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Discussion Starter · #1 ·
I'm so angry with myself. I have a CA-94. SBR'd it, everything was going well. I needed to get the faux suppressor off.
What a pain!
I ground down the weld, tried tapping it off, etc. No luck. I took everything very slow and was very cautious.

I ended up having to cut down the fake suppressor lengthwise to split it a bit and loosen it. It was working, but not enough. I cut some more, etc.
I finally got it off, but saw that I had somehow cut into the end (not the tip, but past the lugs) about 1/32" or 1/24" or so. The worst part is that it definately did not look like I was doing it!:mad:

I feel like an idiot. I don't really feel comfortable with the idea of shooting through this barrel. However, I don't feel confident in my ability to install a new barrel (don't even know how, and judging by my performance in this little venture, I don't trust myself).

So, which place seems to have the cheapest barrels?. I know Gordon Miller is selling Urbach MP5 9mm 3-lug barrels for $425.
I also need it installed and headspaced. There are no qualified HK smiths around where I live (central GA). Where can I get this done? Does Gordon Miller install them?

Keep in mind this IS a Class III weapon.

Thanks, and try not to rag on me too much
 

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Man, that sucks. That sounds like an expensive mistake unfortunatly. I had Ralph at RDTS install a new barrel in an HK SP89, and he did a great job with fast turn around. Good luck.
 

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I'm so angry with myself. I have a CA-94. SBR'd it, everything was going well. I needed to get the faux suppressor off.
What a pain!
I ground down the weld, tried tapping it off, etc. No luck. I took everything very slow and was very cautious.

I ended up having to cut down the fake suppressor lengthwise to split it a bit and loosen it. It was working, but not enough. I cut some more, etc.
I finally got it off, but saw that I had somehow cut into the end (not the tip, but past the lugs) about 1/32" or 1/24" or so. The worst part is that it definately did not look like I was doing it!:mad:

I feel like an idiot. I don't really feel comfortable with the idea of shooting through this barrel. However, I don't feel confident in my ability to install a new barrel (don't even know how, and judging by my performance in this little venture, I don't trust myself).

So, which place seems to have the cheapest barrels?. I know Gordon Miller is selling Urbach MP5 9mm 3-lug barrels for $425.
I also need it installed and headspaced. There are no qualified HK smiths around where I live (central GA). Where can I get this done? Does Gordon Miller install them?

Keep in mind this IS a Class III weapon.

Thanks, and try not to rag on me too much
You could get a real MP5 barrel from Adam Webber @ www.hkparts.net for $375, or a threaded MP5-N barrel from same place for $475. I'd go with the real MP5 barrel, you'll save a little bit, and it's an authentic German HK barrel. But the Urbach barrels are great, and brand new.

How far past the lugs were you? If you were way out near the end, just have it cut off. A local gunsmith or machinist would be able to do it with no problems. Also, how deep did you go? Remember, a lot of barrels (like the MP5SD) have holes that go completely through them. Have a gunsmith look at it, you may be able to have it tig welded up, then sanded back down, or might even be able to just leave it like it is.

But if you do want or need to have it replaced, you probably won't be doing it yourself. First you need to pound out the roll-pin that goes through the trunnion. Then you'll need a press (I think a 12 ton one will work) to push the old barrel out. Then, if the new barrel comes with the triple-frame on it, you press it back in from the outside. However, the "correct" way to do it is to remove the triple-frame, rotate the barrel 120 degrees so that the lugs are aligned properly and you have fresh material that is aligned with the trunnion cross hole. Then press the barrel back from the inside until you get the proper bolt head gap, then drill a new cross-hole and pound in a new roll pin. Then weld the triple frame back in place. At the minimum, you'll need a press. To really do it right, you'll need a press, a mill (or perhaps could get by with a drill press), and a tig welder. Then you'll want to have it refinished, but could get away with spot refinishing where the sight frame was welded back on.

And no, Gordon Miller doesn't do it himself. Urbach does most if not all of his work which is probably why my friggin' G3K has been there since April. Which reminds me to go by and check on it again in a few days.

If it were mine, I'd send some quality high-res pictures to IFG, RDTS, or maybe TSCMachine and get their opinion. They will be able to tell you for sure what you can do.
 

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if you didn't cut too deep into the barrel, then I would not worry about it, as long as you didn't go all the way through into the bore

like AV Dave stated you probably can have that cut tig welded over and smoothed out. The front sight on those HKs are pinned onto the barrel, just like AKs, which means that they had to had to notch out a good chunk of the barrel to place the pin it, and that doesn't effect the performance of the barrel.
 

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Could you take a photo of the actual spot you are talking about?
That would help the board come up with a more accurate diagnosis.
TC
 

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if you didn't cut too deep into the barrel, then I would not worry about it, as long as you didn't go all the way through into the bore

like AV Dave stated you probably can have that cut tig welded over and smoothed out. The front sight on those HKs are pinned onto the barrel, just like AKs, which means that they had to had to notch out a good chunk of the barrel to place the pin it, and that doesn't effect the performance of the barrel.
The clones just pin the triple frame to the barrel? Hmmm. I wonder why they didn't just weld them on with those hideous welds like on the rest of the gun. :)
 

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Could you snap a pic of where the cut is to also give us an idea of how deep it is? Depending upon the depth/location, you could send it to Jayson and he might could thread the end of the barrel and put the knurled thread protector on it to hide the cut altogether.
 

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Sorry you had such a tough time with the fake suppressor Kap.

I will be in the same boat once I get my Form 1 back.

I am really surprised that nobody has done a pictorial "how to"
thread on the proper way to get the fake cans off yourself without
damaging the barrel.
 

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If it is at the end of that barrel and not too deep you could get the barrel threaded like a MP5-N 1/2 x 28 pitch

Just an idea, that should be cheaper than a new barrel and install.
 

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If it is at the end of that barrel and not too deep you could get the barrel threaded like a MP5-N 1/2 x 28 pitch

Just an idea, that should be cheaper than a new barrel and install.
I thought of that today - not from the standpoint that he could repair it by threading it (although that is a good idea), but from the standpoint that it can be completely left alone and won't cause any problems.

There is a lot more metal removed when the end is cut down for threading than he probably cut into it with the hack saw, unless he really cut deeply into it.

Odds are it's just a cosmetic defect at this point. If it bothers you, fill it with JB weld and paint over it. You'll be the only one that knows.
 

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Discussion Starter · #12 ·
I actually thought of the JB weld idea earlier. I ended up spraying over the end of the barrel, since the faux suppressor removal had stripped the paint, and it makes the crack much more noticeable.
Would JB Weld hold up to the heat?

I'm working on pictures
 

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I'd just cover it with a flash supressor if it's not functionally impacting the firing of the bullet.
 

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I was told that the pin holding the fake can/barrel extension on is actually soldered into place and tack-welded over top. Once you grind the weld flush, you needed to hit it with a torch to warm it up until the solder flowed. The pin should have just come out at that point (still hot).

Sorry to hear about the mishap, pics of the severity of the damage would help with everyone's assement, but I think you've heard all of it already.
 

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Most gunsmiths are comfortable with barrel walls as thin as .125", and that's with rifle caliber rounds. If the aesthetics don't bother you, hit it with some flat black paint to keep the rust at bay and as others have suggested put a 3-lug FH over it. Or get it threaded. Or replace the barrel entirely.
 

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I actually thought of the JB weld idea earlier. I ended up spraying over the end of the barrel, since the faux suppressor removal had stripped the paint, and it makes the crack much more noticeable.
Would JB Weld hold up to the heat?

I'm working on pictures
Absolutely. It can withstand constant temps of 500F, and 600F for up to 10 minutes. Could you get it that hot with sustained full-auto firing? Probably. But those temperatures are tempering temps for some tool steels, so if you get the barrel that hot you'll have other problems, some of which are the plastic forearms melting off, the paint blistering, etc.
 

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Discussion Starter · #17 ·
Thanks for all your input. I hit it with some flat black high-heat paint today. It doesn't match the color of the rest of the gun, but I don't mind--as long as it's not silver. It definately makes the cut (actually two, but the other one is more of a mark) very noticable. I do intend to put a flash hider over it, but the JB weld news is great. The rifle is semi only, and the plastic furniture didn't even occur to me.

I'll strip the paint, fill in the cut with JB weld, repaint, and install a flash hider over top.
Thanks again
 

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Discussion Starter · #18 ·
I was told that the pin holding the fake can/barrel extension on is actually soldered into place and tack-welded over top. Once you grind the weld flush, you needed to hit it with a torch to warm it up until the solder flowed. The pin should have just come out at that point (still hot).

Sorry to hear about the mishap, pics of the severity of the damage would help with everyone's assement, but I think you've heard all of it already.
I don't have a torch, but I really should've borrowed one. I did free the suppressor from the pin itself, and it was still a HUGE pain to get off. Hence why I actually resorted to cutting it lengthwise to pry it apart. I have a mallet and tried thumping it off, but I have no clue how one is supposed to be able to do that. I used everything I could think of as a sort of "punch" between the mallet and the fake suppressor to remove it (including punches) to no avail. This thing was the biggest pain to remove.

I HIGHLY recommend, if you're going the mp5 SBR route to go with a pistol if possible. I'm 20 so this was not an option for me.
 

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Reply from Vector

I got this official response from Vector when it comes to removing the fake can:

"Removing the fake suppressor can be tricky. It is pressed on and then pinned. You can find the pin by looking around the back of the suppressor and finding the spot where we welded. It will be a bump. You then file or grind the bump off until you can see the outside profile of the 1/8" pin. The suppressor is aluminum and the pin is steel. When you see the pin, tap the opposite side of the suppressor and try to make the pin fall out. If is doesn't, you might have to drill down the side of the pin until you can get ahold of it or dig it out. It is anchored into one of the trilugs. That is the easy part. Because the suppressor is pressed on, usually it will not come off by just pulling on it. You will have to come out in front of the front sight tower about 1 3/4" and cut the suppressor off. This should miss the barrel. Then you will have to see where the trilugs are and aren't so you can split the suppressor piece down between two of the lugs. From what I have seen, people use a dremmel tools with a little cut off wheel on it. Be observant here because you down want to cut into the barrel. There is 1/8" space between the suppressor and the barrel so you can miss the barrel when cutting as long as you are between the lugs. If you cut all the way through the suppressor piece, you can insert a flat-blade screwdriver and pry it open a little and the piece should slide off"
 
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