JRoss Posted March 27, 2016 Author Report Share Posted March 27, 2016 47 minutes ago, survivalshop said: Does it lock back with just an empty mag. when pulling the Charging handle back all the way ? Do you have a 308AR Bolt Stop installed, they have a larger pad then the AR 15. Do you know the measurement from the center of hole to end of bolt stop by chance? Quote Link to comment Share on other sites More sharing options...
JRoss Posted March 27, 2016 Author Report Share Posted March 27, 2016 Yes it has the 308 bolt stop Quote Link to comment Share on other sites More sharing options...
JRoss Posted March 27, 2016 Author Report Share Posted March 27, 2016 Installed spring from my ar15 that measures 11 inches but left the 308 buffer in and loaded 2 rounds in mag. Rifle cycled both rounds but did not hold bolt open with empty mag. So with a lighter spring it cycles, thinking I may have to shorten buffer Quote Link to comment Share on other sites More sharing options...
washguy Posted March 28, 2016 Report Share Posted March 28, 2016 (edited) 6 hours ago, JRoss said: Installed spring from my ar15 that measures 11 inches but left the 308 buffer in and loaded 2 rounds in mag. Rifle cycled both rounds but did not hold bolt open with empty mag. So with a lighter spring it cycles, thinking I may have to shorten buffer Jross so lets back up...you now have an ejecting and firing rifle whereas before it just stove piped wouldnt feed deal...so you fixed that part with the ejector extractor...and you did what with the extractor doughnut spring wise? and you also put on the adjustable gas block ? so do you have the adj gas block wide open and it doesnt hold back even with two different types of springs...but its ejecting...not stove piping...right? so now that problem is solved...right? so did you think to turn down the gas with that big ol oversized gas port in the barrel ? its now cycling but just not holding back on last round right? how strong was it ejecting...should have been spitting them a ways off? you know you can have a catch not holding back with a rifle thats way overgassed you need to get the proper spring which is the one you had..not the ar15 spring...and you shouldnt have to be cutting on a buffer Wash LR-308 Standard Length Buffer DPMS 5.285" Long 5.41 Ounces 308 Standard Buffer Spring Length - 12.75'', 39 coils. Edited March 28, 2016 by washguy Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 28, 2016 Report Share Posted March 28, 2016 9 hours ago, JRoss said: Do you know the measurement from the center of hole to end of bolt stop by chance? Nope & I don't have a 308 bolt stop not in a Rifle . As shown , correct buffer spring for a DPMS type 308AR , Rifle Stock ,is around 12 3/4" long & has 39 coils , anything else may cause issues . I think the one from my 20" being 12 1/2 " long is with in spec for a well used Spring , most likely it needs replacing. I would adj. the Gas Block per manufacturers instructions , as has been said above . BCG moving too fast & bouncing off the bottom of the Receiver Extension could overcome the Bolt Stop , I've seen them break . Quote Link to comment Share on other sites More sharing options...
JRoss Posted March 28, 2016 Author Report Share Posted March 28, 2016 1 hour ago, washguy said: Jross so lets back up...you now have an ejecting and firing rifle whereas before it just stove piped wouldnt feed deal...so you fixed that part with the ejector extractor...and you did what with the extractor doughnut spring wise? and you also put on the adjustable gas block ? so do you have the adj gas block wide open and it doesnt hold back even with two different types of springs...but its ejecting...not stove piping...right? so now that problem is solved...right? so did you think to turn down the gas with that big ol oversized gas port in the barrel ? its now cycling but just not holding back on last round right? how strong was it ejecting...should have been spitting them a ways off? you know you can have a catch not holding back with a rifle thats way overgassed you need to get the proper spring which is the one you had..not the ar15 spring...and you shouldnt have to be cutting on a buffer Wash LR-308 Standard Length Buffer DPMS 5.285" Long 5.41 Ounces 308 Standard Buffer Spring Length - 12.75'', 39 coils. Extractor is inner and outer spring with oring, I left it alone. It was ejecting a good 4 feet. The gas block is full open and bolt does not stay open after firing last round in mag. With the 308 Standard Buffer Spring Length - 12.75'', 39 coils. and buffer at 4.8 ounces that came with the rifle and the adjustable gas block installed and following manufactures instructions on adjustment of gas the bolt did not stay open after round fired and mag empty. I should get a 5.41 ounce buffer and spring like the ones you have listed above and start all over again with the adjustment of the gas block. The buffer I have now is just over a half ounce lighter and maybe that is enough to cause problems with not holding the bolt open. Quote Link to comment Share on other sites More sharing options...
washguy Posted March 28, 2016 Report Share Posted March 28, 2016 (edited) Jross but you do have the correct rifle buffer its length is 5.28 ? did you ever turn down the gas block to where the rifle wouldnt cycle?....and then start opening it? how open is your gas block? If it were me I would get me a tubbs flatwire spring...same spring for car or rifle..it slows things down...i like em. Oh snap.... went back and read that your gas block is wide open...start closing it down....but you still need the right spring and buffer...you said it cycled with the longer 308 spring...take out the ar15 spring and put back in the longer 308 spring what is your thinking on why the rifle stopped its failure to feed and bending the cartridge? Wash Edited March 28, 2016 by washguy Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 28, 2016 Report Share Posted March 28, 2016 (edited) How far does your Gas Tube protrude into the Upper Receiver ? Can you get a photo of it for us . Another thing is , you may have a fitment problem out of spec Bolt Stop . Even though you can manually engage it & it hold the BCG , it may have a Burr or may not be able to have full travel . I can pull one of mine off to get the measurement that you wanted . If you can Charge the Action & manually engage the Bolt Stop & it function as to spec's , there is nothing wrong with the Buffer system travel , doesn't rule out something else with in the system . Are there any marks on the threads for the Receiver Extension , where the BCG could be hitting ? You are close to a fully functional rifle , if its only the Bolt stop not engaging properly , but there is one thing bothering me & that is , with that big Gas Port in the Barrel , why is there not signs of over gassing ? It should be pounding the action back . May have something to do with Gas Tube length , there are two different lengths of Rifle length Gas Tubes , one is DPMS & the other is AR 10( Armalite ). Edited March 28, 2016 by survivalshop Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 28, 2016 Report Share Posted March 28, 2016 (edited) Like this Edited March 28, 2016 by survivalshop Quote Link to comment Share on other sites More sharing options...
JRoss Posted March 29, 2016 Author Report Share Posted March 29, 2016 On 3/28/2016 at 7:55 PM, washguy said: Jross but you do have the correct rifle buffer its length is 5.28 ? did you ever turn down the gas block to where the rifle wouldnt cycle?....and then start opening it? how open is your gas block? If it were me I would get me a tubbs flatwire spring...same spring for car or rifle..it slows things down...i like em. Oh snap.... went back and read that your gas block is wide open...start closing it down....but you still need the right spring and buffer...you said it cycled with the longer 308 spring...take out the ar15 spring and put back in the longer 308 spring what is your thinking on why the rifle stopped its failure to feed and bending the cartridge? Wash 15 hours ago, survivalshop said: How far does your Gas Tube protrude into the Upper Receiver ? Can you get a photo of it for us . Another thing is , you may have a fitment problem out of spec Bolt Stop . Even though you can manually engage it & it hold the BCG , it may have a Burr or may not be able to have full travel . I can pull one of mine off to get the measurement that you wanted . If you can Charge the Action & manually engage the Bolt Stop & it function as to spec's , there is nothing wrong with the Buffer system travel , doesn't rule out something else with in the system . Are there any marks on the threads for the Receiver Extension , where the BCG could be hitting ? You are close to a fully functional rifle , if its only the Bolt stop not engaging properly , but there is one thing bothering me & that is , with that big Gas Port in the Barrel , why is there not signs of over gassing ? It should be pounding the action back . May have something to do with Gas Tube length , there are two different lengths of Rifle length Gas Tubes , one is DPMS & the other is AR 10( Armalite ). I have a DPMS Buffer and Spring coming, might have it by the weekend. They should be the 5.28 length and 5.41 ounce weight and 12.75 length and 39 coils as advertised and will check them before installing. I will follow the manufactures gas block adjustment instructions with the new parts installed. The gas tube slips into the gas key 3/8" when bolt is fully closed. My camera doesn't take very clear close up pics so cant send pic. The gas tube I have installed measures 15 3/16" and an AR10 is 15 1/2". The extra 5/16" in the AR10 tube length will be too long and would bottom out in the gas key when the bolt is fully closed from the measurements I took. A 15 3/8" would work and not bottom out in gas key. I don't know if the 3/8" engagement into the gas key (which is what the rifle has now) is correct. Maybe if I find a parts Tech. who would measure one at 15 3/8" and have them send it. I don't see any marks on the receiver extension threads. My thinking on the stop of the FTF and cycling correctly is the AR15 spring installed was 11 inches long so the pressure on the bolt changed with a shorter spring and allowed the bolt to move back farther before being pushed back forward by the spring. Also with the adjustable gas block installed the gas pressure could have changed allowing different bolt speed pushing back into the spring. Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 29, 2016 Report Share Posted March 29, 2016 (edited) By just visual inspection , does the Gas Tube sit in the Upper like the photo above ? The Gas Tube should be in the middle of the Cam Pin recess in the Upper as in the photo . Is the Bolt Stop easy to move with no binding , the Magazines spring is kinda weak when the Follower is at the top of the Mag. & any binding will not permit the Bolt stop to raise enough to engage the Bolt . Is the correct Spring in use for the Bolt Stop , it can be confused in the Lower Receiver parts group . Edited March 29, 2016 by survivalshop Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 29, 2016 Report Share Posted March 29, 2016 (edited) On March 27, 2016 at 10:46 AM, JRoss said: Do you know the measurement from the center of hole to end of bolt stop by chance? The Pin hole to the long end of the Bolt Stop as best as I can measure is 0.900" & the short end is 0.120" These measurements are not exact but close, had a hard time getting centered in the Pin hole. Edited March 30, 2016 by survivalshop Quote Link to comment Share on other sites More sharing options...
JRoss Posted March 30, 2016 Author Report Share Posted March 30, 2016 15 hours ago, survivalshop said: The Pin hole to the long end of the Bolt Stop as best as I can measure is 0.0900" & the short end is 0.120" These measurements are not exact but close, had a hard time getting centered in the Pin hole. OK so in fractions the 0.0900" is about 3/32" and 0.120" is about 1/8" does that sound about right? The gas tube does not extend to the middle of the Cam Pin recess. I have checked the bolt catch and everything looks right and moves easily. When the bolt is latched all the way back and held by the bolt catch the bolt can still be pulled back another 3/8" so the present buffer is not too long. The Mag follower spring is tight when Mag is empty and presses firmly on the bolt catch........... Here is something everyone should try with their AR if they already have not done so. First be sure the gun is empty of ammunition and no round in the chamber, second remove the magazine from the well, third pull the charging handle back and depress the bolt catch to keep the bolt in the open position, forth check again to be sure the gun is unloaded, and fifth grab the hand guard and slam the butt of stock on the floor.........does the bolt slam shut on your gun? Quote Link to comment Share on other sites More sharing options...
washguy Posted March 30, 2016 Report Share Posted March 30, 2016 (edited) Jross.....maybe thats why your $hit dont work...you keep slamming your $hit to the floor? my $hit doesnt ef up up when I take the car butt stock and hammer it on the hood of my of my zo6...and nothing happens,,,its the molecular make up of a chopper gun fiberglass hood resonating with the polyacrylamide I guess? Wash Edited March 30, 2016 by washguy Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 30, 2016 Report Share Posted March 30, 2016 (edited) 7 hours ago, JRoss said: OK so in fractions the 0.0900" is about 3/32" and 0.120" is about 1/8" does that sound about right? The gas tube does not extend to the middle of the Cam Pin recess. I have checked the bolt catch and everything looks right and moves easily. When the bolt is latched all the way back and held by the bolt catch the bolt can still be pulled back another 3/8" so the present buffer is not too long. The Mag follower spring is tight when Mag is empty and presses firmly on the bolt catch........... Here is something everyone should try with their AR if they already have not done so. First be sure the gun is empty of ammunition and no round in the chamber, second remove the magazine from the well, third pull the charging handle back and depress the bolt catch to keep the bolt in the open position, forth check again to be sure the gun is unloaded, and fifth grab the hand guard and slam the butt of stock on the floor.........does the bolt slam shut on your gun? Need to see a photo of where your Gas Tube is positioned in the Upper Receiver , use a flash light if not enough light for a clear photo . Take a photo of you Bolt Face with the EMPTY Mag in the rifle holding the Bolt Catch engaged with the Bolt also. This build of yours is why we recommend using Receivers from the same manufacturers , Tolerance stacking can make even your best efforts useless . I find it strange that with that large of Gas Port in the Barrel that you are not witnessing heavy recoil when firing , even with the inside diameter of the gas tube @ 0.120" which is a reduction of your Barrels Gas Port hole , but you should be over gassed , something is not correct , of course. Are you holding the Bolt Catch in while you are slamming your rifle down ? If not , they will all drop the BCG , maybe even with a empty Mag installed , most may drop the BCG . Its not what the Bolt Catch is designed for . I have no desire to try this test. If I remember correctly , this is a 80% Lower receiver you finished , no offense to you, but it is a possability that you finished spec's may not be correct & it may be effecting you Bolt Catch engagement. The Bolt Catch travel can altered if not raising enough to engage the Bolt Face properly. The 0.900" is almost an inch , I put a zero where it didn't belong.I fixed it . Edited March 30, 2016 by survivalshop Quote Link to comment Share on other sites More sharing options...
beantown Posted March 30, 2016 Report Share Posted March 30, 2016 The BCG should go forward if no magazine is in it and you slam the butt stock on the floor. Butt stock hits floor, BCG over rides the recoil spring tension, bolt catch drops out of the way and the bolt slams home. Even Army issued M16/M4 will do it. As stated before the bolt catch is not designed to hold the bolt open, if you bounce the rifle off the floor, with no magazine in it. Quote Link to comment Share on other sites More sharing options...
JRoss Posted March 31, 2016 Author Report Share Posted March 31, 2016 15 hours ago, survivalshop said: Need to see a photo of where your Gas Tube is positioned in the Upper Receiver , use a flash light if not enough light for a clear photo . Take a photo of you Bolt Face with the EMPTY Mag in the rifle holding the Bolt Catch engaged with the Bolt also. This build of yours is why we recommend using Receivers from the same manufacturers , Tolerance stacking can make even your best efforts useless . I find it strange that with that large of Gas Port in the Barrel that you are not witnessing heavy recoil when firing , even with the inside diameter of the gas tube @ 0.120" which is a reduction of your Barrels Gas Port hole , but you should be over gassed , something is not correct , of course. Are you holding the Bolt Catch in while you are slamming your rifle down ? If not , they will all drop the BCG , maybe even with a empty Mag installed , most may drop the BCG . Its not what the Bolt Catch is designed for . I have no desire to try this test. If I remember correctly , this is a 80% Lower receiver you finished , no offense to you, but it is a possability that you finished spec's may not be correct & it may be effecting you Bolt Catch engagement. The Bolt Catch travel can altered if not raising enough to engage the Bolt Face properly. The 0.900" is almost an inch , I put a zero where it didn't belong.I fixed it . The 80% lower I finished did not require any machine work involving the bolt catch mechanism or mag well machining. All the 80% lowers I have held in my hands did not require any bolt catch mechanism machining but that does not mean there are not any out there that do. I don't really consider this my "build" (as people like to refer to the assembly process and I find amusing, no offense intended) because I did not build the barrel or bolt or the trigger or the springs or the pins or the gas tube or the buffer or anything else. All I did was "assemble" the lower with parts some other people built. I attached the upper that some more people built. I installed a mag that some other people built. All this crap that was built by some other people other than myself did not work very good when the trigger I did not "build" (I am guilty of pulling it) was pulled. An automobile goes down an assembly line with many people involved, a person buys the car and drives it. They did not build it. They put gas in it and if it breaks down the mechanic who fixes it would not say " I built the car". Its like when I hear someone talk about a "re-weld" gun. It was only welded once so why would it be called a "re-weld"? So I will just keep plugging away at this rifle. I really appreciate all the input and knowledge that people here on this forum share! Remember the Johnny Cash song "One Piece at a Time" ? Quote Link to comment Share on other sites More sharing options...
JRoss Posted March 31, 2016 Author Report Share Posted March 31, 2016 11 hours ago, beantown said: The BCG should go forward if no magazine is in it and you slam the butt stock on the floor. Butt stock hits floor, BCG over rides the recoil spring tension, bolt catch drops out of the way and the bolt slams home. Even Army issued M16/M4 will do it. As stated before the bolt catch is not designed to hold the bolt open, if you bounce the rifle off the floor, with no magazine in it. I was waiting for a "no" answer so we could help someone fix their rifle ;) Quote Link to comment Share on other sites More sharing options...
washguy Posted March 31, 2016 Report Share Posted March 31, 2016 Jross. Put a tubbs spring in it and turn down the gas till it wont hardly cycle then turn it up a lil till it does...what ammo you been using? Wash Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 31, 2016 Report Share Posted March 31, 2016 6 hours ago, JRoss said: The 80% lower I finished did not require any machine work involving the bolt catch mechanism or mag well machining. All the 80% lowers I have held in my hands did not require any bolt catch mechanism machining but that does not mean there are not any out there that do. I don't really consider this my "build" (as people like to refer to the assembly process and I find amusing, no offense intended) because I did not build the barrel or bolt or the trigger or the springs or the pins or the gas tube or the buffer or anything else. All I did was "assemble" the lower with parts some other people built. I attached the upper that some more people built. I installed a mag that some other people built. All this crap that was built by some other people other than myself did not work very good when the trigger I did not "build" (I am guilty of pulling it) was pulled. An automobile goes down an assembly line with many people involved, a person buys the car and drives it. They did not build it. They put gas in it and if it breaks down the mechanic who fixes it would not say " I built the car". Its like when I hear someone talk about a "re-weld" gun. It was only welded once so why would it be called a "re-weld"? So I will just keep plugging away at this rifle. I really appreciate all the input and knowledge that people here on this forum share! Remember the Johnny Cash song "One Piece at a Time" ? No one is blaming you for any of this , you have to understand that the building ( or assembling ) of a 308AR is not like its little brother where they are assembled with parts that are designed to a MilSpec & all are exactly the same to those spec's . The 308AR components are what ever the manufacturer decides they are . The thing about the 80% Lowers are that the machining one does on them can directly effect other functions of the rifle , if not correctly machined , be it the Jig imperfections or how it is placed or attached . A reweld firearm is one that was cut in half per the Gov. de-mill program & welded back together & re-registered with the BATF to make it a working firearm . I had one, an FN-FAL HB select fire rifle & it worked great . You say your Gas Tube doesn't sit in the Middle of the of that notch in the Upper Receiver , a little off is no big deal, but if its at one end or the other , it could cause issues. I have seen Barrels that were manufactured with the Gas Block stop Flange on the Barrel was not machined correctly & no Gas Tube made would work correctly with it , because it aligned the Gas Tube in the Upper Receiver too far forward to give the proper gas signal to the BCG . Some we have found the AR 10 Gas Tube which is a little longer then the std AR Gas Tube ( DPMS uses std AR 15 Gas Tubes ) is needed or thats the spec's the manufacturer designed or machined the Gas Block Flange to use an AR 10 Gas System or just screwed the pooch . When you cycle the Charging handle , is there much resistance or does it cycle smoothly , with just the slight feel of the Hammer being cocked ? You say your not building the rifle & just a parts assembler , well just reading this Thread sounds like your into more then just assembling Parts . Quote Link to comment Share on other sites More sharing options...
JRoss Posted April 2, 2016 Author Report Share Posted April 2, 2016 On 3/30/2016 at 9:44 PM, washguy said: Jross.....maybe thats why your $hit dont work...you keep slamming your $hit to the floor? my $hit doesnt ef up up when I take the car butt stock and hammer it on the hood of my of my zo6...and nothing happens,,,its the molecular make up of a chopper gun fiberglass hood resonating with the polyacrylamide I guess? Wash Wash.....you aint slammin that $hit hard enough! Lemme see that that thing I will show you some $hit! Quote Link to comment Share on other sites More sharing options...
JRoss Posted April 2, 2016 Author Report Share Posted April 2, 2016 On 3/31/2016 at 9:33 PM, washguy said: Jross. Put a tubbs spring in it and turn down the gas till it wont hardly cycle then turn it up a lil till it does...what ammo you been using? Wash Been trying some Lake City Match with adjustable block Quote Link to comment Share on other sites More sharing options...
JRoss Posted April 2, 2016 Author Report Share Posted April 2, 2016 Survivalshop.....Thanks for the length tip difference in the AR10. I found this thread here. https://forum.308ar.com/topic/7135-ar-10-vs-dpms-gas-tubes-ftf-issue/?page=1 Gonna try and get one at 15 1/2" Quote Link to comment Share on other sites More sharing options...
washguy Posted April 2, 2016 Report Share Posted April 2, 2016 1 hour ago, JRoss said: Wash.....you aint slammin that $hit hard enough! Lemme see that that thing I will show you some $hit! Lol. Okay Jross... ill slam it harder Get that damn thing runnin...will ya Wash Quote Link to comment Share on other sites More sharing options...
JRoss Posted April 3, 2016 Author Report Share Posted April 3, 2016 Got my new buffer and spring in the mail. Was making a trip into town so I called ahead to a shop in and asked if they had a AR10 gas tube and if it measured 15 1/2", the guy said yes so I asked if he could hold it for me and would be there in an hour. I get there and tell him I called about the tube so he hands me the tube and I get my tape measure out and guess what............. it measures 15 3/16". I wanted to say something smart a$$ but didn't knowing it wouldn't make the tube grow any. I just asked if he could get one or order one in. Don't think that will happen either. The Big Reno Show is next weekend and they advertise 1& 1/2 acres of exhibitors, anyone wanna put odds on finding a 15 1/2" gas tube in the mess? Quote Link to comment Share on other sites More sharing options...
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