The Firing Line Forums - View Single Post - Issues AC-556 with new Ruger 30 round magazines?

Skans · June 23, 2011, 09:34 AM

It's the magazine. I have an AC556. I don't have one of the new 30 round magazines. I have a couple of 20 round magazines, and 2 aftermarket 40 round magazines and a Betamag. One of the aftermarket magazines will need to have the feed lips adjusted (bent down a little) every now and then - the other aftermarket magazine never gives me any problems. The 20 round magazine works perfectly every time.

When I purchased the beta mag with the mini-14 feed tower, it fit so terribly that I could hardly pull the bolt back. At first I was reluctant modify the feed lips on it, but after reading other accounts of problems, I found that it was normal to have to trim the feed lips to get it to work. I ended up having to shave 1-2 millimeters off of each side, a tiny bit at a time. It works perfectly now, but I was surprised at how terribly "off" it was. I suspect that its the same thing with your 30 round mag. The bottom of the bolt actually has to pass through the feed lips.

This is the first I've heard about a factory mag having this problem. I really don't understand how hard it is to make magazines to specifications! The interesting thing is that the Mini-14 - AC556 is actually very forgiving - the magazines don't need to be perfect. It's just that there is so much slop out there in the way companies (maybe Ruger now included) manufacture their magazines.

June 23, 2011, 09:34 AM	#3
Skans Senior Member Join Date: November 20, 2008 Posts: 11,132	It's the magazine. I have an AC556. I don't have one of the new 30 round magazines. I have a couple of 20 round magazines, and 2 aftermarket 40 round magazines and a Betamag. One of the aftermarket magazines will need to have the feed lips adjusted (bent down a little) every now and then - the other aftermarket magazine never gives me any problems. The 20 round magazine works perfectly every time. When I purchased the beta mag with the mini-14 feed tower, it fit so terribly that I could hardly pull the bolt back. At first I was reluctant modify the feed lips on it, but after reading other accounts of problems, I found that it was normal to have to trim the feed lips to get it to work. I ended up having to shave 1-2 millimeters off of each side, a tiny bit at a time. It works perfectly now, but I was surprised at how terribly "off" it was. I suspect that its the same thing with your 30 round mag. The bottom of the bolt actually has to pass through the feed lips. This is the first I've heard about a factory mag having this problem. I really don't understand how hard it is to make magazines to specifications! The interesting thing is that the Mini-14 - AC556 is actually very forgiving - the magazines don't need to be perfect. It's just that there is so much slop out there in the way companies (maybe Ruger now included) manufacture their magazines.