View Full Version : GasTube: Parkerizing Brazing Soldering Heat

November 14, 2000, 06:19
Two questions:
1. Does heating with a MAPP gas torch such as when attaching a MB affect parkerizing, does it damage or degrade it?

2. The amazing repeating gas tube questions!!! I think the gas block on one of my R1 kits is worn out. The gas tube fits loosely even when tightened and particularly when in the "pinned" position. Tube looks good... (I have a few, chose the best). Is it practical to just silver-braze the tube in place and cut off the end like an Austrian STG? Also the gas plug seems loose too. Should I replace the plug, gas block or just not worry about it? Not building a trophy, just a shooter. Thanks, RT

[ July 22, 2001: Message edited by: gary.jeter ]

November 14, 2000, 11:12
I heated mine to almost red hot. No major adverse effect on the park job. Your mileage may vary.

The shorty gas tube is probably a good idea for troops who would neglect the long tube to the point where oozing primordial life forms eventually cause a malfunction. From a mechanical standpoint, there is no need for a long tube. I prefer the long tube for the very reason that motivated your post. I don't like the gas tube wobbling all over the place.

The next time I try to solder or braze a gas tube, it will be a long one. I'll do it with the barrel on the receiver, and the tube secured secured at the rear in the gas-tube fastening nut (collar) to increase my chances of getting proper alignment.

If you do go the route of soldering, you should use nothing less than high-temp silver solder. You want the stuff that melts at over 1000 degrees. You do realize how hot the gas block gets during a 100-round string. Unless you are soldering wizard, the silver-solder paste is the only way to reasonably assure that the solder reaches the whole joint.

[ July 22, 2001: Message edited by: gary.jeter ]

November 14, 2000, 13:30
Actually I had intended to use Brownells silver solder paste. You just smear it in the joint, heat and your done. I planned on doing the work with the long tube in place, complete with gas tube fastening nut and shims to hold the tube dead center. When it's done a cutoff wheel on a die grinder would shorten the tube nicely. Deburr and your done. I am debating replacing the gas block as it is corroded and the gas plug fits loosely. We'll see how ambitious I get. Thanks for the ideas though. RT