barrel stamps

[David R. Pennington]

A lot of the old barrels have proof marks and makers stamps. I recently got around to finally making a punch with my touch mark on it. Is there any possibility of damaging a barrel by punching marks on it?

[Bob Roller]

It might be damaged if it's very soft steel and thin walled.

Bob Roller

[Dr. Tim-Boone]

All I can tell you is I think wrought iron barrels must have been softer than 12l14 cause I practiced and practiced on a test barrel and never could get a decent signature from the proff stamp I bought from TOW.......

[Acer Saccharum]

You may turn a close-fitting rod, and insert it in the breech.

A technique for stamping goes like this:

Start the stamp on one edge, with a light blow.

Re-set the stamp in the depression, lining it up as best you can. Hit it again to deepen it.

Once you start getting a good impression on one edge, start tipping the stamp more upright, by degrees, and keep stamping it deeper. Eventually, the stamp will be vertical, and you will have a good impression.

Never, ever, try to whop it in there with one huge hit.

[Don Getz]

Acer.........what, no big swat with a 4# sledge?  That's how I do it with the letter "G" when someone want it.  We do clamp
the barrel onto a magnetic chuck which dampens any vibration........Don

[James Rogers]

That is exactly how I used to do it before I fitted out an arbor press to stamp with.

You may turn a close-fitting rod, and insert it in the breech.

A technique for stamping goes like this:

Start the stamp on one edge, with a light blow.

Re-set the stamp in the depression, lining it up as best you can. Hit it again to deepen it.

Once you start getting a good impression on one edge, start tipping the stamp more upright, by degrees, and keep stamping it deeper. Eventually, the stamp will be vertical, and you will have a good impression.

Never, ever, try to whop it in there with one huge hit.

[Dave B]

Ron Scott told me about a situation with a hydraulic press that punched the stamp right through a section of barrel. I think they were literally only using a smallsection of barrel scrap for testing out the different ways to sink the touch mark

[Mark Elliott]

Acer.........what, no big swat with a 4# sledge?  That's how I do it with the letter "G" when someone want it.  We do clamp
the barrel onto a magnetic chuck which dampens any vibration........Don

You are just tickling the metal with that.     A 4 lb cross pien is my favorite blacksmithing hammer.    I use a star punch for decoration, but I don't have a big enough hammer to make a decent mark in cold steel or iron with the stamp that makes my initials in raised letters.   I think that is what the rest of you are talking about.   I think that I would only use that stamp on gold or silver I inlaid in the barrel.  I do use it to mark my leather work.   Even at that, I have to hit it several times to make a decent impression.   

[David R. Pennington]

The punch I made makes a good mark on hot iron but I haven't tried it on cold steel yet.

[davec2]

This is a re-post of mine from a few years ago:  Original post and discussions here:    http://americanlongrifles.org/forum/index.php?topic=1138.0

I finally had a chance to take some pictures of the hydraulic press I mentioned in your post about stamping.  This first picture is of the entire press.  It is a simple welded assembly of 2 inch square tubing.  A hydraulic jack, with a pressure gage that reads cylinder pressure, just sits on the bottom plate and pushed against the bottom of the lower, movable platten.  The lower platten has two shoulder bolts 180 degrees apart that ride in slots milled in the vertical members.  Inside the verticals, tension springs are attached to the shoulder bolts and to bolts running through the lower end of the vertical pillars.  These springs will lower the platten when the bypass valve on the jack is opened.  The upper platten is fixed to the upper horizontal frame members and has a 3/4 inch hole in the center.  The center hole will accomodate different tool holders and / or anvils.  I use the press to stamp, coin, bend tangs, bend barrels, punch out sheet, press powder, etc.  Very handy tool.



Stamps, tool holders, anvils, etc.



Close up of stamp in holder.



Stamp being used to mark a scrap piece of barrel.



In this particular case, 2000 psi is being applied to the press (this is the cylinder pressure but the cylinder has a cross sectional area of about 1.75 square inches which means that the applied force is about 3500 pounds.)

This is the resulting stamp impression.  Very even and very repeatable with the pressure gage.



Graphite EDM tool to make coining (makers mark) stamps.



Some of my makers mark stamps.



Result of quick and dirty test pressing (really coining) of 24K gold, 0.025 inch thick in a recess quickly cut by hand graver in barrel steel.  Pressed at 3200 psi hydraulic pressure - no distortion of the interior of the barrel (.45 cal, 13/ 16 across flats, no interior support)



The following is another press I used to use for making black powder.  I now use this new one with a different set of tools to press 4 inch diameter "pucks" of powder prior to corning.

[RAT]

Matt at North Star West uses a press. He told me it took several learning attempts to get a decent impression without deforming the bore.

[davec2]

Although I use the press for a lot of marking, I also use a hammer.  Here are a couple of places, on curved surfaces, that require using a hammer.  This is a large stamp…about 5/16" tall, so I use the rocking method that Acer describes with several light hammer blows.

[Acer Saccharum]

Some early work may have been stamped when the iron was still hot.

I can't imagine a stamping this deep would not have affected the bore.

[Cory Joe Stewart]

I am working on a Clay Smith kit.  It has a couple of deep and very crisp stamps.  He may be able to provide information on this.

Coryjoe

[mattdog]

The amount of horse power needed to set a stamp is directly related to the square footage - or in this case square centimeter area of the stamp.  Simple letters can be set easily with a 1 or 2 lb. hammer.  For proof stamps and my sitting fox in a circle stamp etc. I use a 3,000 lb. capable flywheel drive punch press.  It is very quick.  ker klunk and it's done.  I might punch 20 lock plates at a rip so I need something fast and accurate.

Punching barrels is different.  I do them one at a time as needed for a specific gun.  I found out the hard way that it is possible to hit it too hard, punch through and create a bump inside the bore  !!    

[Dphariss]

It is amazing what can be felt or seen in a rifle barrel.
Most dovetails in a rifle that has been used much can be felt especially on light weight barrels even fairly tough stuff like 1137.
When I worked at Shiloh Wolf was roll stamping barrels one day with the little machine they used for that.
Suddenly their was an outburst of language from that area. Wolf had switched from standard weight barrels to #1 heavy but forgot to rest the machine. Standard is about 1" at the breech, #1 about 1 1/8". It was possible to look through the bore and see where the stamping was on the outside of the barrel.

Dan