Feed ramps on ar-10 barrel

[pldawg]

I have an aero upper and lower with a drop in barrel from a well respected barrel company but the feed ramps do not guide the bullet into the chamber. I have taken this gun to two local gunsmiths and sent the rifle to the barrel maker. The barrel company did add a bevel to the face of the barrel but the bullet tip still smashes into the face of the barrel and the feed ramps barely guide the bullet at all.

barrel is chambered in a 6.5 creedmoor and I have tried 143 eld-x and 140 hybrid bullets.

Any recommendations on a gunsmith I could send the barrel to for changing of the feed ramps?

the pictures attached are before the barrel company “chamfered” the chamber entry but the bullet still impacts the face of the barrel without much of any guiding from the feed ramps.

or do I just have to chuck this up to a lost cause and buy a different barrel?

 

[gixxer822]

have you tried a different mag? different seating depth? with that bullet profile im not suprised.

 

[pldawg]

I have tried different mags, someone suggested a metal mag so I could tweak the feed lips but from looking at it, it would have to be tweaked a lot to tilt it up and the feed ramps would not engage at all at that point.

I just tried a 127 barnes lrx at 2.75 coal and that did better and didn't deform the tip on feeding now that the face of the barrel has a chamfer on it.

 

[db2000]

What did the 2 smiths and the barrel company have to say? “We give up”
It seems odd none of them could get it to feed. If that’s the case I’d move on and part it out. Invest in one that’s known to work. Just my $0.02

 

[charnicus]

What are the different mags you’ve tried out? It kinda looks like an OAL problem to me. I didn’t see you mention the length of the 140 and 143 loads. Personally a 140 hybrid isn’t one I’d choose for a semi. Other than factory, no experience loading with the 143Eldx. In my 6.5 AR they didn’t perform well.

 

[pldawg]

both the 143 and 140 hybrid were loaded to COAL found in the manuals which is 2.800 for both.

the mags have all been magpul.

1st smith said he couldn't help
2nd smith said it probably wouldn't be cost effective to add metal to the feed ramps

Barrel maker chamfered the barrel face and sent it back.

What options should I look at for ones that are known to work? I honestly expected this one to work...but maybe these bullet profiles are just not appropriate for semi's?

Barrel shoots really well when single fed

 

[db2000]

both the 143 and 140 hybrid were loaded to COAL found in the manuals which is 2.800 for both.

the mags have all been magpul.

1st smith said he couldn't help
2nd smith said it probably wouldn't be cost effective to add metal to the feed ramps

Barrel maker chamfered the barrel face and sent it back.

What options should I look at for ones that are known to work? I honestly expected this one to work...but maybe these bullet profiles are just not appropriate for semi's?

Barrel shoots really well when single fed

Weird the barrel maker wouldn’t verify it working properly before returning it is all.

 

[sinister]

Ditch the plastic magazine, OR TRIM THE MAGAZINE LIP LENGTH / RELEASE POINT FOR THE CARTRIDGE TO COMPLETE THE FEED CYCLE.

From OP's photo the cartridges are hitting where they should, but aren't headed up the ramps because the mag lips are holding the cartridges for straight/forward feed.

If you go to a steel magazine, cycle the weapon to see when the feed lips release the ass-end of the cartridge.

 

[BCP]

You can trim the magazine lips or bend them upwards towards the front. I wonder if your mags are sitting too low in relation to the barrel.

 

[pldawg]

thanks, any preferred metal mag that I should get?