As some of you know, I am a certified armorer. I don't work for a gun shop or make any money whatsoever by wrenching on AR's. I simply got certified for my own fulfilment and because I enjoy it. Over the years, I've built alot of rifles, both for myself and others. I've also worked on and troubleshot many as well. I also frequently offer a helping hand on occasion to folks who need a little help, don't have the expertise or tools necessary to do the job. Whatever the job may be.
As a result, I've seen some crazy stuff over the years. Much of it is the stuff you hear about, but think it's a one in a million chance of ever happening to you. I can only imagine what guys who do this for a living see on a daily basis. Because I've seen alot and this is just a hobby for me.
I'm also one of those guys that often recommends higher end gear or often has a low opinion of low end, inexpensive or unknown manufacturers. Some probably consider me a brand snob. I can assure you, that's not the case. My opinions and recommendations usually come from first hand experiences, both good and bad.
Tonight, we're going to look at one of the bad ones. I got a message yesterday from a friend that I've helped many times before. In fact, the upper I worked on for him tonight, I have built and rebuilt on three different occasions. Now, my friend has a young child and life circumstances dictate that he be economical. I've always been willing to offer advice or opinion, while remaining respectful of the fact that he couldn't just slap together an upper with all the most expensive, high speed parts on the market. His gun, his choice. Whatever he wanted, we built.
Last year, we converted his 16" 5.56 upper into a 300blk SBR. Budget dictated that he purchase a barrel from a newcomer to the AR world. An unproven and relatively unknown manufacturer, who appeared on the scene around 2013. The only problem was that he couldn't get the 8" cmmg barrel that he really wanted, so he went a different route.
Recently, he was able to pick up the cmmg barrel that he originally wanted for the low, low price of $100. Awesome. So when all of the parts arrived, he shot me a message and build #3 was underway!
Tonight, after getting the kiddos tucked in for the night, I headed out to the garage. I recently added baby #2 to the roster, so I haven't had much time on the bench since March. I was looking forward to the project. I got all the tools out & arranged on the bench. Next, I laid out the parts for the upper and mounted my reaction rod in the vise. Now, it was time to get down to business.
First order of business was to tear down the upper, remove the gas block, barrel nut and pull the old barrel. Starting with the muzzle device, I slid my armorer's wrench into place and slowly started to turn. To my surprise, the wrench turned much easier than expected. Maybe 5-10 lbs of torque. I looked at the barrel and saw this:
Uh oh, something's hinky. The muzzle device had not moved at all, but the barrel was turning easily in the upper. That's never a good sign.
So I turned the wrench as if I were tightening the muzzle device and it returned to TDC. Strange. I decided to turn my attention to the barrel nut, so I could remove the entire barrel assembly and get to bottom of what was going on. Barrel nut spun off without issue and a normal amount of torque. So I pulled the barrel. Then, I found this:
Obviously, it wasn't unthreaded this much when it came off, just loose. The barrel extension spun off the end of the barrel easily. If you're not aware, the barrel extension torque spec is something in the neighborhood of 200 ft lbs. They aren't supposed to come off, ever. Certainly not with the minimal effort I put into it. The only good news here, is that I was able to slip the barrel nut off the back end of the barrel and I didn't have to remove the gas block. That chore in particular, was one I was dreading. Why? Because I installed the last one. And I don't intend for them to come loose, like... Ever. Problem solved, I didn't have to fool with it now.
Now granted, if the owner was pulling the barrel for any reason other than to replace it, we would have had a real problem on our hands. And his gun would have been down for the count for however long it will take the manufacturer to replace it. That's assuming they will replace it. They should and I hope they do, as it is obviously defective.
Note to self, this is NOT how your upper should come apart:
Some of you may be wondering, how does this happen? Well, there are really only two ways. #1) it was simply not torqued correctly at the manufacturer. This is a QC issue and wholly unacceptable. Or #2) improper nitride. This is a common issue, especially with lesser known, low cost manufacturers. You see, the nitride process involves heat, alot of it. A properly assembled nitride barrel should have the barrel extension installed AFTER nitride. Why? Because the process introduces salts and heat to the steel. Both of which can lead to loosening of the barrel extension if it's installed prior to treatment.
So, here's a good example of why I caution folks from always choosing the cheaper, deal of the day parts. Sometimes, you do actually get what you pay for. In this case, it could have been catastrophic. Because a loose barrel extension can increase headspace, which sooner or later can lead to a not-so-fun demonstration of the effects of PSI vs the strength of steel and aluminum... Right next to your face. And this concludes tonight's episode of "Adventures in AR Smithin". Good night and God Bless America...
As a result, I've seen some crazy stuff over the years. Much of it is the stuff you hear about, but think it's a one in a million chance of ever happening to you. I can only imagine what guys who do this for a living see on a daily basis. Because I've seen alot and this is just a hobby for me.
I'm also one of those guys that often recommends higher end gear or often has a low opinion of low end, inexpensive or unknown manufacturers. Some probably consider me a brand snob. I can assure you, that's not the case. My opinions and recommendations usually come from first hand experiences, both good and bad.
Tonight, we're going to look at one of the bad ones. I got a message yesterday from a friend that I've helped many times before. In fact, the upper I worked on for him tonight, I have built and rebuilt on three different occasions. Now, my friend has a young child and life circumstances dictate that he be economical. I've always been willing to offer advice or opinion, while remaining respectful of the fact that he couldn't just slap together an upper with all the most expensive, high speed parts on the market. His gun, his choice. Whatever he wanted, we built.
Last year, we converted his 16" 5.56 upper into a 300blk SBR. Budget dictated that he purchase a barrel from a newcomer to the AR world. An unproven and relatively unknown manufacturer, who appeared on the scene around 2013. The only problem was that he couldn't get the 8" cmmg barrel that he really wanted, so he went a different route.
Recently, he was able to pick up the cmmg barrel that he originally wanted for the low, low price of $100. Awesome. So when all of the parts arrived, he shot me a message and build #3 was underway!
Tonight, after getting the kiddos tucked in for the night, I headed out to the garage. I recently added baby #2 to the roster, so I haven't had much time on the bench since March. I was looking forward to the project. I got all the tools out & arranged on the bench. Next, I laid out the parts for the upper and mounted my reaction rod in the vise. Now, it was time to get down to business.
First order of business was to tear down the upper, remove the gas block, barrel nut and pull the old barrel. Starting with the muzzle device, I slid my armorer's wrench into place and slowly started to turn. To my surprise, the wrench turned much easier than expected. Maybe 5-10 lbs of torque. I looked at the barrel and saw this:
Uh oh, something's hinky. The muzzle device had not moved at all, but the barrel was turning easily in the upper. That's never a good sign.
So I turned the wrench as if I were tightening the muzzle device and it returned to TDC. Strange. I decided to turn my attention to the barrel nut, so I could remove the entire barrel assembly and get to bottom of what was going on. Barrel nut spun off without issue and a normal amount of torque. So I pulled the barrel. Then, I found this:
Obviously, it wasn't unthreaded this much when it came off, just loose. The barrel extension spun off the end of the barrel easily. If you're not aware, the barrel extension torque spec is something in the neighborhood of 200 ft lbs. They aren't supposed to come off, ever. Certainly not with the minimal effort I put into it. The only good news here, is that I was able to slip the barrel nut off the back end of the barrel and I didn't have to remove the gas block. That chore in particular, was one I was dreading. Why? Because I installed the last one. And I don't intend for them to come loose, like... Ever. Problem solved, I didn't have to fool with it now.
Now granted, if the owner was pulling the barrel for any reason other than to replace it, we would have had a real problem on our hands. And his gun would have been down for the count for however long it will take the manufacturer to replace it. That's assuming they will replace it. They should and I hope they do, as it is obviously defective.
Note to self, this is NOT how your upper should come apart:
Some of you may be wondering, how does this happen? Well, there are really only two ways. #1) it was simply not torqued correctly at the manufacturer. This is a QC issue and wholly unacceptable. Or #2) improper nitride. This is a common issue, especially with lesser known, low cost manufacturers. You see, the nitride process involves heat, alot of it. A properly assembled nitride barrel should have the barrel extension installed AFTER nitride. Why? Because the process introduces salts and heat to the steel. Both of which can lead to loosening of the barrel extension if it's installed prior to treatment.
So, here's a good example of why I caution folks from always choosing the cheaper, deal of the day parts. Sometimes, you do actually get what you pay for. In this case, it could have been catastrophic. Because a loose barrel extension can increase headspace, which sooner or later can lead to a not-so-fun demonstration of the effects of PSI vs the strength of steel and aluminum... Right next to your face. And this concludes tonight's episode of "Adventures in AR Smithin". Good night and God Bless America...
