AR 300Blackout feed ramp fix

[Friar_Tuck]

In my search for a cast bullet that shot well and cycled well in my 8.5” SBR in 300 Blackout, I have really enjoyed this mold.
http://noebulletmolds.com/NV/product...vaqov3gcc7jog6
That bullet, over 13 grains of Lil-Gun is a great shooter for me.
The only drawback is that chambering the first round was often a bit finicky.
It would often hang up on the ramps.
Then I noticed when taking an unfired round out of the chamber that they had 2 gouges in the bullet from the ramps as seen below on the left bullet.

When I looked at the ramps it was obvious from the marks on the corners where the bullets were hanging.

As much as the thought of going after my nice set up with a Dremel tool made me nervous, the thought of marred bullets and the first round hanging up often was worse.
I went in with a small round end sanding drum and beveled the corners a bit, leaving the bottoms and chamber end of the ramps as was.


I reassembled it and it feeds smooth as butter now!
Now that I know the profile is as I want it, I may take it down once more just to give it a good polishing.
As nervous as I was to tackle the job, it was very simple, and turned out great.
Thanks to all of you on here that share your knowledge, so we can tackle things we would have never thought of!
Jim

[Hamish]

Outstanding post! Nothing so frustrating as dark out of focus pics.

[Artful]

You done real good.

[mto7464]

You read mine mind. I just came here to ask about the same issue with my BO. I will follow this post to see how things go.
How does it look installed

[Friar_Tuck]

Feeds like butter now, and no marks on the boolits!

[Gunnut 45/454]

Friar Tuck
I would have went for rounding the edges vs that much metal removal. So other then no dings on the bullets did accuracy improve any? Cause I would think those little dings would have no bearing on accuracy.

[Friar_Tuck]

Friar Tuck
I would have went for rounding the edges vs that much metal removal. So other then no dings on the bullets did accuracy improve any? Cause I would think those little dings would have no bearing on accuracy.

I use this at close range, so no accuracy issues before or after. The marks would not have affected the short range shooting I am doing, but just looked bad to me. The main improvement is just being able to let the bolt slam home and know that a round has been fed into the chamber, not hung up.

[destrux]

I was having those same marks but changing magazine type fixed it for me. The rounds weren't stacking right in the mag and were feeding funny.