Have had both the metal and the new plastic mags in .223 and 6 Arc in Axis rifles...... I'll take the plastic. Nothing to tweak (or needed to be tweaked) with the plastic mags and it immediately cured the feeding issue for one of the 6 Arc rifles that took multiple metal magazines to one that worked. The plastic ones fed much smoother as well.
I think you just got one with a bad spring.
Just curious... with the plastic .223 mags, have you checked to see what the max OAL that will fit in them is? I have not gotten my hands on one yet, and I'm curious. With the metal mags I can get out to 2.45"ish. I've been tempted to call Savage and order one of the polymer mags to try, but only if will allow similar OAL to load and feed properly.
To chime in a bit here on the mag issue, I bought a 5.56mm Trail Hunter Lite a couple years ago, and the original (metal) magazine that came with the gun wouldn't feed worth a crap. I started a trouble ticket on their website, and they offered to take the whole rifle back to look at it, or send me another mag to see if it would fix the feeding issues. I had them send me a new (metal) mag and it worked mostly fine, I will still get a very occasional hangup with 75gr Speer Gold Dot ammo, but it has a small blunt tip that tends to catch on the breechface right below the chamber. That is one down side of the Savage barrel/bolt design IMHO. Flat breech face.
The new mag feeds tipped bullets (ELDm's, TMKs etc), FMJ, and OTM just fine. Interestingly, the new magazine has a matte blue finish, as opposed to the glossy blue finish of the original.
After setting the old mag aside for most of the last two years, I ran across a video of how to disassemble the Savage mags on youtube earlier this spring, and that set the wheels in motion for me to tinker a bit with the original magazine. After some trial and error tweaks to the feed lips, that magazine now functions 99% of the way the new one does, even with the Gold Dot.
Everyone likes to bag on Savage rifles, and particularly on their feeding... while ignoring the fact that even the beloved Rokslide Special Tikkas sometimes struggle to feed .223 properly. IMHO, a big part of the problem is trying to feed .223 in an action that was really designed around .308 sized/length cartridges. Savage has had issues... but so have quite a few other rifles/brands. My older Savage .30-06 is a stagger feed gun, and I've had exactly ZERO issues with feeding in that gun, ever.
And don't even get me started on clunky feeding and mag issues with AICS mags... I've seen and experienced enough of that, that I hesitate to use it on a hunting gun
That said... I am looking at "building" a custom .223 or .223 AI gun... and It'll probably end up fed from AICS mags of some sort. I wish MDT made a 5rd .223 metal body mag that was close to flush in their bottom metal.
