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I took apart my BCA upper to install a new barrel.
Just a wild guess from being a professional wrench jockey for 10 years, id say it was on there with 100 foot pounds and it looked like red loctite.
First of all, WHY?
Second, is it possible the upper receiver is damaged from this?
I tried to lap the barrel mating face with 600 grit, after several minutes I was left with a somewhat shiney surface and 2 large grooves in it.
I filed the grooves down so I no longer could catch a finger nail in it and restarted the lapping process.
Is this thing doomed, or should I give it a try and see if it works?
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You could give it a try and if it turns out it is a problem then you could pick up a Anderson stripped upper for cheap and move on.
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stripped uppers are cheap, i would just buy one and move on
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gofastman Wrote:First of all, WHY? Because it is in manufacturers interests not to have things come loose when sold as a complete upper.
Second, is it possible the upper receiver is damaged from this? Depends on how you isolated the torque. Did you clamp the barrel?
Is this thing doomed, or should I give it a try and see if it works? Give it a try and see how it groups.
..
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A5BLASTER Wrote:You could give it a try and if it turns out it is a problem then you could pick up a Anderson stripped upper for cheap and move on.
Wow, I didn't realize they were that inexpensive.
Considering the amount of force it took to separate this thing, I just decided to order a new one.
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I took apart my BCA upper when I first got it to lap the receiver and bed the barrel extension. No thread locker on mine, but it did take ~120 ft-lbs to remove the barrel nut. I was surprised there were any threads left, but the anodizing was still intact. I put it all back together and it's working fine, though I'm not convinced that my upper receiver isn't slightly twisted because of it, as indicated by how much windage adjustment my scope needs to center it up.
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trace Wrote:I took apart my BCA upper when I first got it to lap the receiver and bed the barrel extension. No thread locker on mine, but it did take ~120 ft-lbs to remove the barrel nut. I was surprised there were any threads left, but the anodizing was still intact. I put it all back together and it's working fine, though I'm not convinced that my upper receiver isn't slightly twisted because of it, as indicated by how much windage adjustment my scope needs to center it up.
Wow 120 ftlbs that's just stupid high. If I'm not mistaken spec is 30 to 90 for standard barrel nuts that the gas tube goes throw.
I think I would replace the upper if it had that much torque on it.
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I don't doubt 120 at all. It was freaking on there good!
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Oh man I had Spikes upper that a gorilla must had assembled on a 11.5" FN barrel, when it didn't go easy at first I broke out the heat gun and a 2' cheater pipe. Still had to jump on the monkey bar to get it to break free, sometimes it is what it is. Seems over the years even on lower torqued barrels the feel of the initial pop to break the nut free always seems harder than what it took to set it in the first place.
