Shotgunlover: on the lugs brazing wouldn't be as big of a problem, but to get the barrels hot enough to mount sights or ribs would be too hot and likely to cause warping and ruin the barrels, which is why lower temp solder is used. From my understanding the difference between solder and braze is a temp thing with solder usually(but not always) the lower temps.

Yeah I abandoned that idea, I decided to go the longer but more rigid route for the monoblock.