Dealing with barrel seams, metal barrel?

Okay so this is only my second attempt at metal barrels. The first was a flak 38 and the flash hider went over the barrel for a nice fit. This one is a 17 pounder with a two piece muzzle break. Where the two muzzle break halves come together I have a very fine seam. It’s barely noticeable and can only feel it when I flick a finger nail over it. However I feel primer will make it very obvious. I’m wondering if anyone else has had this crop up and how you deal with it?

I thought about super glue but worry ill make a mess of it. I tried putty but I can still feel the gap


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I usually use two part putty (Magic Sculpt). I wait until it is just hardening, then wipe with a wet cloth wrapped around a small metal ruler. That generally reomes excess without pulling putty out of the join.

I have also used solder in the past. It is soft enough that you can sand away any excess without damaging the brass if careful

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From my supplies, I would apply Mr. Surfacer 500 or 1000 and let it dry, then clean it up with a Q - Tip moistened (not wet) with lacquer thinner.

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That’s what I tried so far but it didn’t fully do the trick. It’s possible it didn’t dry enough and the q-tip was too wet, it ended up pulling som of the surfacer out of the joint

That’s what I would say, that the Q - Tip was too wet and pulled too much of the Mr. Surfacer. Try it again.

Will do! I’ll try the 1500 this time too as it flows a bit better into small joins

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When working with metal joints, solder is always the best way to go. Tin one half with a very thin layer of solder. If it goes on too thick you can sand it off to thin it out. Put the two pieces on a wood dowel, toothpick, or something else that won’t melt or be joined with the parts via the solder. Bring them into contact and heat the joint from the outside until you see the ring of molten solder around the rim. You can then chuck it up in a Dremel and carefully bring the edge into line.

Any tips on controlling how much solder gets in a joint? I tried soldering some PE earlier on this kit and made a bit of a mess with too much solder. I was able to fix it with careful filing but it took a while!

I’m fairly new too soldering so any tips would be appreciated

The best way is to use very fine solder wire. I use .5mm stuff (which also great for scratch built piping) and the snip off a tiny piece that I place on the part. APPLY THE HEAT TO THE OPPOSITE SIDE OF THE JOINT, so the solder flows to the heat across the joint and not directly to the iron. You can also buy TIX solder and their liquid flux. It’s a lower melting point solder. I use that flux on brass even when I’m using rosin core solder. DON’T USE THEIR FLUX ON ELECTRONICS. It is corrosive.

Sounds like it’s time to order some thin solder! Thanks, I wasn’t aware it came that fine so I’ll take a look for it

Here’s what you should order from Amazon

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Thanks! Appreciate it