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Post by viper06 on Nov 19, 2013 18:41:40 GMT -8
I finally received everything in to start my new build and 1st one with a BHW barrel. It's a 20' bull barrel. I'm having some serious issues with the rifle feeding and since I have no experience with these barrels I'm hoping someone can help. I just assembled the rifle and when I release the charging handle to load a round it sticks as the round starts to enter the chamber. I can pull the charging handle back again and release it and the round will finish loading. It's the factory 123 Hornady Amax ammo. After I eject the rounds they have gouges down the bullet and on the neck of the case and dents in the shoulder of the case caused by the feed ramps on the barrel. There is also material from the bullets left of the feed ramps. I've built about 20 ARs and never had anything like this happen. Any advice would be greatly appreciated. Thank you.
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Deleted
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Post by Deleted on Nov 19, 2013 19:04:51 GMT -8
I finally received everything in to start my new build and 1st one with a BHW barrel. It's a 20' bull barrel. I'm having some serious issues with the rifle feeding and since I have no experience with these barrels I'm hoping someone can help. I just assembled the rifle and when I release the charging handle to load a round it sticks as the round starts to enter the chamber. I can pull the charging handle back again and release it and the round will finish loading. It's the factory 123 Hornady Amax ammo. After I eject the rounds they have gouges down the bullet and on the neck of the case and dents in the shoulder of the case caused by the feed ramps on the barrel. There is also material from the bullets left of the feed ramps. I've built about 20 ARs and never had anything like this happen. Any advice would be greatly appreciated. Thank you. It sounds like you have a bolt problem. Check the ejector. I would bet it is catching on the rim of the loaded round as it is trying to feed. This is a common problem with the Grendel / LBC case.
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Post by viper06 on Nov 21, 2013 5:45:14 GMT -8
Thanks for the reply. I tried swapping bolts, complete BCG, and I put the upper on one of my lowers with it's BCG from the same rife that works perfectly and no go! Still having the same issue. I'll try tinkering with it some more this afternoon, but I'm still stumped.
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45r
New Member
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Post by 45r on Dec 1, 2013 21:34:25 GMT -8
You might want to put a bevel on your ejector where it faces the brass upon feeding. Dehorning or polishing any areas where brass is rubbing sometimes helps. Some say polishing the bolt face can help. Check your feed lips on mag and see if the bullet tips are centered towards feed ramps. Might need to tweak them and or smooth them if they have sharp edges. The 6.5G/264LBC sometimes needs a little bolt and mag mods.
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Post by Old Desert Rat on Dec 4, 2013 0:09:56 GMT -8
I finally received everything in to start my new build and 1st one with a BHW barrel. It's a 20' bull barrel. I'm having some serious issues with the rifle feeding and since I have no experience with these barrels I'm hoping someone can help. I just assembled the rifle and when I release the charging handle to load a round it sticks as the round starts to enter the chamber. I can pull the charging handle back again and release it and the round will finish loading. It's the factory 123 Hornady Amax ammo. After I eject the rounds they have gouges down the bullet and on the neck of the case and dents in the shoulder of the case caused by the feed ramps on the barrel. There is also material from the bullets left of the feed ramps. I've built about 20 ARs and never had anything like this happen. Any advice would be greatly appreciated. Thank you. I'm not saying this is directly related to your situation, but I just helped a buddy who recently received a DPMS LR260 (260REM) upper. He bought it as a long range upper, since these 6.5mm cartridges with long VLD bullets shoot fast and stay supersonic out past 1000 yards. But those VLD bullets turned out to be a problem. The standard 308 barrel extension has feed ramps that were designed for bullets like the .308 168gr SMKs. My buddy couldn't get ANY of his 260REMs with 142 SMKs to feed. In fact, most of the bullets were pushed far enough back to crush a lot of the Varget and rattle around loose! I verified that by using my finger through the ejection port to act like the bolt and push the rear of a cartridge forward. Sure enough, the feed ramps were NOT forcing the bullets inward past the rear edge of the chamber, allowing them to slam into the flat rear face of the barrel. Turns out that the smaller .264 bullet diameter, combined with its very long VLD ogive, let it slip down deep into the locking lug cutout in the feed ramps. That sliced nice deep gouges into the bullets, then let their points (meplats) slam into the flat back of the barrel, at least .050 outside the generous chamfer at the back of the chamber. The point they touched rear flat of the barrel had copper marks, and the angle matched the flat that was pounded into the bullet points of the damaged cartridges. My friend asked me to grind some "secondary feed ramps" into the barrel itself. After I was sure he understood the risk, I did that. I used a 3/16" dia. Dremel to grind and polish ramps that extend .080" into the chamber and out into the rear face. I also worked the rear edges of the lucking lug cuts, rounding them and polishing them so that they would not gouge his bullets. His cartridges now feed reliably. They now have visible but MUCH lighter gouges from the lug cuts, and they do get a little ding on their points from slamming into that secondary ramp, but that's hell and gone better than getting shoved all the way back into the case! Points are: 1) You can test yours the same way, and see how the bullets feed. 2) I'm NOT advocating that anyone else take a grinder to their barrel chambers!! But I am beginning to think that the standard 308-based feed ramps may not be shaped correctly to EVER feed smaller diameter VLD bullets; If no manufacturer is willing to experiment and make it work, they should consider advertising that their barrels/uppers/guns are NOT suited for VLD bullets. And I think that would be the kiss of death.
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Post by GLSHOOTER on Dec 4, 2013 8:38:40 GMT -8
Actually the OP had to rework the ejector/extractor on his bolt. Once Ritch talked him through it he was GTG. Those big, short fat cases in that little bolt don't have much wiggle room and if you look at them in action the feed ramnps don't hardly touch anything at all. That whole cartridge is almost completely airborn during part of the cycle.
Greg
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