Newbie build question

[Jmbaker87]

I have a bear creek arms side charging upper with an 18” socom barrel 1/10 and I have a aero precision m5 stripped lower that was given to me on trade. I can’t seem to get it to fit properly is there anything I can do to get it to fit properly? It would fit but there is a loose fitting bolt on the upper that is keeping it from fitting properly This is my first ar10 308 build so any help or advice would be greatly appreciated. I’ve included pics of both the lower and upper for reference 

[shooterrex]

I would take some more metal off the flat of that plug till it fit. That plug is taking the place of the charging handle.

[Jmbaker87]

1 minute ago, shooterrex said:

I would take some more metal off the flat of that plug till it fit. That plug is taking the place of the charging handle.

Ok that’s kinda what I was thinking but wanted to double check. Does that plug need to be tight or just finger tight? This is my first side charging upper so im not to familiar with them. 

[shooterrex]

Finger tight should work. Take the plug out and see if the upper and lower fit ok. If they do the plug is the problem and can be modified so everything fits.

[Jmbaker87]

38 minutes ago, shooterrex said:

Finger tight should work. Take the plug out and see if the upper and lower fit ok. If they do the plug is the problem and can be modified so everything fits.

Thanks yea it fits fine the holes all line up fine you can still see light from in between the upper an lower but not a lot and it shouldn’t be an issue. I’ll just file the flat part of the plug down an see how it works. I got a 80% juggernaut lower that I’m milling out and I’ll see if it fits any better with my next build which will be the same style upper but with a 20 in barrel.