20 RD AR-15 Mags someone fill me in?

Nighthawk

Ive been going through some books on the AR-15 .223 Rifle,just to freshen my memory on a few things.I remember when we were trained on the use of the AR-15,one of the Instructors telling us to never load more than 18RDs in a 20 RD Mag.He said it will cause jams, double feeds and make the gun venerable to problems.But the 30RD and other Mags dont have this problem.I know Bushmaster and most of the Major AR-15 Brands dont make a 40RD Mag.Why is it they recommend only 18RDs to be loaded in the 20RD Mags?And does anyone make a reliable 40RD Mag?Bushmaster sales 40RD Mags but they are quick to tell you they are after market brands.So can someone tell me of a good 40RD AR-15 Mag and where to find them?

Rugster




"Toujours Pret"

hughbetcha

I was also instructed to load only 18 rounds into 20 round magazines. I have also been informed by military instructors that it is OK to put 30 rounds into 30 round mags. I have experienced double feeds when using 20 round mags fully loaded. The explanation that was given to me is that the straight magazine cannot properly feed the full 20 rounds and because the 30 rounders are curved(articulated) they can feed all the rounds without jamming. If you stack a bunch of loose rounds one on top of each other you will see that because of the shape of the case, they stack up in a curve. After about 18 rounds, this curve gets rather pronounced.

I have also seen 20 round magazines that are slightly longer and have a curve to them, in which it is supposed to be OK to load the full 20 rounds. USA Mags uses this shape with their 20 rd. mags

mark christian

Hughbetcha covered the 18 round in a 20 round magazine subject perfectly but with the new and imporoved followers this is less of an issue today than it was years ago. I really prefer the looks of the 20 round magazines and seldom use 30 round magazines in my own AR-15s and M16s. The ONLY 40 round AR magazines I have ever come across that worked reliably were those made by Sterling in England back in the late 1970's and early 1980's. These were cut on the body so that they could be used in eiher the AR-15/M16 or the Armalite AR-180/18 which Sterling was then producing under license. I think Gun Parts Inc. had some of these avaialble for sale last year but I can't remember the price. The USA brand 40 round magazines are junk and either won't lock into the magazine well, or they go too deep into the magaizne well causing the carrier to destroy the follower or deform the magazine lips and then can't be removed without a struggle and they won't feed propery, or will cause jams when they do feed. Other than those minor issues they work great!

"Nothing can ever be made 'idiot proof' because idiots are simply too clever"!
Mark T. Christian

Lowrider

I have dozens of 20-round mags for my AR-15. New and used U.S. military mags, new and used Colt mags, new and used Orlite mags, steel mags, aluminum mags...

I load all of them with 20 rounds and have never had any problems.

Lord Lowrider the Loquacious.

Member:Secret Select Society of Suave Stylish Smoking Jackets

She was only a fisherman's daughter,
But when she saw my rod she reeled.

alledan

If you are worried about it-just drop in a green mag follower. 18 rounds will be all that you can load![:D]

Hangfire

I use U.S.G.I, Colt, and Orlite....all 20 rounds. I don't like the looks of the 30's.Never had a problem with loading a full mag.Orlites are my favorite and I very seldom use the others. I like the low maintenance and strength of the nylon mags.

Love them Pre-64's!!!!-Bob