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czgunner
08-09-20, 21:20
I took a carbine class this weekend. Fired about 400 rounds.
Rifle used was my Colt 6720 which, before the class had about 200 rounds through it. Generously lubed, and bone stock outside of the Magpul handguard, ambi safety, and SSA trigger.
Mags used were Brownells 30 round, with dark grey Magpul followers. Purchase 10 about 3 or 4 years ago. They were new in package before today.
I had 5-6 malfunctions where the round would try to chamber and stop just a smidge out of battery. On finding a dead trigger I would try to clear the malfunction and once had to mortor to extract the round. The rounds looked a bit "bent". Not sure if that is a good description or not. I'm digging through my crap to see if I can find one of the damaged rounds.
My instructor suspected the mags. I isolated one mag, and set it aside, but had one more malfuction with another mag. I used a total of 4 mags in the class.
Ammo used was Wolf GOLD, vintage 3 years ago. Never had an issue with this batch of Wolf before.
Anybody have any ideas?

Here’s a pic of three I was able to find in my bag.
https://uploads.tapatalk-cdn.com/20200811/e1a360352eeb957ea4eb0dd9a28ccad3.jpg

opngrnd
08-09-20, 21:26
I'd try a different type of mag. Grab a new M3 PMAG and see if there are issues.

ColtSeavers
08-09-20, 22:07
Was the wolf gold used to function test/break in, the same ammo used during the class?
What magazines were used to function test/break in the 6720?
Do you have any other magazines to use instead?
What is/are the production date(s) of the Brownells 30rd magazines w/magpul followers?
Do you have another BCG to use instead?
Have you inspected the gas tube/key alignment?
Did you change the safety and trigger before or after the function test/break in?
Can you give your magazine catch another rotation tighter?

ETA: Are the feed ramps still lined up?

czgunner
08-09-20, 22:34
Was the wolf gold used to function test/break in, the same ammo used during the class? Yes, Wolf Gold is all that has been fired in this rifle.
What magazines were used to function test/break in the 6720? I shot all previous rounds with Brownells 20 round straight mags and Lancer 20 rounders.
Do you have any other magazines to use instead? I did not have anything else available during the class.
What is/are the production date(s) of the Brownells 30rd magazines w/magpul followers? 6/13
Do you have another BCG to use instead? Yes, but 6 failures in 400, probably not the BCG?
Have you inspected the gas tube/key alignment? No interference
Did you change the safety and trigger before or after the function test/break in? Installed as soon as I got the rifle home
Can you give your magazine catch another rotation tighter? I guess I could, but I never had a mag retention concern

Replied to message in bold

PrarieDog
08-09-20, 23:08
I have had issues with the lacquer on the steel case causing extraction issues when the rifle is hot Have not had an issue with the gold.

Leonidas24
08-10-20, 05:53
I had some Brownells 30 rd mags from around the same time period, maybe 2012, that had brown followers and experienced something similar to what you described. The tip of the round would hang up on the edge of the magazine as it was feeding and either get stuck nose down in the mag or dented to the point it wouldn't clear the feedramps. The brown followers and springs were swapped out for Magpul yellow followers and standard springs and it continued to be an issue. In all likelihood the feedlips were out of spec to some extent but I didn't feel like screwing with them and in the trash they went. Okay Ind Surefeeds and Magpul M3s are all I use now.

With that said it's only similar to your problem. 9/10 malfunctions the round wouldn't even leave the mag, let alone attempt to chamber.

rvanno
08-10-20, 07:31
I’ve had problems with wolf gold like this in the past. Try some other ammo.

ubet
08-10-20, 07:37
Magpull mags aren’t expensive, why use anything but them?


Sent from my iPhone using Tapatalk

czgunner
08-10-20, 08:17
I have had issues with the lacquer on the steel case causing extraction issues when the rifle is hot Have not had an issue with the gold.

C’mon man. I specifically mentioned Wolf Gold.

markm
08-10-20, 08:32
C’mon man. I specifically mentioned Wolf Gold.

There's an ARFcom invasion here lately.

TonyAngel
08-10-20, 09:27
If the rifle ran fine with the 20 rounders and you only had problems with the 30s, it's probably a safe bet that it was the magazine's.

HCrum87hc
08-10-20, 09:40
I had some Brownells 30 rd mags from around the same time period, maybe 2012, that had brown followers and experienced something similar to what you described. The tip of the round would hang up on the edge of the magazine as it was feeding and either get stuck nose down in the mag or dented to the point it wouldn't clear the feedramps. The brown followers and springs were swapped out for Magpul yellow followers and standard springs and it continued to be an issue. In all likelihood the feedlips were out of spec to some extent but I didn't feel like screwing with them and in the trash they went. Okay Ind Surefeeds and Magpul M3s are all I use now.

With that said it's only similar to your problem. 9/10 malfunctions the round wouldn't even leave the mag, let alone attempt to chamber.

I had this same issue with some Brownells mags I purchased locally around that same time frame. The feed ramp on the mags was too high, causing rounds to snag when attempting to chamber them. I filed them down a little and alleviated the issue, but they're relegated to training mags now.

OP, get some Magpul mags, test them, and call it a day. I'd recommend not using any new gear for the first time in a class. Make sure your set up is squared away the best you can before the class so you don't have to fool with malfunctions and can focus on the instruction.

MistWolf
08-10-20, 11:17
I took a carbine class this weekend. Fired about 400 rounds.
Rifle used was my Colt 6720 which, before the class had about 200 rounds through it. Generously lubed, and bone stock outside of the Magpul handguard, ambi safety, and SSA trigger.
Mags used were Brownells 30 round, with dark grey Magpul followers. Purchase 10 about 3 or 4 years ago. They were new in package before today.
I had 5-6 malfunctions where the round would try to chamber and stop just a smidge out of battery. On finding a dead trigger I would try to clear the malfunction and once had to mortor to extract the round. The rounds looked a bit "bent". Not sure if that is a good description or not. I'm digging through my crap to see if I can find one of the damaged rounds.
My instructor suspected the mags. I isolated one mag, and set it aside, but had one more malfuction with another mag. I used a total of 4 mags in the class.
Ammo used was Wolf GOLD, vintage 3 years ago. Never had an issue with this batch of Wolf before.
Anybody have any ideas?

Did you perform a lock-back check?

Have you tried your AR with standard 5.56 ammo?

sinister
08-10-20, 12:02
There are a number of Brownells magazine lots that are sub-standard where the magazine bodies either flex too much or are over-sized.

I just checked a Brownells 20-rounder stamped 07-13 that won't drop free.

grizzman
08-10-20, 12:21
Did you perform a lock-back check?

Have you tried your AR with standard 5.56 ammo?

Have you tried your AR with the original 20 round magazines that previously worked?

What, if any, troubleshooting have you performed?

czgunner
08-10-20, 12:42
Did you perform a lock-back check?

Have you tried your AR with standard 5.56 ammo?

These 6 malfunctions are the only issues in over 600 rounds. Function checks fine.

ColtSeavers
08-10-20, 13:40
How do the feed ramps look?

Luckily brownels has a great return policy if you just want to return the magazines and get something else.

Norman
08-10-20, 16:17
Use a sharpie or a paint pen to number your magazines, so you’ll be better able to isolate problem mags in the future.

czgunner
08-10-20, 19:02
I think I’m going to send all 10 back to Brownells and get something else.

ETA: Brownells jacked up their return process. It’s online now and won’t let you proceed without an order number. I can’t find it, so I’m calling them in the morning.
Ordered 10 M3 window Pmags for a great price from DSG Arms to replace them.