ar10-6.5 creedmoor feed problems

[usmcranger]

hello all, i started out with a diamond back ( dpms), ar-10 20-inch barrel and went to (dpms) 24-inch Brownell's barrel , i reloaded some Hornaday 135g a-tips at Sami specs and it jams into the face behind the feed ramps, the round goes Straight threw the feed ramps, so know im not sure what to do??? the Winchester 125 g open tip rds works fine, the Winchester 125 g extreme point jams up just like the 135 g a-tips do, are they just to long or is it the angle of the feed ramps?? here are some picks of were the rds are hitting and the are 2 pictures of old barrel with the wide gap at bottom and then 2 pictures of the new barrel , any help would be appreciated.

 

[Evintos]

Some potential problems.

1. Feed cone angle of the chamber is not wide enough. Return to manufacturer for warranty.
2. Feed ramp angle of the barrel extension is not steep enough. Return to manufacturer for warranty.
3. Magazine follower feed angle does not allow for a better feed angle. Try different magazines that presents the bullet tip at a more upward angle.
4. Magazine catch is positioning your magazine too low. This is a tough one if this is the result of a tolerance stack issue or out of spec lower.
5. The secant ogive bullet geometry of the Hornady ATIP and Winchester Extreme Point does not play well with the feed ramp angle of the Brownells barrel.

In general you normally see this when the manufacturer utilizes the same feed cone and barrel extension ramp specs (angle, width, dimensions) as a 308 barrel.

 

[newguy2k3v2]

That extension looks like it’s cut for some type of big bore cartridge like a 45 raptor or something. There’s almost no center lug. On a 6.5 you’d want it a bit narrower so the bullet rides up the lugs to line it up with the chamber. With what you have they’re skidding up the bottom and predictably jamming into the back of the barrel.

Send it back to whoever made it. It’s junk unless they can get another extension to time and headspace perfectly somehow.

 

[FALex]

I know it is a huge PITA to get pics inside of the action, but any chance you can take some without a mag inserted (where extension meets receiver, right where your rounds would be if you were to insert a mag)? Your last picture in the series almost shows that area, and from what I can see, it does appear that there may be ramps in the receiver. It would be nice to see if the receiver has any feed ramps machined into it (typically known as "M4 feed ramps").

Interesting little tid bit of history: M4 feed ramps were designed because the military discovered M855, being more pointed and having higher pressures, was causing feeding problems in some of their rifles. I said that to simply imply that this may be an issue for you as well.

 

[bfoosh006]

That extension looks like it’s cut for some type of big bore cartridge like a 45 raptor or something. There’s almost no center lug. On a 6.5 you’d want it a bit narrower so the bullet rides up the lugs to line it up with the chamber. With what you have they’re skidding up the bottom and predictably jamming into the back of the barrel.

Send it back to whoever made it. It’s junk unless they can get another extension to time and headspace perfectly somehow.

This... I can't say I have every seen the bottom lug removed almost completely in ANY of my DPMS pattern 308's or 6.5CM's barrels.

And the feed ramps that would have been there, are "gone" ... note the use of the word ramps.

I can't help but wonder if "Brownells" installed the wrong barrel receiver extension.

 

[n2ishun]

Yup.
Extension is fuxored.

 

[2aBaC̶a̶]

i cuncur. feed ramp should be two not one.

 

[usmcranger]

i cuncur. feed ramp should be two not one.

that barrel is from diamond back rifles that has no lug in middle, thats why i went to the brownells barrel

 

[usmcranger]

I know it is a huge PITA to get pics inside of the action, but any chance you can take some without a mag inserted (where extension meets receiver, right where your rounds would be if you were to insert a mag)? Your last picture in the series almost shows that area, and from what I can see, it does appear that there may be ramps in the receiver. It would be nice to see if the receiver has any feed ramps machined into it (typically known as "M4 feed ramps").

Interesting little tid bit of history: M4 feed ramps were designed because the military discovered M855, being more pointed and having higher pressures, was causing feeding problems in some of their rifles. I said that to simply imply that this may be an issue for you as well.

theres no cut outs at bottom were feed ramp would start in the upper reciever

 

[usmcranger]

Some potential problems.

1. Feed cone angle of the chamber is not wide enough. Return to manufacturer for warranty.
2. Feed ramp angle of the barrel extension is not steep enough. Return to manufacturer for warranty.
3. Magazine follower feed angle does not allow for a better feed angle. Try different magazines that presents the bullet tip at a more upward angle.
4. Magazine catch is positioning your magazine too low. This is a tough one if this is the result of a tolerance stack issue or out of spec lower.
5. The secant ogive bullet geometry of the Hornady ATIP and Winchester Extreme Point does not play well with the feed ramp angle of the Brownells barrel.

In general you normally see this when the manufacturer utilizes the same feed cone and barrel extension ramp specs (angle, width, dimensions) as a 308 barrel.

ive contacted brownells, and they told me to get ahold of faxon sense they make the brownells barrels, and no word back from faxon yet?.

 

[Evintos]

ive contacted brownells, and they told me to get ahold of faxon sense they make the brownells barrels, and no word back from faxon yet?.

https://www.instagram.com/faxonfirearms/

Try contacting them through Instagram. Messages through social media tend to be more effective these days with many companies versus email or phone calls.

 

[2aBaC̶a̶]

looks like a 458 Socom feed ramp. maybe somone got the barrel extension wrong?

 

[padom]

A 135 A-Tip is a LONG pointy bullet...just like a 140 Hybrid that also doesn't feed reliably in a 6.5cm gasser.... stick with correct for gun bullets like 130 Hybrid, 130 ELD, 123 Scenar, 130smk....140 eld do feed reliably in my 6.5cm gassers u like 140 hybrids...

 

[usmcranger]

A 135 A-Tip is a LONG pointy bullet...just like a 140 Hybrid that also doesn't feed reliably in a 6.5cm gasser.... stick with correct for gun bullets like 130 Hybrid, 130 ELD, 123 Scenar, 130smk....140 eld do feed reliably in my 6.5cm gassers u like 140 hybrids...

the reason i want to use the a tip is for long range shooting comps., what would be the best to use??

 

[usmcranger]

the reason i want to use the a tip is for long range shooting comps., what would be the best to use??

6.5mm .264 Diameter 140 Grain Boat Tail Hollow Point> 6.5mm .264 Diameter 140 Grain ELD-Match>6.5mm .264 Diameter 140 Grain Match Burner Lead Core Boat Tail will these ones work you think??/

 

[FALex]

the reason i want to use the a tip is for long range shooting comps., what would be the best to use??

I run a 139gr Scenar in my JP. However, I just purchased a box of 120 ELD M's to try out. The Scenars are very easy to load for; they are very forgiving. However, the 120's might even be better if I can get them above 2800 (2850 would be optimal).

I would love to see a good side-by-side comparison of the A-Tips against a traditional OTM, or even, an ELD-M. I'm sure Hornady didn't spend a bunch of R&D cash on them just to say they make an aluminum-tipped projectile, but I've been wrong once before.

 

[padom]

6.5mm .264 Diameter 140 Grain Boat Tail Hollow Point> 6.5mm .264 Diameter 140 Grain ELD-Match>6.5mm .264 Diameter 140 Grain Match Burner Lead Core Boat Tail will these ones work you think??/

Those should work they look like 140 eld...

I run Berger 130 OTM and 123 Scenars out of a 22" Bartlein +2 gas....lights out

 

[Evintos]

https://www.snipershide.com/shooting/threads/new-hornady-a-tip-bullets.6939959/post-7706920

The below pic isn't specifically 6.5cm but I think it best shows the bullet profile differences between an A-Tip versus an ELD
https://www.shootingtimes.com/editorial/hornady-a-tip-bullet-review/372700

---------------------------
Edited to add
https://www.shootingtimes.com/editorial/65-prc-versus-300-prc/330107
from left: Barnes 127-gr. LRX, Sierra 130-gr. GameChanger, Swift 130-gr. Scirocco II, Hornady 140-gr. ELD-M, Sierra 142-gr. MatchKing, Nosler 142-gr. AccuBond Long Range, Hornady 143-gr. ELD-X, Hornady 147-gr. ELD-M.

 

[usmcranger]

Those should work they look like 140 eld...

I run Berger 130 OTM and 123 Scenars out of a 22" Bartlein +2 gas....lights out

i just orderd these today >>6.5mm .264 Diameter 140 Grain Boat Tail Hollow Point Match

 

[chase723]

A 135 A-Tip is a LONG pointy bullet...just like a 140 Hybrid that also doesn't feed reliably in a 6.5cm gasser.... stick with correct for gun bullets like 130 Hybrid, 130 ELD, 123 Scenar, 130smk....140 eld do feed reliably in my 6.5cm gassers u like 140 hybrids...

This^^^

When I built mine it would not feed the 140 hybrids at all. It would do exactly as the pictures you posted. Super frustrating. However, it absolutely loves the 130 Sierra Game Changers. A shorter bullet with a polymer tip was the ticket to getting it to guide rounds into the chamber. Shoots them incredibly well…aside from being a little heavy it honestly makes me wonder why I even use a bolt gun.

 

[usmcranger]

This^^^

When I built mine it would not feed the 140 hybrids at all. It would do exactly as the pictures you posted. Super frustrating. However, it absolutely loves the 130 Sierra Game Changers. A shorter bullet with a polymer tip was the ticket to getting it to guide rounds into the chamber. Shoots them incredibly well…aside from being a little heavy it honestly makes me wonder why I even use a bolt gun.

This^^^

When I built mine it would not feed the 140 hybrids at all. It would do exactly as the pictures you posted. Super frustrating. However, it absolutely loves the 130 Sierra Game Changers. A shorter bullet with a polymer tip was the ticket to getting it to guide rounds into the chamber. Shoots them incredibly well…aside from being a little heavy it honestly makes me wonder why I even use a bolt gun.

well i just orderd these ones> 6.5mm .264 Diameter 140 Grain Boat Tail Hollow Point Match , going to try these sense there just like the 125 grain open tip Winchesters shoot good threw my rifle

 

[chase723]

You’re going to need to seat them deep. What powder are you using? May need to use something in the Varget burn rate instead of H4350 burn rate in order to get a max charge in and seat them deep enough to avoid the problem you’re currently having. You will be a little slower but accuracy is often excellent. The goal though, first and foremost, in a semi auto rifle is that it functions as a semi auto without failures to feed.

 

[usmcranger]

You’re going to need to seat them deep. What powder are you using? May need to use something in the Varget burn rate instead of H4350 burn rate in order to get a max charge in and seat them deep enough to avoid the problem you’re currently having. You will be a little slower but accuracy is often excellent. The goal though, first and foremost, in a semi auto rifle is that it functions as a semi auto without failures to feed.

im going with the stabill 6.5 powder and switching to the 6.5mm .264 Diameter 140 Grain Boat Tail Hollow Point Match

 

[padom]

You’re going to need to seat them deep. What powder are you using? May need to use something in the Varget burn rate instead of H4350 burn rate in order to get a max charge in and seat them deep enough to avoid the problem you’re currently having. You will be a little slower but accuracy is often excellent. The goal though, first and foremost, in a semi auto rifle is that it functions as a semi auto without failures to feed.

Why do you need to seat them deep? I've shot 1000's of these along with 140 ELD and never had to seat them deep....2.83" which was 0.02 off lands..... these aren't like 140 hybrids and 135 A-Tips....they feed no problem in all the 6.5cm gassers I've built...

 

[usmcranger]

Why do you need to seat them deep? I've shot 1000's of these along with 140 ELD and never had to seat them deep....2.83" which was 0.02 off lands..... these aren't like 140 hybrids and 135 A-Tips....they feed no problem in all the 6.5cm gassers I've built...

the hornaday 135 a tips go straight in threw the ramps on my barrel and hit just below the chamber on the face ,, the barrel is from brownells/faxon barrel 24 inch, so im switching to the 6.5mm .264 Diameter 140 Grain Boat Tail Hollow Point Match to see how they work, will let you know when i get some loaded up. ive tried to get ahold of faxon but nothing yet?? i even went to there other page and no response back yet.

 

[usmcranger]

You’re going to need to seat them deep. What powder are you using? May need to use something in the Varget burn rate instead of H4350 burn rate in order to get a max charge in and seat them deep enough to avoid the problem you’re currently having. You will be a little slower but accuracy is often excellent. The goal though, first and foremost, in a semi auto rifle is that it functions as a semi auto without failures to feed.

i am, going to use these 6.5mm .264 Diameter 140 Grain Boat Tail Hollow Point Match with the 6.5 staball powder and either a federal #210 large rifle primer or a 250# magnum primer ??