have to learn how to fix it"

Kevin

[conquerordie]

I kept hearing two of my early mentors  
#1 "God hates a coward"
#2 "Bloody well, do it, you might bugger it up but then you'll have to learn how to fix it"

Kevin

Sage advice. I never would have done gunsmithing or anything really without it. I had a professional restorer tell me to by a quality flintlock and then destroy it. Then restore it. How else are you gonna learn!  Didn't go to that extent but there was truth in his advice.

Greg

[okieboy]

 I have squared and polished a muzzle to the bore with a simple homemade wooden tool. Drill a hole with your drill press through a piece of hard wood scrap about 2" square by 3/4" thick. The hole is the size of the biggest dowel that will fit into your bore. glue the dowel so that there is about 4" extending from each side. If the dowel is loose, enlarge the bore side with a wrap or two masking tape. Glue some sand paper (or use PSA backed sand paper) to the bore side of the hardwood. Put the tool in the bore and spin it a little. Remove and observe where the abrasive polished (just like stain transfer process). Lower the polished area with a smooth file and use the abrasive tool again. Repeat until the tool polishes the entire face evenly. Then crown the muzzle. I crown with a wooden radius tool loaded with lapping compound, but abrasive balls or sandpaper on your finger fill work.
 This simple method assures that the face is square to the bore. 

[James Wilson Everett]

Make an 18th c breech grinder, it will function just as well to crown the muzzle exactly square to the bore.  Here are some photos of breech grinders.







Last, cut a small chamfer at the muzzle end of the bore using an 18th c bore chamfer tool.  The tool is spherical so you don't need to be concerned much about alignment.  This just takes off the sharp edge, not for making a big chamfer cut.



Jim

[WKevinD]

That's amazing! The same solution to the same problem from two schools, if I had the tools to make the tools to do it I would use Mr Everetts solution but oikeboys solution is theoretically the same but with reachable tooling and resources and acceptable tolerances for my shop. Thanks guys this is going to smooth out another bump.
 

[Boompa]

  Now that 18th C rig I can get interested in.  Most of us do not have the means or the space for a $5k lathe to do the job.

[Dphariss]

I am about to start a project where I need to cut 8" off a straight tapered barrel. I know the muzzle is important to accuracy so I am looking for advice on cutting the muzzle square (hacksaw) and crowning the .54 cleanly.
I had thought about cutting the breech but have no tools or experience for a 3/4 x 16 thread.
Kevin

Cut the BREECH then rethread true and rethread for the breech. Unless you are 100% sure the bore in perfectly centered in the blank breech to muzzle. Some are not and if its "off"  8" back from the muzzle you are in trouble.

Dan

[Dphariss]

Harry Popes experiments showed that the angle of the muzzle changed where the bullets hit the target, but did not affect group size.

So hacksaw and file are fine, use a square to compare from opposite sides if your barrel is swamped.

Thank you. Its also interesting to note that the breech MLs he built had NO crown at all.
The BPCR shoots better with NO crown at all but I always put on just enough to break the lands just a little in case a patch had to be started from the muzzle for some reason. The crown on a brass suppository gun is to PROTECT the bore, nothing else.

Dan

[Dphariss]

The last time I checked my American history neither Twigg, or Manton had a shop on this side of the pond. This is about AMerican longrifles, right?

   Hungry Horse

Good grief.....
I really wish people would accept that the people in Colonial America were just as smart and capable as the people in Europe. The lathes of the time were not the 1700 pound versions like mine  nor were they barrel lathes, nor could you set up and make a .050 cut on a hardened steel part with a carbide tool. But a person could make round items like pilots and MOULD CHERRIES with them. A foot powered lathe and a file will be slow but a fairly round part can be made. Note at when a rifle was "freshed" or "cut out" to a larger caliber the MOULD had to be reworked as well. How did they make mould cherries? Or did they import them all from England? Even during the Revolution and War of 1812? Why was  the "long angle lathe file" invented and WHY?
Twiggs lathes.... Note that the MODERN lathe and milling machines did not appear until Kendall and Lawrence (probably mostly Kendall who was apparently a mechanical genius by things found in the Warner-Lowe  Papers) invented modern machine tools and tooling to fulfill a gov't contract for 10000 guns and a little later to make Sharps patent rifles and a host of other things. So the lathes in England in the 18th c were not what WE think of as lathes. I would also point out the REAL accuracy in rifles was not achieved until the advent of "modern" machine tools to do precision work.
I don't live in the 18th c., they could not even measure precisely. I am not limited to making things in the manner people did at the time. Given some of the things I have seen that have been made recently using the old ways I am happy. Example, barrels with off center bores will not shoot well no matter what the thing brings at auction.

Dan

[Tony Clark]

  Example, barrels with off center bores will not shoot well no matter what the thing brings at auction.

Dan

I'm just curious... what does an off center bore have to do with a barrels ability to group? What are sights for exactly? I'm confused at what you mean exactly.

[jerrywh]

 I want to refer people to the post I made in the back fence portion about the steam engine in the Colonies. How do you suppose they repaired that Engine or made it without some sort of a decent lathe. Not possible in my opinion.
http://americanlongrifles.org/forum/index.php?topic=38486.0

[rich pierce]

There are some logic flaws in many of these discussions.
If something existed in a country at a specific time, does it follow it was commonly available in small shops and was used there?  I believe this is the basis for several positions here.

Can anyone document that the gunshop at Christians Spring, or any gunshop with a single master gunsmith in say Lancaster County pre-1790 has a lathe capable and used to shorten or crown barrels?  There are lots of inventories of gunsmith shops.

The ball cherry argument does not hold because it is based on an assumption that one must have a lathe to machine a round ball. While it seems logical that would be true, it is not. A hole can be bored in a plate of iron to the desired size using a tapered reamer. The backside is countersunk to create a cutting edge. A slot is cut to the edge for shank clearance. This piece when case hardened will machine a rough forging to round.

Nobody here is advocating for sloppy shade tree mechanic work. But many are interested in exploring techniques actually in practice in many to most small colonial or Federal period gunsmith shops.

[James Wilson Everett]

Guys,

This topic has wandered a bit, but here is some info about cherries and how they were made.  This is a photo of two original cherries, one finished and one blank.  The blank cherry appears to be hand filed, it is not perfectly round (not hardly!), it shows clear file marks and no telltale circumferential marks from any type of rotating tool such as a lathe.  This is the only original unfinished cherry I have ever seen.  I think that a metal cutting lathe in an American 18th century gunsmith shop would be unusual to non-existent - my opinion.

Jim

[Boompa]

" I think that a metal cutting lathe in an American 18th century gunsmith shop would be unusual to non-existent - my opinion."  Mine as well.

[jerrywh]

Rich Pierce
  The method you described for making a cherry is exactly how I made my first cherry in 1960.
 I do not contend that lathes were common in 18th century American small gun shops.
I do think some shops probably had one but they were not common. Probably the ones who did made some tools for others like the breech grinders and muzzle facing tools.
 I have learned to never say never or never say always or everybody.  There is usually an exception to the rule.  What I contend is there were a lot of lathes in gunships in England and Europe. These were English colonies with a lot of gunsmiths from England and Germany. It is very logical to think that there were some lathes here. I fact some of the things made in the colonies would be impossible to make without a lathe like clocks. Do you think there were no lathes in Philadelphia?
 On web site of Colonial Williamsburg you will find a reference to a  metal lathe.
http://www.history.org/foundation/journal/winter08/tools.cfm
http://www.history.org/foundation/journal/winter03-04/foundry.cfm

[rich pierce]

Jerry, I agree 100%.

[James Wilson Everett]

Guys,

This is my opinion only.  Whenever I see a hand tool, that is a tool probably made my an individual smith, not purchased from Birmingham, that has clearly nice round sections (lathe made), I assume it is later 19th c or even 20th c.  Tools with forged, square sections are, I believe, of an earlier period.  To illustrate, this first photo shows tools with nicely made round sections and appear to be well machine made, obviously some type of metal cutting lathe - late 19th c or early 20th c.  I know that these were used by the Fry brothers in Ligonier, Pa. in this time period.



Looking at these tools, we can see no evidence at all of any type of lathe tool.  These appear to be of a much earlier period, 18th c.



Jim