Issue:  Failure to feed

Background: 16" White Oak bbl purchased with matching bolt.  Load is a moderate load of IMR4198 under 120 grain Nosler BT's or an 85 gr Horn HP, CCI 400 primer.  Cases eject at a nice 3-4 o'clock position 5' from the bench in a pile. This was a bbl break-in day with only a few rounds in the magazine between cleaning (3-5).  Magazines are 10 round or 20 ASC with blue follower marked 6.5 and Stoner magazines with blue follower marked 6.5.

The problem: The 120gr Noslet BT round lifts into the locking lugs (M-4 cuts) but only feed 3/4's of the way and then they stick.  I looked for brass transfers on the lugs and feed ramp - some brass scrapings on the center lug between the two M-4 feed ramps but nothing very obvious on the brass themselves.  With the 85 gr Horn HP's the found runs right into the face of the upper receiver and will not feed at all.

My attempt at problem solving: I pulled a lower from another AR and moved magazines around to mix it up...no change.  When I got home I compared the 6.5G mags to my 7.62x39 mags, inserted rounds in both and the angle seems the same on both (I did not have the 7.62x39 mags with me at the range).  I'll be reloading and playing with some dummy rounds tonight in various mags.

My first thoughts: I'm guessing that this is a mag / follower issue.  Are there some tried and true modifications to the mags / followers that may start the lift from the mag and into the chamber a bit earlier?  How about polishing and reducing the angle of the feed ramps?  Is this a common problem with the 6.5G (it is my first G).

Thank you in advance, Bill in OR

Sounds like you might have a couple things going on.  My experience with ASC  has led me to take the magazine apart and clean the interior of the mag body.  Inspect the follower and remove any excess plastic from the follower.  Try moving the follower in the mag and make sure it does not hang up.   My ASC mags had a gummy substance on the inside of the mag body.  Cleaning my mags seemed to help.  I also load my new 6.5 Grendel mags to capacity and let them set loaded.

Leaving the mags loaded or manually loading and unloading seems to help the mags wear in quicker.   The ten round ASC and C Products mags I own are marketed as being ten round but only hold nine rounds.  ASC and CP count the chambered round in the capacity so my five round mag only hold four rounds.  The ASC mags that are the size of a twenty round 223/5.56 hold fourteen rounds and are probably some of the more trouble prone 6.5 Grendel magazines.  Alexander Arms never sold the 14/15 round mag and requested CP use a curved body which they didn’t.  If you look at the 17 round E-Lander mag the body has a slight curvature similar to a 30 round 223/5.56 mag.  The full size 6.5 Grendel mags by ASC, CP and E-Lander hold 24 rounds.

One way to isolate a mag problem is to load one round in the mag, load and fire, bolt should lock back.  If the bolt doesn’t lock back on the bolt catch you may have under powered ammo or insufficient gas.   If the rifle functions with one round then load two rounds.  If the rifle functions with two rounds then try three rounds.  Some times a mag will fail to feed from one side (even or odd # side).   It is a common problem for ASC mags to need the feed lips tweaked to obtain proper feeding.

If I were you I’d probably try to test the rifle with factory Hornady ammo as it usually will feed reliably.   The 85 grain Sierra varmint bullets are very short and blunt and need a good magazine to feed.

If the rifle feeds reliably with just a few rounds then fails to feed the mag spring may not be raising the top cartridge fast enough for the bolt to feed the top round.   If the feed lips are not bent high enough the bolt has a tendency the push the cartridge forward into the top edge of the mag body and into the mag well instead of up into the feed ramp.  I use needle nose pliers to slightly bend the feed lips to allow the nose of the top cartridge to set a little nose up while in the mag.   Many times if the top round lays completely flat in the mag you encounter feeding issues.   Some mags only fail to feed from one side.  I had a 24 round ASC mag which failed to feed from the non ejection port side (left).   I compared the left side feed lip to the right side lip.  The left feed lip was lower.  I used needle nose pliers to bend the feed lip on the left side to match the right side.   The mag I adjusted the feed lip on hass not failed to feed since adjusting the feed lip.

If you decide to tweak the feed lips only adjust one mag to see if you can get it to function.   The issue not feeding the 85 grain SV makes it sound like the feed lips might need tweaked.  The AR Stoner mags are rebranded ASC mags so basically your dealing with the same brand of magazine.   With a new build I always use a lot of CLP on the bolt, carrier, charging handle.   I try to test new builds with factory ammo with the method described.  In my experience new 6.5 Grendel mags come with very strong springs and it takes a while for the mags to wear in.   Using untested reloads just makes it more difficult to diagnose the problem should you encounter any type of failure.   Sounds like this might be your first 6.5 Grendel.   I just finished my fourth 6.5 Grendel AR-15 today and plan on testing it tomorrow with factory Hornady ELD-M black.  If all goes well maybe a few reloads.

The stoner mags are garbage, well they did feed steel case fine but nothing brass. The follower and feed lips are wrong.

I am using ASC 10rd(really 9rd) mags in my Grendel and have had 100% function. Do your ASC mags have Alexander Arms plates on the bottom?

You might consider the e lander mags from Alexander. My 4 round clip had feed problems but it broke in and runs fine now. It also says 4 rounds but holds with one chambered. I cut 1/4 inch of spring off the bottom and it now holds 4 rounds and runs well. Time will tell if that was a good plan. The e landers I have are steel and dry lubed with white no tip followers.

This is not the case, at least for the ASC mags that I personally own.

I recently purchased some ASC 10 round magazines, and some would easily hold 10, others would practically sieze up at 9. On one magazine, it stopped at 9, but as I was trying to load the 10th round there was a "pop", and suddenly the excess tension was gone and the 10th round loaded just fine.

I took the floor plate off another mag that stopped at 9, brushed out the mag body, and then reassembled it. No problems holding 10 after reassembly.

I personally think that either something is catching near the bottom of the magazine, such as flashing on the follower, or perhaps a small chunk of coating on the mag body, or that perhaps the spring is binding up somehow.  Whatever it is, once it clears the obstruction or the spring snaps into the correct orientation, it's no longer a problem.

All of my ASC mags hold the appropriate number of rounds, whether it be 5, 10, 15, or 25.

< Comment Removed - F > The Grendel has been around long enough that IMO “tweaking” mags should not be necessary.  If they’re not designed to spec or the manufacturing process won’t hold ‘em to spec...shop elsewhere...

Folks offering anecdotal experiences/fixes are just that.  No reason for trial & error at this point IMO...it works or it’s shitty luck of the draw.

When you say "shop elsewhere", where exactly did you have in mind? There are very few manufacturers for Grendel magazines, so the options are rather limited.

I understand the concern about "tweaking" magazines, and I'm not much for trying to modify or adjust feed lips, personally.

However, I do feel that disassembly, cleaning, and reassembly of a magazine would fall under "maintenance", not "tweaking". Just as most people will clean, lubricate, and inspect a new firearm, it makes sense to do the same with new magazines.

At present the go-to mags are E-Lander.  The Grendel and magazine design is interesting.

When did White Oak start making Grendel barrel's?

Wow!  Your post ought to be a sticky.  Great info in an easy to  read format....thank you.  FYI: the bolt stayed locked to the rear on every shot.  I'm going to pull every mag apart and give them a nice looking over.  I'll buy another mag from some other manufacturer also just to see if they feed.  The weapon shoots fine (right at MOA on the first go-around) so once I get the feeding under control I think I'll like it.  Thanks again, Bill in OR

I tried using simple P-Mags.  They feed if loaded with 8 rounds or less in my rifle.  I know they are not the "perfect" but seem work okay for light range work or even hunting where you don't need to feed a mag full at a time.

I have a BCA 16 inch upper with what they call 300BO upper cuts, whatever that means.

I just finished my exam of both the  ASC and Stoner mags since arriving home from the range yesterday.  When I slowly feed the round into the chamber I noticed the the angle was a bit to shallow to rise the round up from the mag's and into the feed ramps.  So next I removed the mags, filled them with rounds and tried pushing them out one by one by hand.  What I observed was kind of what I expected, with a twist.  As the rounds moved forward some hesitated on the small edge of the polymer tip where it meets the copper, it was such a small lip it surprised me.  Then as the round moved forward the sharp edge of the inside mag edge stopped / slowed the forward momentum when the front edge of the case mouth contacted it.

So, it looks like some Dremel tool work on the front of the mag to lower the front face and MAYBE using needle nose pliers to slightly expand the lips to give the rounds in the mag a bit more angle may get this weapon back on line.

I'll be getting to the range Sunday or Monday....more to follow.

Bill in OR

You must know that no one appreciates your input. Maybe you should just be quite and listen (read)...could be that you just might learn something.  Just a suggestion.

Bill in OR

You think mag manufactures who either build from a flawed design or can’t hold a given QC level DON’T need to pull their heads out?  Info on how to mitigate flawed products is great but you shouldn’t have to...JMO.

< How hard is it to say ON TOPIC? - F >

< How hard is it to say ON TOPIC? - F >

We all need to be a bit more sensitive, lol but Funnelcake does have a point if taken in proper context.   My ASC 10 round mag follower seemed to have been shortened with a hacksaw and the cut not even clean up.  Need to check the couple other 10 rounders I have still bagged.

5rd on top/ 10 rd on bottom

Yeah, my bad...I was referring to mag manufacturers, not the OP or folks trying to help.  I can see how my initial reply could've been taken out of context.

I am not condoning buying ASC mags but when I bought my first 6.5 Grendel in 2010 C Products mags were the only 6.5 Grendel mag manufacturer.  C Products got into some financial issue and was taken over by ASC.   The last ASC mags I bought were several years ago before C Products Defense started producing 6.5 Grendel mags.

The CPD Gen 3 6.5 Grendel mags get pretty good reviews but if you follow the 6.5 Grendel you’ll see where all 6.5 Grendel mags have a few lemons slip through.   I have bought several E-Lander mags and they have been gtg.   One thing about 6.5 Grendel mags and specifically the E-Lander mags are very stiff/strong springs when new.   I bought four 17 round, one 24 round and one 10 round E-Lander mag from Brownell’s before Christmas.  Upon receipt I fully loaded the mags.   I have physically unloaded the mags a couple of times and they are just not now starting to wear in even though being loaded to capicity since receipt.   I took a newly assembled 6.5 Grendel out today for it’s first test.  I loaded a few cartridges in the ten round and two 17 round E-L mags and the rifle functioned 100 % in the 15 degree temperature.

Some complaints about the E-Lander mags is they are heavy, rattle when fully loaded and a few reports of bad welds.  Alexander Arms has supposedly replaced any defective mags sold by them.   I know if I have a problem with my E-Lander mags Brownell’s will take care of me.  My most recent mags from Brownell’s are marked E-Lander.  My previous mags purchased from AA were marked E-Lander and also had the AA logo.  I suspect AA had a marketing agreement with E-Lander where AA was the sole supplier of the 6.5 Grendel mags for at least a year.  AA supposedly consulted with E-Lander on the design of the E-L 6.5 Grendel mags.  E-Lander mags are now being sold by AA, Aim Surplus, JP, JSE Surplus, Larue, Brownell’s and probably other vendors.

The capacity of my ASC mags and CP mags was the way they were delivered.  I know some people have modified the followers or spring to accept an additional round.  From my experience ASC and CP didn’t keep very tight tolerances during manufacture.   My recommendation if anyone is going to buy 6.5 Grendel mags is to buy from a vendor with good customer service in the event you get a lemon.   There was a rumor another manufacture was going to release a 6.5 Grendel mag.  Maybe we’ll here somthing at this years SHOT show, maybe it’s just an internet rumor, time will tell.

Bill, there were some users of early CPD and ASC 7.62x39 where they lowered the front edge of the mag.  As you observed the edge of the cartridge case can catch on the top edge of the mag during feeding.   This has got to add drag and slow the momentum of the BCG in feeding a cartridge.  This is bad but you add a new full mag in a new build and it’s not surprising people experience failure to feed.  In my experience bending the feed lips up a little to allow the cartridge to release a little sooner solves most of the feeding issues.  I think just lowering the front edge of the mag might still not allow short blunt bullets like the 85 grain Sierra Varmint to feed.   I never modified the front of my mag so I can’t say for sure.   I haven’t had any trouble feeding 85 grain SV 6.5 Grendel cartridges in my good mags.

The ASC and CP mags are supposed to be stainless steel bodies but the tensile strength of the lips don’t seem to be much stronger than aluminum 5.56/223 mags.  I don’t know if the mag lips are getting bent during shipping but I suspect most of the problem is lack of QC during manufacture of ACS and CP mags.  I can’t comment on CPD mags as I have no experience with them.

We had an ASC 25-rd. mag last week that would not fit in the mag well on a new build using an Aero lower.  Just for the heck of it...started sanding/filing...the amount of metal that had to be removed was impressive...c’mon!!  And yeah...that follower in the pic above looks familiar...

The E-Landers aren’t perfect either but I haven’t yet had one fail to feed properly much less not fit in the friggen rifle...

FIXED, FIXED....I'm the OP.  In the way of a little background, back in the day I was a Company Armorer and maintained well over 100+ AR's.  So I've seen and repaired quite a few failures in AR's over the years.  Everything told me that this was a magazine issue.  You know the drill - if it walks like a duck, quacks like a duck and looks like a duck...it's a duck right?  Well, I spent an hour playing with mags; taking them apart, filing burrs, inserting them into the mag well, slow feeding and bolt slamming, trying .223 and 7.62x39 mags and still there was a failure to feed and the rounds would travel 3/4's of the way into the chamber and just stop.  I thought that this was progress because before they were hanging up on the front of the mag with almost every shot.  I tried re-positioning and feeding rounds only out of the left side, then the right side of the mag.

The problem was that the ejector plunger was a few thousandth too long.  It extended past the front of the bolt face, barely noticeable unless you were looking for it - but of course I was not.  As the round would ride up and out of the magazine and start slipping into the chamber the plunger would catch the base of the bullet and not let it slip into the bolt face and seat.  I couldn't find my Dremel so 10 minutes with a file (those plungers are hard!) I shortened it just enough to be recessed just below the bolt face.

Of all the scores of AR's I've handled I've never seen this, so I was so fixed on all the other issues I was familiar with that I got tunnel vision. For me, lesson learned.  I guess the good news is that my 6 mags have all been taken apart, cleaned and the followers cleaned of any burrs and debris.   I have not done any live fire yet (that happens Sunday) but feeding rounds out of each mag allows the bullets to enter the chamber.  The 85 gr HP's are still a problem but I'm happy with the 120 Gr Nosler BT's anyway and I doubt that the coyotes will notice the difference.

Thank you all, I learned a LOT.
Bill in OR

Thanks for the update Bill!

That makes sense as I’ve read of this occurring before but is normally was resolved by putting a radius on the square edge of the ejector.   Never heard of an ejector pin being to long.   The radiused ejector edge permits the rim of the case to slide onto the breach face of the bolt during feeding.   I assume this is an issue because of the larger diameter case head compared to the 223/5.56.   I really never encountered this failure on a 223/5.56 AR-15.

I’ve read where guys will clip a couple coils on the ejector spring to reduce the velocity on their ejected brass.  Pretty hard to trouble shoot on the other side of your keyboard.

I don’t know about you but I get a lot of satisfaction from fixing guns.  Some are real head scratchers and some times I end up having to go to a gunsmith Friend.   Together we’ve been able to solve a lot of troublesome guns.

Thanks again for posting your problem/results, these post really help other forum members!

AR Ejector Mod
I'll leave this for some light reading.

Great article, that is a mirror image of what I ended up doing.

It is funny, but, after all these years I almost look forward to having an "issue" with one of my firearms that needs / requires some brain cell burning to overcome.  I'm not a gunsmith by ant stretch of the imagination but I do seem to have the ability to reason out and find solutions to simple problems that crop up.  Because I'm a bit stubborn (according to my spouse) I don't often give up.  Someone else with more experience might have found this little issue a lot faster.  Anyway....thanks for all the help, it was much appreciated.

Bill in OR

Thinking back about your description where the cartridge stopped partially in the chamber needs to be a red flag to check the ejector.   On some failure to feed malfunction the bolt hit the cartridge and jams it on the feed ramp only parially in the chamber.   Sometimes the cartridge is stood almost straight up if there is room for the cartridge to be pinched down into the magwell.   On rifles with insufficient gas or to much drag on the bolt the carrier doesn’t move far enough to the rear.   The bolt will actually hit the cartridge shoulder and gouge the case.

Thanks again for posting Bill!

I had a similar problem last year with a 6.5 Grendel build using a PF barrel and bolt.  Turned out the extractor was too tight, not letting the extractor snap over the case rim while feeding.  It didn't happen all the time, just often enough to be a PITA.

I removed an o-ring off the extractor spring.  It ran great after that.

I'm the OP.  Range / test day today and my new Grendel ran perfect.  ASC, Stoner and some other mag (5rd, 10rd and a 20?) that a friend converted all feed like a champ.  It was the ejector protrusion that was causing me and the gun grief.  As a side note, I was surprised at the consistency of  the POI's were with 4 powder combinations.  IMR4198, WW748, Varget, AA2520 all had a POI within .5" of each other, and the groups were much better than I could have expected from a 1.5-4X scope @ 100yds.  Three shot groups ran from just under .75 to just over 1"; all with the 120 Nosler BT, all minute of coyote.  I have several other variant AR's: 6mmTCU, 7.62x39mm and .308....this little Grendel just might move to the top of my "like" list.

Thanks again for the assist,

Bill in OR

Great to hear you got your 6.5 Grendel sorted out and thanks for the updates.   I to have been  pleasantly surprised how close different bullet weights and powder charges hit close to point of aim at 100 yards.  As expected shooting at extended range the different bullets will hit further from POA but for quick load developement it kind of simplifies the task.

The 6.5 Grendel cartridge has it's own unique characteristics but is a very versatile and enjoyable cartridge to use.

Is White Oak starting to do Grendel barrels or was it a custom barrel?

I'm guessing that they are, maybe on a limited basis?.  In a previous post I outlined how I came into the bbl.  It was a gift to me but the receipt indicated that it was from White Oak and it had a matching bolt.  The cost was $350 or so for the pair (I've tossed the receipt).

Sorry I don't have more.

Bill in OR