jebarton3 Posted November 18, 2016 Report Share Posted November 18, 2016 (edited) So I had my 308 sbr out at the range after building it recently and at first I was having feeding issues. It would double feed rounds and I was tearing up brass. I adjusted the gas block so that the rifle would feed and after around 20 rounds the casings will now instead of ejecting they will just spin around in the upper causing it to chew up the brass and causing it to jam up. am I needing to adjust my gas block to where I need more or less gas? Or could it be something different? Thanks guys. Edited November 18, 2016 by jebarton3 Quote Link to comment Share on other sites More sharing options...
MikedaddyH Posted November 18, 2016 Report Share Posted November 18, 2016 Maybe more weight in the buffer would slow down the BCG. Keep the gas turned up enough to eject the brass. Quote Link to comment Share on other sites More sharing options...
jebarton3 Posted November 18, 2016 Author Report Share Posted November 18, 2016 I am currently running a hydraulic buffer. you believe I should go with a heavy buffer? Quote Link to comment Share on other sites More sharing options...
MikedaddyH Posted November 18, 2016 Report Share Posted November 18, 2016 1 hour ago, jebarton3 said: I am currently running a hydraulic buffer. you believe I should go with a heavy buffer? SS chime in ! Do you have a "standard" buffer ? Try that first ! I am not a fan of using only one part of a "system", that hydraulic buffer might be your problem. Quote Link to comment Share on other sites More sharing options...
jebarton3 Posted November 18, 2016 Author Report Share Posted November 18, 2016 What is the other part of said system? I have a heavy buffer also so I can give that a try if I can get a chance to hit the range this weekend. Quote Link to comment Share on other sites More sharing options...
shepp Posted November 18, 2016 Report Share Posted November 18, 2016 3 minutes ago, jebarton3 said: What is the other part of said system? I have a heavy buffer also so I can give that a try if I can get a chance to hit the range this weekend. I would assume spring and buffer Quote Link to comment Share on other sites More sharing options...
Matt.Cross Posted November 18, 2016 Report Share Posted November 18, 2016 Hydraulic buffer is a mistake, use the heavy buffer and tune your gas system to it. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted November 18, 2016 Report Share Posted November 18, 2016 10 hours ago, jebarton3 said: So I had my 308 sbr out at the range after building it recently and at first I was having feeding issues. It would double feed rounds and I was tearing up brass. I adjusted the gas block so that the rifle would feed and after around 20 rounds the casings will now instead of ejecting they will just spin around in the upper causing it to chew up the brass and causing it to jam up. am I needing to adjust my gas block to where I need more or less gas? Or could it be something different? Thanks guys. That's a magazine issue. Period. Change mags and use a mag that feeds reliably. Open the gas port all the way up. Conduct testing. If it's not cycling properly like that ^^^ - then get back with details of what it's doing. Double-feeds are ONLY a magazine problem. Quote Link to comment Share on other sites More sharing options...
jebarton3 Posted November 18, 2016 Author Report Share Posted November 18, 2016 1 hour ago, 98Z5V said: That's a magazine issue. Period. Change mags and use a mag that feeds reliably. Open the gas port all the way up. Conduct testing. If it's not cycling properly like that ^^^ - then get back with details of what it's doing. Double-feeds are ONLY a magazine problem. Brand new 10 round pmags. Quote Link to comment Share on other sites More sharing options...
jtallen83 Posted November 18, 2016 Report Share Posted November 18, 2016 12 hours ago, jebarton3 said: So I had my 308 sbr out at the range after building it recently and at first I was having feeding issues. It would double feed rounds and I was tearing up brass. I adjusted the gas block so that the rifle would feed and after around 20 rounds the casings will now instead of ejecting they will just spin around in the upper causing it to chew up the brass and causing it to jam up. am I needing to adjust my gas block to where I need more or less gas? Or could it be something different? Thanks guys. Define "spin around" and "chew up". Is the extractor coming off the rim before complete extraction or is the case coming out of the chamber but staying in the rifle after extraction? Pictures would be a big help. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted November 19, 2016 Report Share Posted November 19, 2016 (edited) 17 hours ago, jebarton3 said: Brand new 10 round pmags. That's cool - with brand new springs, that have never been cycled, until you loaded them, right? Magazines get "broken in" as well as all other moving parts. Double Feeds are always a magazine problem. Double Feed - two live rounds trying to enter the chamber at the same time. ^^^ If you have one spent round that didn't extract or eject, and a live one trying to feed, that's not a Double Feed... That's a different malfunction. Edited November 19, 2016 by 98Z5V Quote Link to comment Share on other sites More sharing options...
jebarton3 Posted November 19, 2016 Author Report Share Posted November 19, 2016 1 hour ago, 98Z5V said: That's cool - with brand new springs, that have never been cycled, until you loaded them, right? Magazines get "broken in" as well as all other moving parts. Double Feeds are always a magazine problem. Double Feed - two live rounds trying to enter the chamber at the same time. ^^^ If you have one spent round that didn't extract or eject, and a live one trying to feed, that's not a Double Feed... That's a different malfunction. I wish I had gotten pictures but after reading your reply it makes more sense. So it's not trying to load 2 live rounds the spent casing that should be ejected is just spinning around instead of ejecting out and causing it to jam. the part of the casing that is getting "chewed" up is the neck and mouth area. probably from the bolt coming forward. Quote Link to comment Share on other sites More sharing options...
washguy Posted November 19, 2016 Report Share Posted November 19, 2016 (edited) Jeb lets go back to square one.......one round in mag....charge....fire....does the bcg lock back/hold on the bolt catch? Wash pics would help...and put the correct buffer and buffer spring back in the tube.....you using a car stock or rifle? car stock spring roughly 111/4 inches long for an ar 308....car buffer bout 2.5 inches long for an ar308 take a look at your extractor for bits of brass and also look to see if some nitwit didnt put 2 doughnuts in there...we have seen that before Edited November 19, 2016 by washguy Quote Link to comment Share on other sites More sharing options...
98Z5V Posted November 20, 2016 Report Share Posted November 20, 2016 7 hours ago, jebarton3 said: So it's not trying to load 2 live rounds the spent casing that should be ejected is just spinning around instead of ejecting out and causing it to jam. the part of the casing that is getting "chewed" up is the neck and mouth area. probably from the bolt coming forward. One of two things is going on here, based on this description - it's under gassed, and the BCG isn't fully cycling, which is causing the round to not clear the ejection port (low bolt carrier speed, due to under-gassing). OR, its weak extraction, with the extractor is letting go of the spent case before it's fully clearing the chamber - then it just bounces around and doesn't get ejected. One quick test to see which one it is - open that gas block ALL the way up, chamber one round, as Wash stated, and see if it locks back after firing. If it does, you're not under-gassed, and it's a weak-extractor problem. Solved, pending shooting result. Quote Link to comment Share on other sites More sharing options...
Matt.Cross Posted November 20, 2016 Report Share Posted November 20, 2016 Don't forget the hydraulic buffer is a component. Those things are worthless... Quote Link to comment Share on other sites More sharing options...
survivalshop Posted November 20, 2016 Report Share Posted November 20, 2016 Also , disassemble the Bolt Components & inspect & clean . New Components could have Burr's or Debris from machining . Look closely at the Ejector & Extractor & their respective Springs . DPMS Extractor has a double spring , Spring within a Spring . Other manufacturers may use just one Spring & an O-ring ( Donut ) or two , I recommend the DPMS Spring system . What Gas system is your SBR barrel ? Quote Link to comment Share on other sites More sharing options...
Tacky Posted December 4, 2016 Report Share Posted December 4, 2016 On 11/18/2016 at 4:22 AM, jebarton3 said: So I had my 308 sbr out at the range after building it recently and at first I was having feeding issues. It would double feed rounds and I was tearing up brass. I adjusted the gas block so that the rifle would feed and after around 20 rounds the casings will now instead of ejecting they will just spin around in the upper causing it to chew up the brass and causing it to jam up. am I needing to adjust my gas block to where I need more or less gas? Or could it be something different? Thanks guys. I ran into a similiar issue on a 20" barrel in 243 recently. They gas hole was drilled at .0980" and when firing the rim of the case was being ripped off, as others have stated the brass in the chamber had expanded from firing and had not retracted yet when the bolt was attempting to extract it. I opted for a SLR rifleworkw sentry S9 adjustable gas block. The detents allow it to be set with positive setting. Its low profile fit under the midwest ss gen 2 308 rail. Currently have it set on on setting 5, reduced recoil impulse, and no more double feeds, stove pipes,, or ripped rims. I recommend them. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted December 5, 2016 Report Share Posted December 5, 2016 3 hours ago, Tacky said: I ran into a similiar issue on a 20" barrel in 243 recently. Comparing the gas system operation on a 20" barreled .243 to the gas system operation on a.308 SBR is like comparing apples to oranges apples to hammers. Nothing to do with each other, in the least. It contributes nothing to this guy's problem - and he still hasn't responded back yet... Quote Link to comment Share on other sites More sharing options...
Tacky Posted December 5, 2016 Report Share Posted December 5, 2016 I was referencing the same rip case rim issue, thats the same regardless of barrel length or gas system length. If your gas port is to large on a rifle length system, it has the same result as a pistol length gas system thats overgassed, case destruction, large part of the bolt carrier hitting the receiver near the buffer tube threads, etc. I have built and used both, and witnessed first hand. Until you have witnessed this on a rifle length system you have no idea what I speak of. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted December 5, 2016 Report Share Posted December 5, 2016 42 minutes ago, Tacky said: I was referencing the same rip case rim issue, thats the same regardless of barrel length or gas system length. If your gas port is to large on a rifle length system, it has the same result as a pistol length gas system thats overgassed, case destruction, large part of the bolt carrier hitting the receiver near the buffer tube threads, etc. I have built and used both, and witnessed first hand. Until you have witnessed this on a rifle length system you have no idea what I speak of. Show me your 308 SBR then. That you witnessed this on. Quote Link to comment Share on other sites More sharing options...
Tacky Posted December 5, 2016 Report Share Posted December 5, 2016 I do not personally own a lr308 308win sbr, my reason, I have no use for one, it does not make effective use of the powder and you lose to much velocity, and tend to blind yourself with the muzzle flash. But since you seem to be implying I have no experience with gas guns here is my collection of ar platform rifles, I built each and every one. Quote Link to comment Share on other sites More sharing options...
DNP Posted December 5, 2016 Report Share Posted December 5, 2016 Quote Link to comment Share on other sites More sharing options...
98Z5V Posted December 5, 2016 Report Share Posted December 5, 2016 (edited) 41 minutes ago, Tacky said: I do not personally own a lr308 308win sbr, my reason, I have no use for one, it does not make effective use of the powder and you lose to much velocity, and tend to blind yourself with the muzzle flash. Okay, so you don't own one, a 308SBR, but you're trying to compare YOUR issue to his. And, you have zero relative basis. Zero. But you thought you'd make it all better, by telling what your 243, 20" barrel did. And it doesn't compare, not even slightly. That's like telling a guy how your Barrett 50BMG is doing when he's asking about a problem with his Ruger 10/22 - literally. Oh, and a pic of my rifle collection would embarrass you. You know, since we're comparing dick size and rifle-problem-diagnosis-experience on the pictures of our rifle collection... Edited December 5, 2016 by 98Z5V Quote Link to comment Share on other sites More sharing options...
Tacky Posted December 5, 2016 Report Share Posted December 5, 2016 I tend to just bow out, and say since your the expert, and you seem to know everything there is to know about the ar platform, and that your collection would embrass me , I applaud you for being a genius, may the AR gods shine bright light on you and your words. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted December 5, 2016 Report Share Posted December 5, 2016 Hey, that's cool - that's usually how people that talk alot of schit tend to honorably take it - once they realize that they're not the smartest person in the room, and their game is told... Honorable people, like you. I'm not saying I know ANYTHING about a .308 Win SBR. All I'm saying is that your contribution about your 20" barreled .243 Win RIFLE doesn't have a damn thing to do with this man's issue with his .308 Win SBR. Glad you realized that your contribution, as well as you intended it, didn't have a single thing to do with this man's problem with his particular rifle and caliber - even though it still might run through the same receivers. Apples to Hammers, man. They're not all the same. Glad you finally caught on.. Have a great night. Quote Link to comment Share on other sites More sharing options...
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