Daryl I don't have the temperatures memorized but brazing is done at several hundred degrees F higher than soldering. Soldering can be done with lead/tin or silver/lead/tin mixtures.
The high grade English guns were silver soldered. To regulate them they would shoot them, stick hot irons in the barrel muzzle to soften the solder, adjust (move) the barrels, let them cool, and shoot them again. They would repeat this until both barrels had the same point of impact. Because of the solder the barrels must be rust blued, not hot blued. Because they used a solder with silver content they had to solder at a higher temperature but not anywhere near as hot as required to braze.
AYA, even on a Number 1 grade, brazes their barrels. Any regulating that is done is done by shaping the internals of the barrel, not by heating and moving the ends of the barrels. They can be and are hot blued. Now to make the brazing easier they may use a rod with up to 15% silver in it but it is still brazing.
Best,
Mike
Edit - Added the information below:
The rod we use to braze copper piping for refrigeration and med gas systems melts at 1310 degreesF and may contain silver. Typically 93% copper and 7% phosphorous
To braze steel to steel the rod would probably melt at 1145 degreesF. Probably a copper and tin mix.
50%/50% lead/tin solder melts at 361 degreesF
94%/6% tin/silver solder melts at 431 degreesF
Best,
Mike
Last edited by AmarilloMike; 01/20/09 08:40 PM.
