I was ready to drop the hammer on 10 of the brownells 20rnd mags, then I started reading the reviews on their site. Surprisingly mixxed reviews. Some people even said they were total junk that jammed constantly.

What does arfcom think?

I have 2 brownells 20s in my range bag that have seen at least 1000 rounds each and they have had zero issues. For aluminum mags my goto are nhmtg or brownells and they both have worked great for me in 20 and 30. My vote is gtg.

I'd say you're good to go. I have about 10 of the brownells 20rds and I have not had an issue. Seem to work as well my colt 20rds.

I was surprised my the reviews on Brownells also. I have 10 and they all work 100% a friend bought 10 and all his work great too.

I just got some from Brownells to try in my 5.45x39, haven't shot them yet so can't comment on function but they don't have an anti-tilt follower and the light grey finish is pretty poor, that is it looks thin and was already scratched on both mags while still in the packaging. But they were on sale for $10 so if they are reliable they're a bargain. Overall quality of construction looks good to me for the price. ASC makes a much better mag but you won't find them for this price.

I have around 40of the 20 round Brownells and am happy with them.
I am about to pull the trigger and order some more.

The 30's are great as well

20s cannot have an anti tilt follower

Brownell's and NHMTG are the best 20 round magazines, period.

I didn't buy any 20s yet, but since the price went back up I am just going to buy NHMTG from 44mag.com.

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Brownells stands behind there products 100 %, if someone has a problem.......... I wonder why..... they prefer to complain and not take action with the supplier.

I am really sorry to say but honesty is always best. So..I have 2 brownells mags and the lame black CS springs that came with them failed me very quickly, maybe a couple hundred rounds. I replaced them with real usgi SS springs and one of them works good and the other still wont hold the bolt open on the last round. I may try some more some day but I will never run the CS springs that come with them.

I have a 20 round Brownell's magazine that I purchased in 2009; it's date stamped.  I think my other 20 round Brownell's mag was purchased as early as 2007, but it's only been used at the range as has remained in my range bag.

The 2009 mag has been used for occasional bench shooting since then, with no failures.  They both have SS springs and the factory followers in them.

Early this year I took the 2009 mag to NTC (large-scale military training exercise in the California desert), and despite daily exposure to lots of sand, and a few "cataclysmic" sand storms, it fired blanks just fine.  This was telling from my perspective, as blanks are not generally regarded as the most reliably functioning cartridge.

I decided that if that particular 20 rounder worked under those conditions, it was good enough for deployment.  I deployed with it and have carried it daily in my M4, preferring it over a standard 30 for its smaller profile.  I must admit that I'm not combat arms, so I'm not going out looking for the fight.  The only time its been used since arriving in the AOR was on the zero and qual range, where it also functioned 100%.

I had to come home for a couple of weeks to escort a guy back who needed medical treatment, but as I head back in a couple of days, that mag will resume use as my daily "in the weapon" feeding device.  I'm very confident with this particular mag.

It is interesting to note that after its use at NTC, 70% of the external finish had worn away.  It showed some finish wear before the exercise, but I suppose the daily weapon clearing and handling did a number on the finish.  I do consider this premature wear for a magazine's finish, as despite the environmental conditions and daily manipulation, I've seen probable Vietnam-era surplus magazines with less finish wear.  The only thing that I can guess is that the dry film finish used in the first few years of Brownell's production wasn't the most durable coating.  Now it shows most of its bronze colored anodized finish.

At any rate, it has still performed well thus far. Despite looking like something from a retro forum or a steampunk thread, I will continue to carry and use it until it starts failing me.

Own 10, no problems

So did they used to come with standard USGI SS springs, because it seems like now days they are CS springs and as much as I love and respect Brownell's their black CS springs are not very good. Sorry.

The 20's and 30's are available with CS or SS springs.
http://www.brownells.com/magazines/rifle-magazines/magazines/ar15-m16-magazines-prod21225.aspx

Lets be clear. What is your basis for this? This is a tech forum, not GD. We dont want to drop "it aint milspec so its bad" rumors.

In every measurable way, the cs springs are better than ss save one: corrosion resistance. So your comment seems odd. I believe you may have got a dud, but that happens all the time with regular mags too. And 1 or 2 bad ones does not make an entire product line "not very good."

I have a 50/50 Mix of CS and SS Brownells springs in about 100 +/- USGI mags.  No discernible difference in performance between either long term.

Gotta tell you so far I'm not terribly fond of Brownells 20 round straight body magazines.

Was at range this weekend with a new one. The black follower is not anti tilt. I had a few jams with it. Trying to figure out how to mill down a green follower to fit.

Thank goodness I only purchased 5. I should have just gotten all Lancers and or magpul. Both of these function without issues.

I ran about 200 rounds of 5.45x39 thru mine and they worked fine. Brownells has them back on sale for $10 now, will probably order more. For 5.56 I prefer the steel 20 round Mako E-Lander (although it's a curved 20 and not a straight) and just ordered some from CTD for $9 each, pretty good deal as they're $25 directly from Mako.

The black plastic follower is sticking in the forward down position .

It happend 3 times and caused jams. This has never happened with my colt , universal straight body mags.