brass or bronze liner

[holzwurm]

A while back I saw a gun heavily engraved and decorated. The builder had lined the pan with a sheet of gold and the touch hole also looked like gold but it was either brass or bronze. Which one would work?

Seems to me that brass would tarnish quickly but I don't know enough about bronze to make the call.

Anyone?

[BrownBear]

I look forward to the answers you get.  One of my hunting pards has an original 36 cal with a brass liner (yellow colored, anyway), and it's pretty well eroded or hogged out now from decades of picking.  He's still shooting it, but you definitely don't want to be standing very close when he lights it off.

[Long John]

The touch hole liner was probably ampco.  It is an alloy that looks yellowish in color and is quite corrosion resistant.  It is often used in lieu of stainless steel but is not as hard as stainless 302.

As for the pan, I'll defer to some one like Acer on lining pans with sundry metals.  Jerry Huddleston used to provide lot's of info on such topics but I haven't seen any posts from him in ages.  I hope he is OK.

Best Regards,

JMC

[holzwurm]

I think I have heard of that Ampco stuff. Yeah - I think maybe that's it.

[Acer Saccharum]

Brass is not very strong, in my opinion. Bronze is much stronger.
I used a stainless vent on my jaeger, and when I heat blued the barrel, the liner turned a nice brown. It is not a permanent color, but I think it would wear rather well.

[Scott Semmel]

Seem to think I saw a thread where it was implied that Brass brazing rod could be used to line a pan, kinda like tinning with solder. Your thread keeps bouncing from lined pan to vent liner. Hope the person who has the info can follow the thread, I'm  interested, seems it would be a nice touch if not too labor intensive.

[The other DWS]

If I remember correctly some high end guns had pans lined with gold an platinum.  gold would be a mite soft in terms of mechanical damage.  I don't know how well it would handle the blast and erosion in a vent liner.  I imagine that bronze would be used in preference to true brass.  at least it was in terms of artillery, true brass is too brittle.   However both gold and brass came in a number of job specific alloys which might have permitted such use.   I don't know when AMPCO was invented but I believe it is a relatively modern development.  if found on an old "original" it would be a fairly recent modification

[davec2]

The AMPCO bronzes have tensile strengths in the 100,000 psi ranges and yields not far behind.  As such, it is at least twice as strong as most mild steels, stainless steels, and most aluminum alloys.  I used to use a lot of beryllium copper, which is even stronger than the AMPCO bronzes and it will not tarnish.  (As an interesting side note, I used to alloy silver and beryllium to make a beryllium sterling silver alloy that had the very unusual property of never tarnishing and was much stronger than regular sterling but was still 92.5 % silver.)  Beryllium copper is not new - been around and used for more than 120 years - and we used to use it as a practice metal to simulate gold in the jewelry and dental trades.

[The other DWS]

Dave I've got a chunk of beryllium copper someone gave me years back.  I thought I'd grind it down for a knife guard, but I read or heard somewhere that Beryllium dust/grindings is real toxic so now it's just a paper weight in my shop.  that beryllium/silver allow sounds cool


Addendum}   FWIW I just googled Ampco,  http://www.ampcometal.com  its a swiss metal co founded in 1914 and they make a whole bunch of different exotic alloys  including a bronze aluminum and several flavors of manganese-bronze  which I expect is the stuff used in the touchhole liners

[davec2]

The Other DWS,

If you file or mill or saw beryllium copper, there is absolutely no issue with toxicity.  It is not metallic beryllium that is an issue, it is beryllium oxide.  Filling, milling, turning, sawing....none of these processes can generate beryllium oxide, but grinding, per se, can.  You can grind it safely, but the grinding should be done wet (i.e. with mist coolant spraying on the grinding wheel or sanding disk as the work is being done.)  They make a lot of non sparking tools for the explosives industry out of beryllium copper.

[The other DWS]

Cool!!l  thanks maybe I'll dig it out and do something with it.  I think it was a blank for making a large segmented bearing race

[D. Taylor Sapergia]

Before Chamber's White Lightning Liners were known to me, I used to buy Ampco beryllium liners from TOW in 1/4 x 28.  They served very well, and you have to be serious when you drill them out to change them.  I once drilled one out to accept an easy oujt that I made from the tang on a square file.  When I drove it into the hole, it peeled off four steel shavings from the steel.  It's very tough.

[smylee grouch]

I lined a pan with silver solder once, looked cool but didnt last too long. Just tinned the pan with silver solder when lock was unasembled so wasnt much work.   Gary

[The other DWS]

I just had a probably-strange idea.  Has anyone ever had a removable pan treated with the Armaloy or Meta-life process?  I had some Lyman iron mold-blocks treated with the Metaalife stuff a few years ago.  no rust worries and they drop bullets clean, practically of their own weight.  It'd give a nice silvery surface, rust proof,  easy to wipe clean, no gas cutting (I think)  kind of like a poor man's platinum lining?,  even better if they could only do it in the pan proper and the face that goes against the barrel flat

[Keb]

Ampco bronze (Aluminum bronze) is used on moving surfaces in dies in the auto industry for it's wear resistance. I use to make my own liners from Ampco bronze when I was still working. It is very tough stuff and works well for vent liners. As far as being historically correct, it is as correct as stainless steel. :/

[Acer Saccharum]

As far as being historically correct, it is as correct as stainless steel.

Yah, I think sometimes we get blindsided to some things which are out of context historically, but we use them anyway, be it for conveniece or performance. Goretex moccasin liners, stainless steel vents, sawed agate 'flints', rubber duckies, etc.

[bob243]

When looking at Ampco website, I see there are several series (grades?) of Ampco aluminum bronze,  which one would be correct for vent liners (or nipples)