Post by: Swannytheswan on March 12, 2013, 10:53:54 PM
Post by: ellensburgpo on March 13, 2013, 12:36:14 PM
Post by: demontang on March 14, 2013, 08:59:22 PM
Post by: HuntandFish on March 14, 2013, 10:01:31 PM
Good Luck!
H&F
Post by: mrolen on March 15, 2013, 09:20:50 AM
Post by: Swannytheswan on March 15, 2013, 10:12:47 AM
Post by: FALFire on March 15, 2013, 06:41:40 PM
Post by: Bone_Collector on March 16, 2013, 01:55:30 PM
B_C
Post by: demontang on March 16, 2013, 05:03:45 PM
Post by: Three_Oh_Eight on March 20, 2013, 12:35:30 AM
You may check the recoil buffer and spring. Maybe your MFG puts a stiffer spring or more weight in the buffer? This may be possible if your gas system is clean and your bolt carrier runs smoothly and is well lubricated.
Post by: Fl0und3rz on March 29, 2013, 12:03:05 AM
I have a BM predator that appears to have gas block/tube leakage that I need to correct (the issue described by prior owner was short-stroking with cheap 55 grain). In any event, check out the link below to try and approach the problem from an informed perspective.
http://www.ar15barrels.com/prod/operation.shtml (http://www.ar15barrels.com/prod/operation.shtml)
Post by: Swannytheswan on March 30, 2013, 02:30:30 PM
Post by: JLS on March 30, 2013, 02:44:07 PM
Post by: Swannytheswan on March 30, 2013, 03:20:23 PM
Post by: JLS on March 30, 2013, 03:42:52 PM
Have you taken the handguard off and inspected the gas tube?
Post by: Swannytheswan on March 30, 2013, 04:05:08 PM
Check your gas key again, clean it well, and lube the BCG well. What kind of oil are you using? Remoil is too light to use in an AR and will give you headaches.
Have you taken the handguard off and inspected the gas tube?
gas key is tight and well staked using CLP i did take off the hand guard and it looks ok to me but to be honest i don't know what to look for as i'm new to AR's
this is where i was
"Add more gas and the cartridge clears the action, but the bolt does NOT get far enough back to strip a round from the mag.
This is classic short stroking.
You have a single shot action which extracts and ejects, then closes on an empty chamber after you fire it.
In this condition, the bolt will also ride over an empty magazine and close on an empty chamber."
this is where i am with new buffer
"Add some more gas and you will reach the point where it feeds from the magazine and ALMOST works properly, but it still closes over an empty mag.
This is two things, first, poor mag springs are not pushing the follower up fast enough to catch the bolt and second, the bolt is not quite making it back far enough to catch on the magazine follower.
this is where i want to be
"Add just a little more gas and you are back to proper function."
Post by: JLS on March 30, 2013, 04:14:12 PM
I think there is likely something wrong with the internals, such as a misalignment or a gas leak.
Post by: Swannytheswan on March 30, 2013, 04:18:43 PM
Post by: NoImpactNoIdea on March 30, 2013, 05:18:30 PM
Post by: Heredoggydoggy on March 30, 2013, 05:38:52 PM
Did you buy the gun new? If so, did it ever function correctly? Without being able to put hands on it and what you have already checked I would be inclined to take off the gas block and see if the hole is the correct size or an obstruction in the tube.
Things to check: Gas block aligned with gas hole in barrel. If the gas block is off even a degree or so, it will cut down the pressure. 2 Clear gas hole in the barrel. Sometimes a chip from the manufacturing process gets lodged in the hole, cutting off some of the pressure. 3 as a last resort, try a different buffer TUBE. Lately some have got out without being drilled deep enough for the bolt to lock back.
ARs thrive on oil. The only place I'm careful not to put a lot of oil is the bore. Like I always tell people: If you are not getting oil flecks on your shooting glasses after the first shot--you're not using enough oil! :chuckle:
Post by: Swannytheswan on March 30, 2013, 06:28:08 PM
Did you buy the gun new? If so, did it ever function correctly? Without being able to put hands on it and what you have already checked I would be inclined to take off the gas block and see if the hole is the correct size or an obstruction in the tube.
I didn't buy it new I got it used but he said it was only 3 months old (4 now) and he said it ran 100% (no way of knowing really) When I first got it it ran perfect with 5.56 but would sometimes malfunction with .223 since then it has been malfunctioning with both (until I got the carbine buffer) I have been reluctant to take of the gas block but I guess that is what is next. What size should the hole be? how deep should the buffer tube be? as for oil I have had it well lubricated but not so much i am getting sprayed with it on the first shot( I'll hose her down tomorrow and see how she runs)
thanks for all the help
Post by: Heredoggydoggy on March 30, 2013, 06:59:56 PM
Post by: SGTDuffman on March 30, 2013, 09:15:13 PM
http://www.ar15.com/forums/t_3_66/567693_Ejection_Pattern_Question.html (http://www.ar15.com/forums/t_3_66/567693_Ejection_Pattern_Question.html)
Post by: Swannytheswan on March 30, 2013, 09:23:32 PM
How's the ejection? Check the pic in this link:
http://www.ar15.com/forums/t_3_66/567693_Ejection_Pattern_Question.html (http://www.ar15.com/forums/t_3_66/567693_Ejection_Pattern_Question.html)
i believe it would be right around the 4:30 mark not quite sure
Post by: NoImpactNoIdea on March 30, 2013, 09:25:46 PM
Did you buy the gun new? If so, did it ever function correctly? Without being able to put hands on it and what you have already checked I would be inclined to take off the gas block and see if the hole is the correct size or an obstruction in the tube.
I didn't buy it new I got it used but he said it was only 3 months old (4 now) and he said it ran 100% (no way of knowing really) When I first got it it ran perfect with 5.56 but would sometimes malfunction with .223 since then it has been malfunctioning with both (until I got the carbine buffer) I have been reluctant to take of the gas block but I guess that is what is next. What size should the hole be? how deep should the buffer tube be? as for oil I have had it well lubricated but not so much i am getting sprayed with it on the first shot( I'll hose her down tomorrow and see how she runs)
thanks for all the help
I dont know exactly the size of the gas hole in the barrel but I would just check to make sure that it is a round hole (no metal burrs) and that the gas block is lined up correctly. Even with a stock FSB and the pins they can be not exactly straight. If you are going to knock off the FSB be aware that the pins are tapered and will only go in and out one way! That may save a little frustration if it gets to that.
Post by: Swannytheswan on March 30, 2013, 09:28:44 PM
Did you buy the gun new? If so, did it ever function correctly? Without being able to put hands on it and what you have already checked I would be inclined to take off the gas block and see if the hole is the correct size or an obstruction in the tube.
I didn't buy it new I got it used but he said it was only 3 months old (4 now) and he said it ran 100% (no way of knowing really) When I first got it it ran perfect with 5.56 but would sometimes malfunction with .223 since then it has been malfunctioning with both (until I got the carbine buffer) I have been reluctant to take of the gas block but I guess that is what is next. What size should the hole be? how deep should the buffer tube be? as for oil I have had it well lubricated but not so much i am getting sprayed with it on the first shot( I'll hose her down tomorrow and see how she runs)
thanks for all the help
I dont know exactly the size of the gas hole in the barrel but I would just check to make sure that it is a round hole (no metal burrs) and that the gas block is lined up correctly. Even with a stock FSB and the pins they can be not exactly straight. If you are going to knock off the FSB be aware that the pins are tapered and will only go in and out one way! That may save a little frustration if it gets to that.
Good to know
Post by: SGTDuffman on March 30, 2013, 09:55:35 PM
Barrel Length (in) Barrel Diameter (in) Distance from Muzzle (in) Min Port Size (in) Max Port Size (in)
11.5 .625 3.850 .081 .089
11.5 .750 3.850 .086 .094
14.5 .625 8.375 .063 .078
14.5 .750 8.375 .070 .086
16 .625 8.375 .063 .078
16 .750 8.375 .070 .086
20 .625 6.875 .086 .093
20 .750 6.875 .093 .096
24 .825 N/A .089 .089
You might look into borrowing a buddies bolt carrier to see if that helps. I'm not positive but I thought Colt generally used FA style bolt carriers. A lighter bolt carrier may help, but that's a bit of an expense for troubleshooting.
http://www.ten-41.com/showthread.php?t=502 (http://www.ten-41.com/showthread.php?t=502)
Post by: Swannytheswan on April 02, 2013, 06:51:46 PM
(https://hunting-washington.com/smf/proxy.php?request=http%3A%2F%2Fi912.photobucket.com%2Falbums%2Fac326%2Fbswans%2FDSCN1875.jpg&hash=f906d2ca9b1cba5c2e4a166c7da7ffe2640e1522)
(https://hunting-washington.com/smf/proxy.php?request=http%3A%2F%2Fi912.photobucket.com%2Falbums%2Fac326%2Fbswans%2FDSCN1874.jpg&hash=5f8013116e33d61fa62a29e4be51e64987589655)
Post by: Heredoggydoggy on April 02, 2013, 07:10:52 PM
I think I found my problem but I don't know how to fix it. This looks like a gas leak to me am I correct or is this normal (don't know why I didn't see it when I took the hand guard off before). do I need a new gas tube or gas block? or is this a sign of a misaligned gas block (I don't have the punches to take the gas block off just yet I will get some soon)
(https://hunting-washington.com/smf/proxy.php?request=http%3A%2F%2Fi912.photobucket.com%2Falbums%2Fac326%2Fbswans%2FDSCN1875.jpg&hash=f906d2ca9b1cba5c2e4a166c7da7ffe2640e1522)
(https://hunting-washington.com/smf/proxy.php?request=http%3A%2F%2Fi912.photobucket.com%2Falbums%2Fac326%2Fbswans%2FDSCN1874.jpg&hash=5f8013116e33d61fa62a29e4be51e64987589655)
Looks like plenty of gas coming into the gas block/tube area. there is no gasket on the gas tube where it connects to the gas block. should be a roll pin holding them together. That might be an area to check, and make sure the gas block/gas tube connection is good. I had a bad connection there on my 6.8 SPC (my fault), so it does happen.
If you decide to remove that A2 sight/gas block. be aware that they are a tapered pin, and only go in/out one way. A support block is made expressly for that purpose, with a side marked "in" and a side marked "out" that the whole sight fits into, so you can't get it wrong.
Post by: Swannytheswan on April 02, 2013, 08:02:47 PM
Post by: Heredoggydoggy on April 03, 2013, 06:36:21 PM
Post by: Swannytheswan on April 03, 2013, 09:42:03 PM
Post by: Fisherdave10 on April 04, 2013, 01:27:56 AM
In my opinion, the two possibilities are 1) a gas leak at the front sight base or 2) an out of spec gas port drilled in the barrel.
There's no reason your rifle (especially since it's a Colt) shouldn't run with any new, domestically produced ammo from a reputable manufacturer.
Post by: Heredoggydoggy on April 04, 2013, 07:33:57 AM
Post by: Swannytheswan on April 04, 2013, 08:13:51 PM
Post by: Heredoggydoggy on April 04, 2013, 09:03:06 PM
mine is measuring at .180
OK, I just measured the YHM low-profile gas block and new gas tube that is waiting for my 6mmX6.8 SPC barrel to get here.
YHM gas tube hole measures .180, and the gas tube is a shy .180. If I recall from the other uppers I've built, the gas tube is a pretty snug fit in the gas block. You might have an out-of-spec gas tube.... :dunno:
Post by: Fl0und3rz on April 04, 2013, 09:29:04 PM
Post by: Swannytheswan on April 05, 2013, 03:50:07 PM
Post by: Big10gauge on April 05, 2013, 04:27:13 PM
Post by: Heredoggydoggy on April 05, 2013, 07:59:19 PM
Post by: Swannytheswan on April 05, 2013, 09:41:27 PM
Post by: Heredoggydoggy on April 06, 2013, 09:44:26 AM
i am wondering if my buffer spring is too heavy
That's a possibility...
Post by: JLS on April 06, 2013, 02:08:39 PM
i took out the gas tube from the gas block and you can clearly see the carbon ring around the hole in the gas tube where the it meets with the gas block and it is more or less concentric to the hole in the tube...i am wondering if my buffer spring is to heavy
Did the guy you bought it from modify it at all? I'm just having a hard time understanding why a Colt would have any ammunition issues. It should shoot whatever you feed it. Do you have a gunsmith you could take it to and have it checked out?
Post by: Swannytheswan on April 06, 2013, 02:49:58 PM
Post by: Heredoggydoggy on April 06, 2013, 05:46:44 PM
Post by: NoImpactNoIdea on April 06, 2013, 05:50:42 PM
OK--I think I see a problem. Looking at your pictures, I'm seeing a rub spot on the barrel between the sight-to barrel rings. And the front handguard mount doesn't look at all like the military style mount, so he had to remove the gas block to change the mounting piece from the barrel. If he drove the pins out towards the right, he blew out the tapered pin holes in the barrel by driving them out the wrong way. The pins that are in there now don't look like the right pins, so the hole in the barrel must be misaligned with the gas block hole. In other words, the pins should have been driven out right-to left. The rub spot on the barrel would indicate otherwise. The sad part is, it's not even a free-float handguard, so all that was gained are the picatinny rails. :sry:
The pins in it look correct to me (they may be in the opposite way - Large side on what was originally the small side based off the idiot marks but that wouldnt matter). I also dont think it would be possible to knock the pins out the wrong way since the FSB is cast metal and it would take more force to push them through than it would handle. The rub mark inside the FSB is most likely from a M4 stlye side sling adapter.
Post by: Heredoggydoggy on April 06, 2013, 05:56:34 PM
OK--I think I see a problem. Looking at your pictures, I'm seeing a rub spot on the barrel between the sight-to barrel rings. And the front handguard mount doesn't look at all like the military style mount, so he had to remove the gas block to change the mounting piece from the barrel. If he drove the pins out towards the right, he blew out the tapered pin holes in the barrel by driving them out the wrong way. The pins that are in there now don't look like the right pins, so the hole in the barrel must be misaligned with the gas block hole. In other words, the pins should have been driven out right-to left. The rub spot on the barrel would indicate otherwise. The sad part is, it's not even a free-float handguard, so all that was gained are the picatinny rails. :sry:
The pins in it look correct to me (they may be in the opposite way - Large side on what was originally the small side based off the idiot marks but that wouldnt matter). I also dont think it would be possible to knock the pins out the wrong way since the FSB is cast metal and it would take more force to push them through than it would handle. The rub mark inside the FSB is most likely from a M4 stlye side sling adapter.
The taper on those pins is very slight--almost imperceptible to the naked eye. I know, because I looked at the one that was removed from my barrel when I converted it to a free-float handguard and low-profile gas block.
Post by: Swannytheswan on April 06, 2013, 06:29:53 PM
OK--I think I see a problem. Looking at your pictures, I'm seeing a rub spot on the barrel between the sight-to barrel rings. And the front handguard mount doesn't look at all like the military style mount, so he had to remove the gas block to change the mounting piece from the barrel. If he drove the pins out towards the right, he blew out the tapered pin holes in the barrel by driving them out the wrong way. The pins that are in there now don't look like the right pins, so the hole in the barrel must be misaligned with the gas block hole. In other words, the pins should have been driven out right-to left. The rub spot on the barrel would indicate otherwise. The sad part is, it's not even a free-float handguard, so all that was gained are the picatinny rails. :sry:
I don't believe so that rub spot you are seeing is from the sling mount. to me it doesn't look like he removed the gas block...not saying he didn't but it doesn't appear that way to me
Post by: Swannytheswan on April 06, 2013, 06:41:08 PM
Post by: christopheri on April 06, 2013, 06:48:23 PM
I measured the pins and they are bigger on the right than on the left....Which according to almighty google is correct
I would pull the block off and make sure it doesnt have a restriction.
Post by: NoImpactNoIdea on April 06, 2013, 06:51:58 PM
OK--I think I see a problem. Looking at your pictures, I'm seeing a rub spot on the barrel between the sight-to barrel rings. And the front handguard mount doesn't look at all like the military style mount, so he had to remove the gas block to change the mounting piece from the barrel. If he drove the pins out towards the right, he blew out the tapered pin holes in the barrel by driving them out the wrong way. The pins that are in there now don't look like the right pins, so the hole in the barrel must be misaligned with the gas block hole. In other words, the pins should have been driven out right-to left. The rub spot on the barrel would indicate otherwise. The sad part is, it's not even a free-float handguard, so all that was gained are the picatinny rails. :sry:
The pins in it look correct to me (they may be in the opposite way - Large side on what was originally the small side based off the idiot marks but that wouldnt matter). I also dont think it would be possible to knock the pins out the wrong way since the FSB is cast metal and it would take more force to push them through than it would handle. The rub mark inside the FSB is most likely from a M4 stlye side sling adapter.
The taper on those pins is very slight--almost imperceptible to the naked eye. I know, because I looked at the one that was removed from my barrel when I converted it to a free-float handguard and low-profile gas block.
Ive built about 30 ARs and I agree that it is slight but you can see it with the naked eye. If you can pound it through the wrong way I wouldnt want to take a punch from you!
Post by: Heredoggydoggy on April 06, 2013, 06:52:47 PM
OK--I think I see a problem. Looking at your pictures, I'm seeing a rub spot on the barrel between the sight-to barrel rings. And the front handguard mount doesn't look at all like the military style mount, so he had to remove the gas block to change the mounting piece from the barrel. If he drove the pins out towards the right, he blew out the tapered pin holes in the barrel by driving them out the wrong way. The pins that are in there now don't look like the right pins, so the hole in the barrel must be misaligned with the gas block hole. In other words, the pins should have been driven out right-to left. The rub spot on the barrel would indicate otherwise. The sad part is, it's not even a free-float handguard, so all that was gained are the picatinny rails. :sry:
I don't believe so that rub spot you are seeing is from the sling mount. to me it doesn't look like he removed the gas block...not saying he didn't but it doesn't appear that way to me
I'm sorry if my post seemed a bit brusque, but the minute you said that the handguard had been changed, a red flag popped up. I'm by no means an expert AR-15 armorer, but after building my 4 ARs (4 1/2, if you count the parts that are waiting for the arrival of my 5th barrel), and seeing a lot of "Farmer Tight" mods to ARs, something is not right. That mounting plate between the gas block and barrel does not look like the one the military "clam-shell" handguard uses, and to change it, the sight/gas block would have to be removed. If the gun was As Factory, I would not be suspicious, but something is not right with the change, and I'm betting the trouble is there....
Post by: Swannytheswan on April 06, 2013, 07:01:39 PM
OK--I think I see a problem. Looking at your pictures, I'm seeing a rub spot on the barrel between the sight-to barrel rings. And the front handguard mount doesn't look at all like the military style mount, so he had to remove the gas block to change the mounting piece from the barrel. If he drove the pins out towards the right, he blew out the tapered pin holes in the barrel by driving them out the wrong way. The pins that are in there now don't look like the right pins, so the hole in the barrel must be misaligned with the gas block hole. In other words, the pins should have been driven out right-to left. The rub spot on the barrel would indicate otherwise. The sad part is, it's not even a free-float handguard, so all that was gained are the picatinny rails. :sry:
I don't believe so that rub spot you are seeing is from the sling mount. to me it doesn't look like he removed the gas block...not saying he didn't but it doesn't appear that way to me
I'm sorry if my post seemed a bit brusque, but the minute you said that the handguard had been changed, a red flag popped up. I'm by no means an expert AR-15 armorer, but after building my 4 ARs (4 1/2, if you count the parts that are waiting for the arrival of my 5th barrel), and seeing a lot of "Farmer Tight" mods to ARs, something is not right. That mounting plate between the gas block and barrel does not look like the one the military "clam-shell" handguard uses, and to change it, the sight/gas block would have to be removed. If the gun was As Factory, I would not be suspicious, but something is not right with the change, and I'm betting the trouble is there....
No offense taken I will pull it when I get some punches might even put on a low pro so I can put a scope on it...I called one of the guys that works at AR57 http://www.57center.com/] [url]http://www.57center.com/ (http://[url)[/url] and if I can't get it to run I will have him look at it
Post by: Heredoggydoggy on April 06, 2013, 07:12:30 PM
Post by: NoImpactNoIdea on April 08, 2013, 10:23:40 AM
Good deal--I'm glad you are on track to getting it fixed. The low-pro gas block I replaced my A2 sight with covers the barrel bands with the pin-holes, and has set-screws to affix it in the right spot, so if the pin holes are boogered, it won't mean the barrel is toast. :tup:
I think that this is the correct course of action. For the price of a low pro gas block (around $20)it would be worth it to me to try that (even if you want to keep a fab) before taking it to a smith. If that isnt the cause then you need to look at your bolt. Have you tried it with a different bcc?
Post by: JLS on May 16, 2013, 11:24:13 AM
Post by: Heredoggydoggy on May 16, 2013, 12:56:09 PM
Post by: mountainman on May 16, 2013, 08:58:49 PM