I am in the process of building my First Ar 15 that I will own. My Anderson stripped lower has gone together perfectly so far. The PSA lower parts kit is great too. I have a BCM Gunfighter Stock Mod 0 on the way from Amazon. I plan on going the MK 18 route (Form 1 one it). I have one little question/problem.

I bought this Buffer Tube Kit off Amazon and it is Mil-Spec. It fits my friends Magpul stock really tight and there is almost no wobble. Anyways, It has this weird notch where the buffer detent sticks up into. When I screwed the buffer tube in to where the buffer detent was perfectly in the half notch circle, my friends upper receiver would not go in because it was hitting the buffer tube. However, when we unscrewed it one turn, the buffer detent was still being captured and his upper fit fine. Should I file it down, or just leave it alone? As long as the detend is captured by the tube, it should be fine, right?
https://s183.photobucket.com/user/BusterBunker/media/IMG_20160207_234825.jpg.html?filters[user]=46366287&filters[recent]=1&sort=1&o=0
https://s183.photobucket.com/user/BusterBunker/media/IMG_20160207_234815.jpg.html?filters[user]=46366287&filters[recent]=1&sort=1&o=2
https://s183.photobucket.com/user/BusterBunker/media/IMG_20160207_234948.jpg.html?filters[user]=46366287&filters[recent]=1&sort=1&o=1

Your pics are not showing!

Leave it alone!

As a noob, welcome & check this link for helpful info!

Yeah pics no worky. But if you got it to close and the detent is still holding the buffer you are doing it right.

I added the Pictures to photobucket. Wasn't sure if people could see them through Google. The links work.

The third photo shows the buffer tube and the circle half notch.

As long as the detent is captured, you're good to go.

that's what the lock nut is for. the tube can be held in place any distance. as others said as long as the detent is held in place.

you used the wrong codes for your photos.. use the "direct" link and the {IMG} tags..

Hey, thanks for changing that for me:)