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Posted: 5/16/2009 12:27:18 PM EDT
| Ok my new too me ar (ea lower unknown carrytop upper 16" 556 barrel no m4 feedramps looks too be low round count on upper) has two problems it works as equiped single shot style kind of binds feeding the second round (short stroke ?) so having more than one ar on hand i swapped bcg and it ran fine. swap the bolt out of the non feeding ar into the other gun and it ran fine no problems (tells me its probably not a bolt problem ) other than that runs perfect lol |
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Swap the B/C's back and check the problem rig to see if the carrier alone is binding in the upper track, which would cause the short stroking problem.
As for the solution without a lot of fuss, you have already come up with it, and that is to just swap the B/C's like you did to get both rigs working. |
| thanks dano but it was a barrowed bolt carrier group with alot higher round count from the looks of it and id rather make mine work i tried a third bcg and it bump fired real bad scared the crap out of me and my bcg in that rifle worked fine mine was the only carbine in the group if that makes a differance ? |
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A carrier key being tight in the upper track, or slightly larger to cause some hammer wedging cycling problems is one thing, but when a carrier is causing bump firing, then its time to pull the FCG and confirm that those parts are installed correctly.
It almost sounds like either the hammer is on the boarder line of being loaded to the disc sear on cycle, or you have the disco spring either missing or installed upside down. Here is the link to the lower build so you can strip and reinstall the lower FCG. http://www.ar15.com/content/guides/assembly/lower/ |
| I had this prob.What i found was the buffer tube was not deep enough.With BCG pulled all the way back the bolt face was .030 from the BHO .So i used another complete lower/stock and checked,with the BCG pulled all the way back with the charging handle the bolt face was level with with the back of the ejection port and fired great no problems what so ever! I had the buffer bored with a bottom cutting end mill to make it deeper app..100 tho.and now she works great too .This is just somthing to check ,i read a lot on the Failure to eject,short cycling and Failure to load a new round.Mine was not a GAS problem ! |
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