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Discussion Starter #1 (Edited)
When I purchased my Scar 17s way back I had to have some things done to it to make it compliant in my state. One of those things was getting the muzzle brake pinned and bind welded.

Fast Forward..............

Now the compliant regulation is no longer an issue (legit reasons that I don't want to babble about now). So, I decided to send my 17s barrel to Adco to have the brake removed safely. The service was good, got the barrel back and it looked great. I happily mounted my AAC Blackout F.H. on it.

Fast Forward a little..........

AAC comes out with the Brakeout 2.0 and I'm like damn it! Now I ordered my Brackeout 2.0 and it's on the way. Then I am faced with the task of removing my Rocksetted AAC Blackout F.H. So tonight I got ambitious and removed it. Things went beautifully and I got the Blackout off nicely. Then I noticed something, a bump inside the end of the bore. At first I thought that it was some dried Rocksett as I never had a chance to fire it after I put on the Blackout. Upon further inspection I noticed that this bump was on the exact opposite side of where the divot in the barrel is from being pinned. You can see it below in the photo. (don't mind the crusty crown, I still have to clean some Rocksett off)

This bump is on the land roughly 1/4-1/3" before the crown, I think that the white dot is a spec of dust. Obviously, I am freaking out a lot. I am a little puzzled because when the barrel was originally pinned the accuracy of the rifle was great as Scar 17s are. I'm wondering if it's not effecting accuracy or was it possible the pin got driven in farther when Adco removed it?? Now I'm also worried about a baffle strike when I get my SDN-6. No matter how you slice it I'm not feeling good about this.

 

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That SUCKS!
 
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Discussion Starter #3 (Edited)
I wonder if it will be ok like this or will I have to get it cut and do a re thread. Then if it's too short I'll have to get the Brakeout 2.0 permanently attached to avoid an NFA no no... ::FF::

I reckon it would be less expensive than a new barrel assembly.
 

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Discussion Starter #7
Somebody owes you a barrel, or at least the $$$ to buy another.

-SS
Sarge, I appreciate the reply. I can try and contact the guy who did it and show him the photo. I doubt he will respond or take responsibility, he is a couple of states away. The barrel was pinned roughly 2.5 years ago.

Do you think that it's worth salvaging the assembly with a cut and re thread?
 

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Try shooting it first and see how it does. I wouldn't expect to come out pleased, and I'd be worried about the chrome lining flaking there even if the accuracy was acceptable.
 

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There is another solution, which is to counter-bore the barrel to the depth of the bump.

My long range gun has a barrel I had done by John Whidden, the US National Long Range champion. One of his standard procedures is he counter bores all barrels a few inches deep, so when you clamp a front sight on the barrel, you don't create a tight spot right at the end. It also protects the muzzle crown. So this solution is doable, and would avoid having to re-cut the thread, or having to shorten the barrel.

Indeed, you could do one of two things: I'd first try to bore it to the groove diameter, so it still acts as freebore. I imagine you could just get a .308 reamer to do that. If you get ambitious, get a tool post grinder or a rotary clamp with a surface grinder, and you can actually grind a .300 pilot on the reamer, so it centers itself. Now the bullet will still be guided by what essentially is freebore. The other solution would be to overbore the diameter, so the counterbored section is like the throat of a flash suppressor

I agree with Sarge, that someone screwed this up and ought to owe you a barrel, but in case you don't get it, all is not lost. A HSS reamer in .308 is $25.

The only thing I'd be concerned about, and it is not a big concern, is that if the metal is thin enough that it peened inwards, after you finish your operation it might be REALLY thin. At the muzzle, you still get something like 12,000 PSI, so I'd wonder if the thin spot would start bulging out. Again, no issue - in the worst case, if it were a hole, it would act like a muzzle break.
 

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Reading your post gave me a knot in my stomach. I can only imagine how YOU feel. You have some sound advice above. Hope it works out for you.
 

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Discussion Starter #13
There is another solution, which is to counter-bore the barrel to the depth of the bump.

My long range gun has a barrel I had done by John Whidden, the US National Long Range champion. One of his standard procedures is he counter bores all barrels a few inches deep, so when you clamp a front sight on the barrel, you don't create a tight spot right at the end. It also protects the muzzle crown. So this solution is doable, and would avoid having to re-cut the thread, or having to shorten the barrel.

Indeed, you could do one of two things: I'd first try to bore it to the groove diameter, so it still acts as freebore. I imagine you could just get a .308 reamer to do that. If you get ambitious, get a tool post grinder or a rotary clamp with a surface grinder, and you can actually grind a .300 pilot on the reamer, so it centers itself. Now the bullet will still be guided by what essentially is freebore. The other solution would be to overbore the diameter, so the counterbored section is like the throat of a flash suppressor

I agree with Sarge, that someone screwed this up and ought to owe you a barrel, but in case you don't get it, all is not lost. A HSS reamer in .308 is $25.

The only thing I'd be concerned about, and it is not a big concern, is that if the metal is thin enough that it peened inwards, after you finish your operation it might be REALLY thin. At the muzzle, you still get something like 12,000 PSI, so I'd wonder if the thin spot would start bulging out. Again, no issue - in the worst case, if it were a hole, it would act like a muzzle break.
I sort of follow you but this might be beyond my abilities.
 

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I highly doubt this was done while removing the pin, but anything is possible. I'd send ADCO the pic. They are good guys who actually stand by their work. I bet they would have a solution whether it was their fault or something else.
Sorry this happened... sucks
 

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Discussion Starter #15
Yes, they are a good bunch at Adco. I already sent him the picture, they said to test fire it. They said that it will probably shoot just fine??

The problem is there is no where in my area that I can shoot past 100 yards. Even prior accuracy was great at 100 so I doubt that it would change now. It's when you stretch it out to 300-600, then what? I am still mostly concerned about a potential baffle strike.

I also sent the photo to the guy who did the pin job. I doubt that he will be sending me $1,200 for a new barrel assembly.
 

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OK... I have a suggestion, I work with micro machining components and some very fine critical areas on molds.
One could if you have the skills grind that area out just the dimple . It would take toolmaker ( steel surgeon ) steadiness ! I like what sarge & djv said also... Not familiar with Shooting sights reccomendation but sounds valid if that is what precision shooters do.... however most have custom SS barrels or other fine materials ? Counterboring chrome lining ??? may chip and or degrade the edge ( flame front is NOT our friend ) don't want to get into that conversation again. However best of luck with that one... The more I think about it, the more I like the 2 obvious paths to resolution.
1) shoot it and live with it
2) chop & re-thread & re crown
Plan C .... The gunshop actually gets back to you and offers to make it right ?
Maybe a deal can be worked out with them.
FN barrels are a premium price ( sucks ), I would ask Jim for help if your 1 of his customers ... nothing like needing a friend at a time like this.

Just an after thought, if you do get ambitious like SS said, and need a diameter changed by Toolroom equiptment , let me know I will handle changing reamer diameters for you no cost to you.

mjk1
 
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Yes, they are a good bunch at Adco. I already sent him the picture, they said to test fire it. They said that it will probably shoot just fine??

The problem is there is no where in my area that I can shoot past 100 yards. Even prior accuracy was great at 100 so I doubt that it would change now. It's when you stretch it out to 300-600, then what? I am still mostly concerned about a potential baffle strike.

I also sent the photo to the guy who did the pin job. I doubt that he will be sending me $1,200 for a new barrel assembly.
I would think that of there was an issue with accuracy it would show at 100 yards. Is your rifle still set up the same minus removing the barrel and putting it back on? It would be telling if there was a large POI shift.
 
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Discussion Starter #18 (Edited)
I would think that of there was an issue with accuracy it would show at 100 yards. Is your rifle still set up the same minus removing the barrel and putting it back on? It would be telling if there was a large POI shift.
Yes, same set up but I have heard that changing or removing the muzzle device can cause a slight POI shift. I also added a G trigger so this is also a variable but one in my favor.
 

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I over tightened ( like a fool ) my YHM QD mount and had all kinds of issues.... the biggie The SCAR would no longer group.... I was flipping OUT !
If I can help , let me know, I'm no fly by night moldmaker / toolmaker.
 
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