AR plastic / polymer mags for Grendel?

[Tedward]

Tried some of my Lancers, but they were a no go with more than three or four rounds. Spontaneous unloading with 10 plus rounds, the feed lips didn't have enough grip to hold the larger diameter case I suspect.

Did you change the follower to the blue ones? I haven't had the chance to trim the blue follower side glides or what ever there called but will try tomorrow. I need to use the milling machine to take off about a 1/16" off each side.

If you tried that already I won't mess with it. Also the spring might need changed, there might be to much tension. Or like you said, just the feed lips don't work. Need to take measurements there too.

Let me know so I don't try the same thing for nothing. Someone needs to make a Grendel top part for the Lancers if not. They seem much nicer than the P-mags. More firmer...

[Tedward]

I just spent an hour measuring a C-Products Grendel Mag and the Lancer .556 mag. Both have the same length feed lips and both tapper to the same measurement from front to rear. The curve on the feed lips are also the same buy checking with a case in both, the spacing is identical. I don't know what makes them any different from each other other than the follower.

[middle man]

I have two different generations of the Lancer mags...I'll double check again on both styles.

[bwaites]

I just spent an hour measuring a C-Products Grendel Mag and the Lancer .556 mag. Both have the same length feed lips and both tapper to the same measurement from front to rear. The curve on the feed lips are also the same buy checking with a case in both, the spacing is identical. I don't know what makes them any different from each other other than the follower.

The ribs. External dimensions have to be the same, they go in the same mag well. Its the inside that matters!

[middle man]

Checked a Lancer L5AWM this morning. After eight rounds the cases were too far off axis for the feed lips to keep them in place. As bwaites said, it's the rib in the mag body that contributes most to the problem. The rib protruding into the space for the cartridges in combination with the 5.56 dimension follower throws off the tip to rim alignment in standard 5.56 dimension magazines.



Past eight rounds the feed lips didn't engage enough of the rear of the case to hold and retain the cartridge. The alignment moves further and further off axis and only the middle of the case is really engaging the feed lip. PMags and similar clones have thicker bodies, as well as, polymer feed lips with less internal space for the increased diameter of the Grendel case.

Offsetting the step in the follower would change the manner in which the cases stack inside the magazine. Less rib protruding would also aid in changing the relationships of the cases as the stack inside as well.

[gastonglock21s]

Wilson Combat sells a Lancer L5AWM 20 and 30 round mag that is de-ribbed for use in their 7.62x40. They are both in stock ATM.

Curious to see how this turns out.

[Tedward]

Checked a Lancer L5AWM this morning. After eight rounds the cases were too far off axis for the feed lips to keep them in place. As bwaites said, it's the rib in the mag body that contributes most to the problem. The rib protruding into the space for the cartridges in combination with the 5.56 dimension follower throws off the tip to rim alignment in standard 5.56 dimension magazines.



Past eight rounds the feed lips didn't engage enough of the rear of the case to hold and retain the cartridge. The alignment moves further and further off axis and only the middle of the case is really engaging the feed lip. PMags and similar clones have thicker bodies, as well as, polymer feed lips with less internal space for the increased diameter of the Grendel case.

Offsetting the step in the follower would change the manner in which the cases stack inside the magazine. Less rib protruding would also aid in changing the relationships of the cases as the stack inside as well.

I hear what your saying but the mag lips from front to rear are the same exact measurement from outside of the mag to the inside edge of the lip. The gap in between the lips in front and rear are the same too. It might be how the lip is bent but not positive. Did you compare the same thing on the Grendel Mag to see if they sit on the center of the feed lip?

Did those have the different follower? That might be the answer if not.

[Tedward]

Wilson Combat sells a Lancer L5AWM 20 and 30 round mag that is de-ribbed for use in their 7.62x40. They are both in stock ATM.

Curious to see how this turns out.

Let me know if they work. Went to order 1 but $20 and $10 shipping is a little steep if it doesn't work. If I had a 7.62x40 I could use it for if it didn't work for the Grendel I would order 2 and then the $10 wouldn't be so bad and know it works for something.

[gastonglock21s]

Can you measure the max internal width and the internal width between ribs of the Lancer L5AWM where the large portion of the case is? The Wilson Combat modified mags would probably have to have the rear ribs modified as well because the 7.62x40 uses a .223 parent case.

[Tedward]

Checked a Lancer L5AWM this morning. After eight rounds the cases were too far off axis for the feed lips to keep them in place. As bwaites said, it's the rib in the mag body that contributes most to the problem. The rib protruding into the space for the cartridges in combination with the 5.56 dimension follower throws off the tip to rim alignment in standard 5.56 dimension magazines.



Past eight rounds the feed lips didn't engage enough of the rear of the case to hold and retain the cartridge. The alignment moves further and further off axis and only the middle of the case is really engaging the feed lip. PMags and similar clones have thicker bodies, as well as, polymer feed lips with less internal space for the increased diameter of the Grendel case.

Offsetting the step in the follower would change the manner in which the cases stack inside the magazine. Less rib protruding would also aid in changing the relationships of the cases as the stack inside as well.

I'm not having the same issue with the feed lips. Tomorrow if its not raining I'll pop off a few rounds. Also mine don't just blow out of the mag and did the drop test too, from 4 feet loaded.
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[Tedward]

Also looking closer, the bullets do not look parallel, the back end is cocked at an angle. The tips point outward.

Followers definently one issue by looking at the two, the Blue is taller and narrower.

Look at the 2 C-Product Mags. The one stamped 223/556 has additional ribs making the 6.5 bullet go crooked in the metal mag and when I tried to put the Grendel's in that, it also swelled and almost bent. So the internal Ribs on the Lancer is going to be the issue.

When someone gets one from Wilson, we need to know if it has ribs in the front of the mag, that might be the answer if they don't. Is a 7.62 as wide of case as the Grendel? I don't think so, sort of in between if I recall so the front ribs is where the material will need removed.
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Also went ahead and removed the bullets from my lancer, they started ejecting like posted earlier. mine were to tight to pop out apparent on the drop test...

[bigbear_98]

I'm not having the same issue with the feed lips. Tomorrow if its not raining I'll pop off a few rounds. Also mine don't just blow out of the mag and did the drop test too, from 4 feet loaded.
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How many rounds did you have in? I just tried with pmags 30, 20, and gi mags. They all did the same thing that middle man shows but not until about 8 rounds. Then all hell breaks loose.

[gastonglock21s]

I have a 30 round GI mag and a 25 round 6.5 grendel mag to compare. Both have the same number of ribs, but the spacing between ribs is very different

Internal distance between ribs:

30 round USGI mag
Front .520-.563" (tighter at top of rib)
Rear .684-.700" (tighter at top of rib)
Opening at very front of mag .573"

25 round 6.5 Grendel
Front .617-620" (tighter at top of rib)
Rear .788-.800" (tighter at top of rib)
Opening at very front of mag .645"

The 7.62x40 is a .223/5.56 case shortened and necked up to take a .30 caliber bullet. Only the front ribs in the Wilson Combat modified L5AWM mag have to be modified to allow for the .084" or so difference in the size of the neck. I would think that in order for the L5AWM mag to work properly for a Grendel, the space between rear ribs would have to be modified as well. Is there an internal rear rib on your L5AWM mag that can be reduced or is it just a flat wall?

I called around to see if any of the local shops had any of the L5AWM mags so I could measure myself, but all they carry is PMAGS and USGI.

[Tedward]

The Lancer has a flat wall in the rear and you can't remove any material on the front rib or it will make a hole in the mag. My 20 round Lancer would only hold 10 Grendel bullets, where the mag began to bend it wouldn't feed past that. Pmags, no dice at all, it just flexed to much and follower issue. to me, the Lancer is the closest to almost working but no dice till I modify one of my followers. Then I'll know for sure but removing any material on the inside of a Lancer Mag doesn't look like it will help. .

[NugginFutz]

I bought both Stoner and ASC Grendel Mags, in 10 and 20 round flavors, and haven't looked back. They load to the specified capacity without a whimper, and feed all rounds flawlessly. Until someone actually manufactures a bonafide Grendel polymag, I will stick with what works.

[NugginFutz]

I bought both Stoner and ASC Grendel Mags, in 10 and 17 round flavors, and haven't looked back. They load to the specified capacity without a whimper, and feed all rounds flawlessly. Until someone actually manufactures a bonafide Grendel polymag, I will stick with what works.

[Tedward]

I bought both Stoner and ASC Grendel Mags, in 10 and 17 round flavors, and haven't looked back. They load to the specified capacity without a whimper, and feed all rounds flawlessly. Until someone actually manufactures a bonafide Grendel polymag, I will stick with what works.

Take a look at my mags I posted in #51. Do your Stoner and ASC mags have the same ribs on the side? 6.5 on the left and .223/.556 on the right. What is on the floor plates? C-Products or AR-Stoner and ASC? Notice my new C-Products have a different floor plate logo. Also the color, they are stamped SS and shiny black like painted. Very nice finish. They are making changes for the better so it is a good thing, moving up in quality I feel.

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Also just realized the new shinny black mag holds 10 rounds. My others only hold 9, not 10.

Yes the Metal mags work flawlessly and I'll be sticking to them until Polys are offered but wanted to figure out the difference, its the ribs and followers apparently.

[NugginFutz]

My mags are shown in the following:
The 30 is a Brownells 5.56.
The 17 is an ASC Grendel.
The 10 is a Stoner Grendel.



Both Grendel mags use the ASC followers, as seen in the pics.
The principal difference between the 5.56 mag and the Grendel's is the depth of the ribs where the case walls contact the magazine. As one would expect, the ribs in the Grendel mags are significantly less deep. Both the ASC and Stoner mags have similar rib depth, as far as my eyes can see, but I haven't actually measured.

[Tedward]

Looks like all of the 6.5 metal mags are so close it doesn't matter, they all work. As for the followers, my C-products are exactly the same but it looks like the "ASC" was stamped into the follower. If you look at the 6.5, it is the same as my C-products and the ASC. I think the "ASC" was added after manufacturing, that is why there is a square around the initials. Really not relevant, but in my opinion, they are all the same.

Also AR-Stoner are on sale for $10.99 for 10 rounders. Look at the C-products description on Midway, they now added the note "The finish is a durable matte black coating that is resistant to the elements and slightly self-lubricating." That must be where I got my shinny black one. $3.50 more than the Stoner.

[Drifter]

Looks like all of the 6.5 metal mags are so close it doesn't matter...

Yes, and for good reason.

ASC reportedly acquired their machinery from C-Products LLC via a court battle / legal dispute. C-Products LLC reformed (and retooled) as C-Products Defense. IIRC, AR-Stoner mags are made by one of the aforementioned companies, as are AA mags (though AA supposedly puts the mags through extra QC steps).

So it should be no surprise that the design of all four brands is very, very similar.