My dad has two ASC 30 round 762x39 mags for his AR (calibrated for 762x39 of course) and they’re about several years old and he hasn’t used them since I gave him some ASC 20 round mags a couple years back that actually work.

The problem with the mags is that you can’t seem to fit all 30 rounds in the mag, at most 17-20 rounds, and when you do exceed those 17-20 rounds the follower gets stuck and the rounds just float around when I remove one until I slap the mag, and it becomes considerably harder to put more ammo in.

I’d hate to say to toss them in the trash or leave them in the spare parts box forever. Are there any fixes to remedy this? I’m not sure if our skills can chop down and turn these 30 rounders into 20 rounders and if it’s worth the time and effort. 30 rounders sure stick out like a sore thumb especially when you can only fit half the capacity.

For the time being, I actually managed to fit all 30 rounds in hopes that the mag in a sense “breaks in”

I only have Circle-10 mags I bought and the Arsenal mags that came with my AK.

According to this video and the comments, you aren't the only one with this problem. 

Kind of an odd way to “fix” a C-products mag. I guess it wouldn’t really hurt to try, otherwise go by the comments and smooth out the welding on the insides of the mag

I've found the 20 rounders and 10 round c product mags work best for me

Yeah the 20 rounders I bought him have been working fine, but I just want to get these 30 rounders more functional than their current state.

Well I kinda did what the guy in the video did, hammer the rib (dunno what that was supposed to do) and it seemed to work but I also noticed that the bottom of the mag looked like it was squeezed so I used a big screwdriver as a prying tool to bend it more outwards. Not sure which of the two things I did got the mag to start working better but it appears to feed 25 rounds okayish compared to the 17-20 before I went ham with the hammer and screwdriver.

My fingers hurt from inserting the ammo into the mags repeatively so idk if I’ll get around to the 2nd mag that I’m trying to fix too.
I remember these mags having issues when my dad first got them and I’m  not sure if the bottom of the mag was bent from the factory or just that my dad just mistreated them until I got him the 20 rounders.

I notice the dude in the video is hammering on the primer side of the loaded mag.

I can't find the gun safety rule he's violating, but my instinct tells me there may be one!

Lol yeah, I took the ammo out before I started hammering.

What gen c product mags do you have? My gen 2 work ok with 28 rounds in. Haven't bought the gen 3 mags.

They’re my dads and I’m trying to fix them as he tossed them to the side and uses the 20 rounders I bought him. They’re 30 round ASC mags he bought maybe 2012 or 2013 and I don’t know much about the different generations of 762x39 AR15 mags but the 20 rounders I got him are more recent-ish (2015 I think) and function reliably.

best bet would be to go with what you know functions reliably
having an extra 10 rounds won't mean much if it doesn't feed reliably

Use an ak mag spring too. Read that it helps with the asc 30 rounders. I only bought the 20 rounders cause ... yeahhh... reliability.

I have quite quite a few ASC 30rd 7.62x39 mags, although the earliest one (oldest) was purchased in 2016, so that's pretty recent manufacture, compared to 2012, 2013.  I recall reading that a few years back the AR 7.62x39 mag vendors were in turmoil (ASC & CPD) and lots of reliability issues, but they've really settled out lately.  My current generation of ASC 30rd mags work fine, and hold the full 30.  It does take some pressure getting the last 2 or 3 in there, really looking forward to the Mag LULA for these mags, should be out Feb 2018 (so they say).  MagLULA just recently posted a photo of the loader, up until a few days ago, they only had the CAD drawing, so, maybe progress.

However, I only recommend the CPD mags for others, because they seem to work straight away.  For my ASC mags, before initial use, I disassemble them, clean them out with BraKleen, and re-lube them with spray dry-lube or silicon spray.  I also deburr the sharp edges for smoother feeding, but that doesn't affect being able to jam the full 30 in there.  Well anyways, because of this OCD prep work, I only recommend CPD for others.

I've also heard about the same problem you're having, not being able to load the full 30, on arfcom, it pops up every now and then, so, I don't think you're the first, and I don't think there's a workable solution.  I think it was a premature design.  I think there was a redesign, both CPD and ASC, because for a while, a couple years back the 30rd mags weren't readily available for purchase, CPD only had 28rd mags, etc.  something like that, I had a bunch of CPD 28rd mags on back-order from Brownells during this drought, when they finally filled the order, Brownells sent me the new-gen 30rd mags.  no biggie.  My 30rd CPD mags also hold the full 30, equally difficult to load the last 2 rounds, and they work fine.

because the internet consistenly bad-raps the ASC mags, I try to use them more often to see if they'll hiccup, beat them to death, but sofar, they work fine, no issues at all, mag dumps galore.

So essentially they're quite the paperweight. We've had more luck with the asc 20 rounders that seem to be fine except the finish on them is kinda peeling off from improper storage, but still works perfectly fine.

So essentially they're quite the paperweight.

well, you could use them at KHSC rifle side, what with their not-more-than-5-rounds-in-the-mag limit, and the prominent banana shape will announce to all that you're shooting commie bullets, you know, for the coolness factor.  this will distinguish you as one of those rare individuals willing to try something different than the standard run-of-the-mill black rifle shooting ho-hum .223/5.56.  leading edge of progress and revolutionary thinking.  or, does that describe your dad, since he's the one who purchased these?  in that case, he wasn't on the leading edge, he was on the bleeding edge, which is now the leading edge, well, 7.62x39 AR-15's got a lot of followers, so maybe not even leading edge any more.  all in fun.

I think he was just unsatisfied with the result of a 223/556 against a wild pig but liked the AR platform. That plus it was easier for him to find 762x39 soft points.
He said he used to have a 303 lee Enfield smle (stolen, then recovered several years later after the burglar died in a car accident, and then sold it or so i’ve been told) but he didn’t like it for hunting and ammo was hard to find. He has a odd taste in my opinion but I really wish he kept that Enfield.