You need a temperature range of 1200 to 1400 degrees Fahrenheit, depending on the chemical composition of the joint, to melt silver brazing material. A normal propane torch can reach 3600 degrees open air temperature but can't sustain those temperatures under normal use without a proper work environment and/or the addition of oxygen to increase the burn temperature. Thats where the torch comes in as Luke mentioned. You can also purchase high temp bottles that have a higher oxygen content such as the BernzOmatic Oxy / MAP-Pro™ that has a 5700 degree open air temp. You should be able to maintain your requried 1400 degree metal temp with that flame.
The welding of the feed tubes on the body was done by silver solder. I don't know why people call it silver solder. It should be called brazing, not solder. Soldering is only for low temperature metals that melt below 840 degrees Fahrenheit. Brazing is for high temperature metals above 840 degrees.
Except for the Automag in front, its usually the man behind the equipment that counts.