I FIANLLY HAVE A WORKING COMPUTER AGAIN! Someone had mentioned my name ...
I'm going to throw my $0.02 in here, but with the caveat that my copy of Bird, Stewart and Lightfoor is at my other office (in case you wonder, I hold a Master's degree with Highest Honors and transport phenomena was one of my stronger subjects. My thesis involved particle settlement)
On the use of small threads. While I appreciate the concern from the barrel supplier (I had to sign that waiver Bill mentioned), I wonder why well-respected industry names like Vais, AWC and others do not seem to have the same reservation on thread v. bore. I speak toward the .45 caliber bores here, but AWC is all too happy to put 9/16x24 thread on a 45 ACP barrel for a muzzle mount can ..... Similarly, Colt will gladly thread a 9mm (.35 cal) barrel with 1/2 x 32 threads. Perhaps the barrel supplier is overly cautious?
On the use of "glue". Rather than argue the pros and cons, how about we work together to get BATFE to accept Rocksett as a permanent installation? Like Tony said, taking it off and sticking it on can be a great way to pass the time while waiting for paint to cure or pizza to arrive. But having the option would be nice.
On rocket engines. Looking at most FLASH HIDERS I have seen, I see the typical divergent section. Most all lack the convergent section, using a sharp entry angle. This does NOTHING to aide in the fuction of the nozzle, as the intent with nozzles (in the application I use them) is to limit the distance the vena contracta is located from the nozzle to limit power loss. Power loss is bad in my daily life as it wastes energy and costs money. For flash hiders, the theory I have seen postulated is that of rapid slowing and cooling of the muzzle gas to quench any combustion. From my perspective, I am not sure I agree and Ron Silvers photographi, IMHO, appears to support another theory. Cool thing is, I can actually build a flash hider to test my theory. I base this opinion on using VERY similar items in industrial settings on a daily basis.
Now, to brakes. First challenge for Shivan's request is that to reduce muzzle rise, it would mean an asymmetrical design. That presents a challenge in both machining and installlation but not insurmountable. As to the designs out there, I could try and discuss the workings, but why should I if Lutz Moeller does such an excellent job on his website (along with high speed shadow photography of brakes in action). Seems some guy named Newton put together some rules that just can't be broken .....
Well, not sure if I helped at all with my ramblings, but it feels good to be back to ARFCOM. Now if I could resurrect my EMail that would be nice.