Mods, if this is the wrong location please move, and I apologize in advance.
I recently assembled my pistol build lower receiver, and I am having issues with it accepting magazines, and feeding properly. I bought a Seekins precision SBA15 billet stripped lower from my LGS during the concern in the fall. At the same time I bought a BCM enhanced lower parts kit with the PNT trigger to go with it.
A few weeks ago I decided to finally put everything together. Now, this is my first time assembling an AR lower 100% by myself. I checked pages here, watched some youtube videos from some respected channels, and tried to remember exactly how it all goes, and got to work. The very first problem I ran into was installing the magazine release. The SBA15 has a pre-installed ambi bolt catch held in place by a tensioning screw. It's also a tad oversized, so I made do with what I could on the magazine release and moved onto the rest of the lower. I realized soon after that I would have to remove the bolt catch to get the magazine catch in properly. So I removed it, and screwed in the mag catch, making sure it aligned with the button. Inserted a gen 2 pmag, and it locked up nice and tight. I finished putting everything together after that.
Did most of my function tests (minus the feed test because I can't find my dummy rounds) and we were all clear. I took it out to my range to get my T1 zeroed and to get everything fully function tested out. Using a gen 2 windowed Pmag, with ZQI 62 gr 5.56 the first shot goes bang, no problem. I could feel the BCG not go into battery though, so I slingshot the charging handle, and once again bang, but same feeding issue. It would not chamber a new round, and it looked to be catching on the top of the magazine. I grab one of my lancer mags, same problem. I can't tell why it seems to be sitting higher? The Seekins billet lower doesn't play well with gen 3 pmags, nor any magazine with the overinsertion tab. Last night I dug into it again, and twisted the magazine latch back a few spots, which seemed to seat the mags more comfortably, however, i have to slam empty mags into it to seat on a closed bolt. This is beyond my noob abilities here, so I would love some feedback. I messaged Voodooman last night on Instagram to pick his brain on proper buffer, and buffer springs he uses.
EDIT*Since taking these pictures I have re-cleaned and lubed the rifle properly. It still feels like it's cycling slow however, but I will not be able to actually take it to the range until this weekend. I also unthreaded the magazine catch a few more rungs, but the gun still hates dealing with empty mags on a closed bold because I think the mags are sitting too high personally. Also for you guys running the Law folder and shockwave system on these pistols, what buffer weight and spring types work best for reliable cycling?*
SPECS:
Lower: Seekins SBA15 Billet lower receiver, BCM Enhanced LPK W/PNT trigger, Law tactical folder, shockwave brace, shockwave CARBINE buffer and standard spring, shockwave pistol buffer tube. https://www.kakindustry.com/shockwav...ve-package-fde
Upper: Used LMT 10.3 with FSB I received in trade, my BCM bolt, BCG, firing pin, etc.
TL;DR: I can't figure out what I am doing wrong on my lower that I assembled, and why it's failing to seat, failing to feed, and getting hung up on magazines, and I feel really stupid, please help.
20170605_193517 by Willis, on Flickr
20170605_193522 by Willis, on Flickr
20170605_193513 by Willis, on Flickr
20170605_193416 by Willis, on Flickr
20170605_193037 by Willis, on Flickr
20170605_192723 by Willis, on Flickr
20170605_174919 by Willis, on Flickr
20170605_174843 by Willis, on Flickr
20170605_174641 by Willis, on Flickr
20170605_174323 by Willis, on Flickr
20170605_174313 by Willis, on Flickr
20170605_174243 by Willis, on Flickr
20170605_174238 by Willis, on Flickr
20170605_174043 by Willis, on Flickr
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