Yoda

Survivalshop, I'll likely trim the feed ramps and polish them. I'd like all mags to work eventually. Hopefully the metal mags work for now. The bolt/extractor seems to work fine when I drop a round in by hand. The cartridge base has no problem entering the bolt face and extracting. Hopefully by the end of this week or early next week I can find the culprit. thanks

That's interesting Wash. I can see copper on my barrel extension so it looks like the rounds are hitting it hard. I'll order a Lancer for testing also. Thanks!

Just ordered a few ASC mags. Look forward to seeing if/how they work. Hopefully this is the problem although I love Magpul magazines. I guess worse case I can sell my 6 Magpul magazines here. I sent pics to Aim, Mega and Aero to see what they think about the feed ramps/chamber. I measured the ramps at .222" wide. Seem pretty small. I'll post more info as I get it. thanks!!!

The extractor works fine. When I help a round into the chamber i can extract it normally. The ramps are definitely a problem: Here's a shot of the bolt spacing with the ch-handle locked back. It looks fine to me. Everything is Aero precision M5 parts except the barrel which is Mega so the spring/buffer are M5 kit parts. I tried releasing the ch-handle from all the way back, pressing the bolt stop and letting slam forward and helping it forward to watch it all resulting in bent rounds 90% of the time. I can easily drop a round in by hand and slam the bolt forward so I don't think the chamber is the problem. Seems like either the feed ramps or the barrel extension is the problem. I'm sending a pic to Aero tomorrow then talking to AIM about possible returning the barrel if they'll take it back. I may just have to stick with Aero parts. Open to suggestions. I sent AIM these pics also since I bought the barrel through them. It might be painful but perhaps the barrel will have to be replaced with an Aero since the whole build is pretty much Aero parts. I don't think I want to start dremel cutting the upper. Ugh!!! thanks all!

You will likely avoid the issues im having and probably have a smooth build process as long as you stick to one manuf. Take your time. Enjoy. thanks

I'm in the middle of building one myself and I ran into problems trying to chamber a round. At the moment, I think the best advise i can give you is don't do what i did and think you can build one as easy as an ar-15. The parts are not standard like an ar-15 and twice the cost so it takes a lot more to get the to work together. If I had it over, I think I'd pick a single manufacturer for the barrel, upper receiver and bolt carrier group and go from there. I'm working on a Mega barrel, Aero precision upper receiver and a AIM surplus bcg and I can't get a round to go into the chamber without bending it. Pretty damn frustrating after a lot of $. The lower receiver is easy to build as long as you use the same manuf for the receiver and parts kit. If you don't, you may have to alter some of the parts. For the upper receiver/barrel install you'll need a vise and a vise block or barrel tool so you can torque the parts on. When you get to that point im sure others will jump in and offer better advise than i can. I used 2 wood blocks LOL. Not very ideal but it worked. Good luck!

This is when I drop a round in by hand. There's a small scuff below the neck. And here is an attempt to charge with full spring action. Bent round. This was done with all factory 7.62 L2A2, Hornady sst 150 grain and Federal bthp 168 match.

Finished the build yesterday. I lubed it up with slip 2000 (bolt, charge handle, chamber, ramps ect) and tried to chamber a round out back and bent several rounds near the base of the bullet. I let the charge handle back all the way and let go, also tried doing it slowly to watch the round and see if it was hanging up anywhere but didn't notice anything. I used a few 308 rounds and also 7.62 with similar results and all 4 of my Magpul gen3 mags. Unfortunately I don't have other mag brands to test. The AIM bcg and Mega barrel passed the go/nogo headspace test. I have another AIM bcg on the way so I can test. I may order a different mag brand to test as well. I wonder if the Mega chamber is just very tight. Kinda disappointing after over $1.6k. The 2 successful chambers out of 10 attempts has the bcg lock in and the round extracted fine so I'm stumped at the moment. Any suggestions?

haha i did that already with AR15s. learned my lesson.

I may do that eventually. Thanks for the info. I guess I'll post my trigger guard for sale.

nice! thanks!

Interesting. How did you modify the mag? thanks

My first AR15 build did this and my gas block wasn't aligned properly. I ended up having to back it off the width of a dime. Do you have an adjustable block?

My first 308 build! Here’s my parts list. Some are on order. AeroP M5 upper/lower receiver AeroP LPK AeroP buffer kit (carbine) AeroP charge handle Magpul CTR + Enhanced .70” pad Magpul alum trigger guard Aimsurplus Nitride BCG Mega 16” barrel Syrac adj gas block + mid length gas tube Griffin compensator Midwest industries key mod 12” handguard DWilson BCG rebuild kit Vortex 30mm 3” offset scope mount Vortex Viper HS 2.5-10x scope Magpul 20rd mags Clymer Go/No-Go 308 gauges I’m interested to see the AIM BCG. I had one for my AR15 and it was great. Hopefully this one works well. I always keep a spare so I’m likely getting another BCG so I’m open to suggestions. I thought about getting a Fulton NiB or a Fulton chrome carrier + JP enhanced bolt. Not sure yet but I plan to put a lot of rounds through this gun so I definitely want a good bcg and a spare. I also want 1 x 5rd mag for hunting. Any suggestions for a quality/reliable one? I’ll post pictures when I get stuff shipped. In particular the AIM bcg. thanks!

By the way, this forum is great. So far I haven't had to ask a single question regarding my first build. I've found everything I need so far.

Gulf Shores. Unfortunately an hour from the nearest gun range.

Thanks everyone. Looking forward to the 308 AR world Yoda is.

Hi all, new to the forum and starting a 308 AR build. Looking forward to learning from everyone. thanks!