I had a question concerning magazines. What is the most frequent cause in mags going bad? I just bought two Bushmaster 30 round mags with the green followers, they seem to be working fine but the magazine that came with my Bushmaster stopped feeding properly, why could this be? What mags should I buy next?

I think the ones with the green followers are good but anything else is not going to feed proper. I have 1 with the green follower that I bought after I got my AR and it locks the bolt back and feeds perfect. The one that came with it sucks. It FTF when you get down to the last 5-10 rounds.

I would only go with the ones with the green followers if I were you.

possible weak mag springs.



look in the mag forum for more info

Quoted: I think the ones with the green followers are good but anything else is not going to feed proper. I have 1 with the green follower that I bought after I got my AR and it locks the bolt back and feeds perfect. The one that came with it sucks. It FTF when you get down to the last 5-10 rounds. I would only go with the ones with the green followers if I were you.

The green followers work fine.. BUT.. Ive got quite a few old GI mags withe the black followers.. They also run fine in both semi and full auto..

Provided there is no obvious damage such as bend feedlips, dents on the side, etc, the most common cause for failure of a USGI mag to not feed properly is weak springs.

With marginal springs, the green followers are better.  With good springs, even the old black followers work well.

Quoted: I had a question concerning magazines. What is the most frequent cause in mags going bad? I just bought two Bushmaster 30 round mags with the green followers, they seem to be working fine but the magazine that came with my Bushmaster stopped feeding properly, why could this be? What mags should I buy next?

Suspect this was the bastardized 20 rounder that holds 10 rnds or so........, much like the mags w/ new Colts these mags are absolute junk and should be deposited in the nearest trash-can.

Get yourself some of the older "alloy-metal" follower 20 rnd. USGI mags and you'll be good to go.

Mike

ps - for 30 rounders; stick w/ USGI also or the newer D&H/LaBelle teflon coated ones are also great

Quoted: the most common cause for failure of a USGI mag to not feed properly is weak springs.

 

How to determine a weak spring? Any spec for the free lengths of mag springs for 30 rnds or 20 rnds mags? Thanks.

Quoted: I had a question concerning magazines. What is the most frequent cause in mags going bad? I just bought two Bushmaster 30 round mags with the green followers, they seem to be working fine but the magazine that came with my Bushmaster stopped feeding properly, why could this be? What mags should I buy next?

I've got a bunch of ancient GI mags with aluminum or black plastic followers that function flawlessly.  Mostly "Adventure Line" or "Simmonds" manufactured.  I don't put a lot of faith on the color of the follower, I've seen green ones that weren't worth a crap.  A function test through several loadings will separate the wheat from the chaff.  Good brand mag bodies which fail to function can often be brought back into spec by making sure the feed lips are in spec (measure and compare against a known good mag) and if necessary replacing the spring and/or follower.

I generally tend to buy any GI mag that appears to be in good condition that is reasonably priced. I've picked surprisingly few bad ones following that rule ('ve got several dozen AR mags), and the above mentioned remedies have thus far worked in the one or two exceptions.

HankC

I can tell you as a Glock armorer that they tell us that a Glock Mag spring is "Bad" when you slide off the mag baseplate and you can't see 2 full coils sticking out of it.  If you see only one or one and a half, the spring should be replaced.  I'd take a mag you know is good, slide the baseplate off and invert it to count how many complete coils can be seen sticking up from the follower.  Then take the plate off a bad one and see if there is a difference.  (I'm willing to bet there will be)

Just a suggestion, don't know if you can compare pistol mags to rifle ones but it might be a start until someone with more knowledge can post a response.  (probably not much longer around here!)