I had a BAR come in and it had quite the story. Was stolen, casing was unzipped and then it was stashed under a front porch in Florida. Was found 4 years later when someone hit the porch with a car and destroyed it. It had rusted to the open case. Guy brought it to me because he couldn’t keep the scope solidly mounted. It was pitted and even the aluminum receiver had pitting from the salt air here. While I had it we talked Cerakote to protect it, he was using charcoal grill paint. Sooooooo, I cleaned it up and Cerakoted it. Then put it back together. Made one mistake, removed the gas screw but put it back as close as possible before I Cerakoted. Also, plugged the piston housing and barrel so there was no chance of getting anything in ports. However, when I test fired a couple of rounds I didn’t check the cartridges. My bad.
Bottom line, shoots and cycles good, ejects properly, 2 things happening: 1) 3 shots, 2 inch group, about 4th shot 3 inches out, 2) every casing comes out flat on one side for about 1/8th of an inch from lip. My “guess” is a slight short cycle and bolt slows down enough for the ejector to take over and make case hit chamber before ejecting fully. Need to turn gas screw out a bit……I think.
Not sure how to explain the wild shot except he may have gotten excited. I bring it up because someone may have seen something like it before. He had only shot 10 rounds through it. So may not be as consistent problem as he implied.
Please let me know if you have any ideas what may be happening, especially on the flat casings. –KB
Bob covered this model in the pro course. He recommended glass bedding the stock to the frame for strength and accuracy.
The case neck is most likely hitting something during ejection. Any brass mark on any part of the rifle? You can use the tape method to see whether this short cycling. –TL
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I’d call the 4th shot a flyer due to barrel heating. BAR’s have a fairly wimpy barrel, so it’s not a surprise. Case mouth is likely hitting the edge of the ejection port, not unusual for a semi auto, and not normally a problem. DC
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Most of the time the only thing that matters is that the gun functions all the time. If it does who cares about the brass. If you are getting a flyer then you should bed the stock, try it out. If you still get the flyer pressure bed the barrel. That should take care of most things. Also, don’t forget to check that everything is tight. Loose stock screw or something like that can lead to a flyer. Ken actually talked about this in the last http://classes.agiprostudents.com/
It would be worth checking out. RJ
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If it extracts, ejects and locks open when the last round is fired it isn’t short cycling. The flat spot on the case is from the case spinning around and hitting the receiver somewhere……not really important where. Poor accuracy could be from many things, loose or poorly bedded stocks, bore bulged/rung, bore rusty, etc. Ken
