I've seen countless videos reviewing the recent wave of Glock magazine based AR pattern pistol/rifles, namely the CMMG Guard/Banshee and 100 other random brand Glock mag lower based options. Which magazine type is more reliable for long term/competition use? I've always had great luck with the 9mm colt variety, but when trying to get a Stern 9mm mag conversion block to work with my existing AR, I noticed that it was chewing up the plastic around the mag catch area. This suddenly made me question how long term the whole Glock mag idea is. What if we couldn't get fun sticks anymore (new laws etc) and the existing ones had to last through a lot of insertions? Metal colt magazines will last forever. What are people's experience with Glock mags in this way?

I have both. Neither appears hard in magazines. Might be your conversion block serup.

I've known several folks with 9mm ARs that took Glock mags and no issues...

Although I think all of them, the lower was designed to take Glock mags, not using some adapter or Block deal..
I was wanting to build one just never was able to allocate the funds to the project.  My thought was to go with a lower made for Glock mags, as between the couple of Glocks I have, I've got  a few mags laying around already.  Didn't really want another mag type to buy.

I've been shooting a USPSA PCC (Glock mag New Frontier Billet lower) for a couple of years as well as a Macon Armory block for my SBR....the Glock format feeds directly into the chamber from the single feed mag, and the Colt SBR alternate feeds, and uses a feed ramp on the mag adapter... with the game guys using very short .380 95 grain bullets, several friends have run into feeding problems with the Colt format and short bullets... I shoot a longer 135 grain polymer coated hand load and have not experience any problems with the Glock PCC and I'm probably pushing 9000+ rounds... the Colt less than 1000....I broke the bolt hold open with the Colt the second lock back... the OEM firing pin broke at about 400 rounds, but the replacement Colt OEM pin with the strike end rounded so the hammer hits closer to the center line  has worked without a problem

the blow back AR is a different critter than traditional rotating bolt AR....

I have 2 glock guns, and 2 colt guns.

They all run the same.

And glock factory mags are metal, just like the colt ones are....except they have a plastic shell.

Glock mags will last forever, just like colt ones,  if you use a dedicated lower for them.

So it seems you started a thread over concerns that don't exist for those with dedicated lowers.

_

What the hell is it with these BHO pieces?  Mine bent after about 3 mags.  Stock Colt AR.  Has buffer with a spacer supposedly to prevent this.  

Depends.  On the much older dedicated receivers (I have a few) the Colt magazines feed perfectly.  I'm no expert, but it seems the angle of feeding is better with the Colt style. The problem was more apparent with defensive ammo.

Now, maybe not what you are asking.  Fill both magazines to capacity and drop them on a hard surface....

In theory, double column, double feed will present the rounds faster and more reliably for feeding. The reason we use single feed in pistols is so that the gun isn't UZI/ MAC-10 wide (though MP-443 is double feed).

In practice, they are both highly reliable magazines that you shouldn't worry much about.

Nothing to do with the buffer- Colt had a soft batch of BHOs a few years back.

I believe you were told this in your own thread, with confirmation from myself and everyone else who experienced the exact same issue?

Did you forget that???

WOW....a little obnoxious, aren't you!  I didn't forget anything!  Still haven't received my carbine back from Colt nor an explanation of the repair!  OK with you???

Don't take it so hard.

I'm just hoping to not log on here some day when I'm an old man and see more shock and confusion over a mid-teens batch of soft catches... or hear that you're still waiting for your rifle to come back from Connecticut to swap a BHO.

Finally received carbine back from Colt yesterday.  I'll take it out next week to see how it runs......

Try a dedicated glock mag lower.

Took it out yesterday to the range.  Only got a chance to fire three mags out of it but so far so good.

Having assembled several Glock and Colt AR9.  I have had very few issues with the Colt pattern.  A couple of the Glocks have needed some extra work to get them going.  IF you are buying a complete gun either should work with a manufacture warranty.  If you are assembling your own, I would lean towards Colt pattern.

MAHA

I’ve run a 6450 for near 18years... recently built a pistol..... neither has run jhp reliabily.    FMJ all day.

What’s your needs? Play or protect?

H