BUmmedic

It's been all quiet for a bit now... I have an open ticket without response regarding the BCG and receiver wear. I have a Tubb spring coming this week, but it'll be a bit before I have a chance to test it out. I'm hoping that helps. As others have said, it seems to run fine, and maybe I'm making a mountain out of a mole hill.

Here are some additional pics. First are buffer and spring, now that I look at it, maybe 26 coils (if I'm even counting correctly). 11.25" long. Buffer 2.5" and 3.8 oz. Other pics show spring out, buffer in, and carrier placed on top and bottomed out. Shows clearance between carrier and receiver. So unless the buffer end is impacting the tube and compressing, there shouldn't be impact between the carrier and lower.

Read up on them... will probably be the first thing I'll try once I hear back from Aero. Thanks!

Honestly, for the price I paid for all the parts, I can't complain, but I guess for extra I could have tried to get the peace of mind of a factory build, but I've seen bad stuff happen with those, too. At least I'm learning a ton by riding this wave...

What have I gotten myself into? :-P

Well, due to the abnormal wear on the lower and upper, it looks like Aero may want it back for warranty/repair, so I'll let you all know what they say. I'm waiting for CS to respond to my open ticket.

Thanks for all of the excellent info... I will post a pic of my spring the next chance I get. I may very well be counting the coils incorrectly, but from what I have read about coil counting (yes, I looked it up), then it may actually be less than 27. Does the material at the end of the buffer actually compress? Read somewhere about Sprinco springs (the ORANGE one, in particular)... found a couple forum threads that made me question its utility... "flavor of the month" was a term I read. Oh well, I'll post a pic of my spring and maybe it really is a couple coils short despite the length being ok.

Best as I can measure: 1. 7" 2. 2.5" and 3.8 oz 3. 11.25" and 27 coils

But if the carrier doesn't contact the lower with only the buffer sitting in the tube, I don't see how live fire would allow it to go further and make contact unless every shot is allowing the buffer or tube to compress or elongate and plastically deform and rebound (I'm not a physics or engineering major, but something tells me a 7075 mil-spec tube won't do that). If it will, please someone school me... I've always been a good student.

Maybe I spoke too soon?

Saw these peening marks on the rear of the lower also on either side of the buffer. Cerakote is being stripped away a bit. Definitely impact marks. No noticeable damage to carrier body.

Thanks! Can't wait to get it back out there again!

Ha ha! Love it!

I don't care so much about the port, it's the case head/ejector swipes and forward ejection pattern that initially got me questioning. The port wear was just an after-the-fact finding. I get that the cases are striking there and the deflector, which is what I expect them to do.

Oh, it gets sprayed down to dripping, wiped (great way to keep the rag soaked), and then sprayed again to dripping before being reassembled. It may not be dripping down my arm, but it's wet. Sorry if it came across as otherwise.

Thanks for the responses, guys... I'm starting to think it's nothing to worry or right home about. I don't know about the "running down my arm" wet, but I use a healthy mixture of Rem-Oil and MPro7 on a soaked rag to wipe down all parts once they're clean... gets them nice and slick, before reassembling and wiping them down again and spraying them with Rem-Oil aerosol and putting it all back together. I've never had a problem, plus, I can take the aerosol with me to the range to spray down as I see fit during shooting, and before running a patch or bore snake for a provisional clean before packing up and heading home. I've never tried the Castrol or Mobil-1 treatment, but a lot of guys I know like it. Thanks again!

Took my M5E1 build (all Aero parts unless otherwise specified) out yesterday for the first time: matched M5E1 ODG cerakote receivers with 15" M-Lok hand guard, 16" QPQ barrel, low pro GB, melonite gas tube, LPK, nitride BCG, A2 flash hider, carbine buffer kit, Troy BUIS, Magpul CTR/MOE grip/AFG, and some Ergo rail panels. One failure to feed in first 10 rounds, the remainder up to 60 fed, fired, and ejected. Ejection pattern pretty consistent in the 1:30-3:00 position, about 4-5 feet away. Used two types of brass factory ammo, both NATO FMJ - one mil-surplus and one ZQi Guardian. No reloads. I've shot this through my .308 20" rifle, which shows a pretty consistent 4:30-5:00 ejection pattern at same 4-5 foot distance. Brass was also showing extraction claw on some, ejector swipes pretty consistently, mild denting of case mouth on some of the ZQi, mild denting just below shoulder on a few from both batches. No blown/bulging/flattened primers that I could see. Have never fired a 16" .308, so recoil was definitely sharper (which is what I expected). Also appears that the cases are striking the rear of the ejection port opening and stripping some of the cerakote finish away. I contacted Aero and they suggested firing some heavier-grain .308 commercial ammo to compare, but it does kind of bother me that there may be an issue with this thing shooting run-of-the-mill FMJ. Is this something that I should worry about and troubleshoot? I've already gotten suggestion for an adjustable gas block from one of my buddies. I have no problem doing that, but don't want to fix what ain't broken, or miss something else that may be a bigger problem. Thanks in advance!