You can save a lot of money by using HyloCool instead of the Brownells heat paste. I can't find it on their website, but my local Harbor Freight sells good sized bottles of it for like $5. We use it at my work but we get it directly from Hylomar. It's really amazing stuff, you wouldn't believe how well it absorbs heat.

OK just asking a question here, other than taking longer to heat up the solder, are there any other issues to using a propane torch? I am asking on the grounds that I already have a propane torch and I would prefer to use it if it isn't going to be extremely problematic. And if the only issue is that it will take longer, I can deal with that.

Still waiting on my barrel, so can't post personal experience yet.

Based on my experience soldering other stuff:

The paste is at least 50% flux. Probably more. So whatever volume of paste you apply, figure that only about 40% or so of that volume will remain after heat. The goal is not 100% solder coverage within the threads. Within the threads, gaps are going to occur, and they are okay. If there are 12 turns, and you get a good bond in 50% of 6 of the turns, a breaker bar will break the barrel before that weld will let go.

When the solder melts, it will wick into very tiny places, and it will always lay as flat as it can on clean surfaces. A super-thin layer that wicks into threads will lock the threads permanently.

When you start heating, the flux will melt right away. When you arrive at the necessary heat, the solder will melt. When it melts, it happens fast, and it sort of disappears into the joint. You'll see it happen, and you will know. Keep the heat on the joint for 3 seconds to push heat into the threads, and then make a slow circle around the barrel for another 5 seconds. That's it.

The reason for uniform heating of the joint (from the start of the job) is that once the solder melts in the hottest place, a slow circle of the torch around the barrel will chase the necessary heat level all the way around and ensure a good bond. When you pull the flame away, the heat loss is so fast that the joint will lock in less than 10 seconds.

You want enough paste "piled" up at the proximal edge of the joint so that a tiny solder weld is visible when you're done. Then an "inspector" can tell by looking that it's soldered on.

Plumbers use a propane torch to solder copper pipe. Works great. But the materials are thin-walled, highly conductive to heat, soft surface (easy to clean and prep), and nobody cares what they look like when the job is over, so heat migration doesn't matter. Yes - propane will eventually get you there. But you can buy a MAPP gas cannister for $10 and use the torch head from your propane bottle, and get there much quicker, which will mean less hassle fighting heat transfer during the job.

Your torch head needs to be the kind that makes a 6" long clean jet of blue flame; NOT the kind that makes a blue flame flower at the tip. The flower flame will never get you there. You can use torch heads interchangeably on propane or MAPP bottles. The hottest part of the flame is the tip, so bathe the work area with the tip of the flame, not the base of the flame.

Good question about a solder gob at the tip. The only way to get this would be way too much paste on the accessory. If you have too much, the muzzle will "bull-doze" paste in front of it as you thread the accessory on. To avoid this, use a light coat on the proximal half of the threads of the accessory. After paste-&-attach, but before heat, push a brush into both ends and "clean" the muzzle tip area a bit. If you have a gob, the brush will either drag it out, or smear it flat. Either way, it will be inconsequential. Melting solder wants to wick into a clean small crack or fall into a puddle in a low spot. IF you have excess material at the muzzle, and IF it melts (unlikely), and IF the gun is pointed slightly down, the material will fall to a low spot in the accessory, and later fall off. It won't run uphill into a huge open space like a barrel. But most likely, it won't even melt, because your heat threshold won't penetrate beyond the contact area of the threads.

Use a light coat on almost the entire thread section of the muzzle. The leftovers will get piled up at the washer as you thread the thing on. You can wipe some off if it looks like too much. If you don't get any material "piled" up at the washer, take off the accessory and add a slight amount of paste, then re-attach. You want about an 1/16" bead of paste piled up all the way around at the proximal end of the joint.

After cooling, test your job. If a wrench breaks it lose, go cleaner, use more paste, and try again.

But this is unlikely. Soldering is magically easy, and very effective. The hardest part of this job is controlling heat migration so you don't ugly up your gun.

I bought some HyloCool HERE.

I was planning on using rags and water, but what the heck.

O.K. so the B.A.T.F. approves the Silver Solder method. Great. Does anyone know if for any reason those of us in Corrupticut, sorry I mean Connecticut, an AWB state, that this might be an illegal method? Or do they just follow the same specs as the Feds?

Just curious. Lot's of great info here. As a DIY builder, I would love a way of not taking my guns to my local Smith (JoJo's I love you guy's sorry for this blasphemy) and be able to put on and off comps (no evil FH's for us) for our silly AWB on our regular length barrels. Once you commit to a FF tube system you are committed until that weld is ground off....
This would seem to be a MUCH better idea for a home builder to Silver Solder than blind pin weld. I too do not have a welder or drill press.

I've seen all the links for online, plus Brownell's, is this stuff available at a good Hardware store, like a really well stocked Ace Or True Value (represent Goody's East Haven, Family Owned!) or just the online places. I've also got access to a Harbor freight.

Or a mega Home can't find a worker for half an hour Depot?

I'd need the cooling paste, solder, flux, and torch. I'd appreciate opinions on best options as I'm starting from scratch, and yes I've read all the posts, but there is a multiple array of options, and I am totally new to this area of home-building and don't want Big Brother taking me away.....

Thanks in advance guys.

Do you have any Doit best hardwares around ?
http://doitbest.com/Solders+and+fluxes-Oatey+S+C+S-model-326098-doitbest-sku-326098.dib

[quote]Originally Posted By Drenman:
O.K. so the B.A.T.F. approves the Silver Solder method. Great. Does anyone know if for any reason those of us in Corrupticut, sorry I mean Connecticut, an AWB state, that this might be an illegal method? Or do they just follow the same specs as the Feds?

Just curious. Lot's of great info here. As a DIY builder, I would love a way of not taking my guns to my local Smith (JoJo's I love you guy's sorry for this blasphemy) and be able to put on and off comps (no evil FH's for us) for our silly AWB on our regular length barrels. Once you commit to a FF tube system you are committed until that weld is ground off....
This would seem to be a MUCH better idea for a home builder to Silver Solder than blind pin weld. I too do not have a welder or drill press. quote]

Good to go.

Why don't you use the low temp High Force 44 from Brownells. It needs only 475 deg F. No damage on the barrel.

Out of curiosity, why not the wire? I can't find any paste in my AO and need to put on a fh by Friday. Don't ask, I'm good at procrastinating...

If you get proper penetration of the weld you should not see the pin after it has been ground off. BATF would nail you on this!

PursuitSS

Ask a CERTIFIED welder if it is "welded" when you can clearly see the outline of the pin.

And is that legal hi-temp silver solder or just some low temp solder?

Well I dont know any CERTIFIED welders and ASAIK the ATF does not require any certification paperwork for the welding.

But here is a pic from one of the most popular places on this site to have the work done. I can see the pin

I'm not certified but for all I know that could be a set screw, JB welded, press fit, anything.

My point was how would they prove/disprove the welding if you cant tell by visual inspection.

I'd like to drill through the FH into the threads put a long set screw in one that extends out about 1", 1100deg. silver solder that in place by heating the screw not the barrel directly, then grind it flush.

this method would eliminate heating the actual barrel and discoloring a nice Noveske bead blast finish.

this would pass any wrench test, be easier to remove then the welded pin but harder then the 1100deg solder only. And easier to install then both

I know its not legit but I wish they would consider other options.

Thanks to this post, I finally got my 14.5 and Vortex mated together with the SS method. It discolored slightly where the heatstop paste started to dry up beyond the applied area on the flashhider. Slightly brown tinged, but nothing a little CLP couldn't blend up with existing finish. The adjacent areas beyond the heatstop got to about 240 at the hottest with the temp gun after removing flame from area to be soldered. Hope this wasn't too hot.