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FTF issues on new 308 build


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I have seen this thread before and I don't want to beat a dead horse … I chose and posted here because this group seems to be the most patient with the new guys which is me because all my uppers are complete just exploring changing barrels and stuff, but I have built several AR15s in both 223 and 300blk no issues with the 223 had and solved 300blk issues with a different spring to use sub-sonic out of pistol gas system FTF issues. So moved on to bigger and better the AR10 as I have always loved the 308 win thinking maybe using for hunting so I bought an Aero  M5E1 Enhanced 20" .308 CMV Quantum Handguard Complete Upper installed a Brownell's BCG and Radian charging handle on a 5D tactical lower with Geissele  rapid fire trigger and used Aero lower parts and Aero M5 308 carbine buffer tube and spring. 

I have seen threads and don't want rehash but there were two issues

1. when pulling charging handle back it would not hold open but did close and chamber 1st round and would continue to fire before failing to feed, it would also lock open when last round was fired,   I did see else where some info about the bolt catch and using a threaded bolt catch pin which made sense some as the catch pin went in way easier than any of the AR15s I have assembled ??? 

2.  I had intermittent FTF as the round would get stuck half way up the feed ramp, the gun would run 4 or 5 rounds and then FTF. Tried different mags and was using Remington core lok 150 grain was able borrow and try some Seller and Bellot 200 grain. 



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3 hours ago, lots/learn said:

when pulling charging handle back it would not hold open but did close and chamber 1st round and would continue to fire before failing to feed, it would also lock open when last round was fired,

It should catch if it catches after last round, are you sure you are depressing the catch far enough manually? Check the interface between the magazine and the catch. I have had a magazine/catch combo where the magazine stopped the catch from making it's full movement.

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Thank you in advance …all help and advice would be much appreciate!!

 I will admit when I ran it the first time it was oiled but not really wet with oil!

I'm learning but feel more like an adult model builder as I take parts and put them together where many here do a lot more but hopefully in time with practice  , anyways I took some pictures as suggested I tried to show the bolt catch area of the lower because what stood out to me when putting the parts together is there wasn't the tension when trying to get the bolt catch pin in, i.e. when assembling AR15 you need to place a punch or something through the whole as the buffer is pushing against the catch … with this build I matched the catch wholes with the lower holes and slide the pin in there seemed way to easy from experiences with AR15 builds! 

The other thing is this lower is a 5D tactical and the area on the lower that accepts the bolt catch seemed different than what I seen in terms of the installing the catch, the catch is an Aero sorry the picture kind of sucks.

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