What ammo was you using? My mini has WC1911 buffers on the op rod and gas block and it will not shoot russian steel cased ammo. It fails to eject and double feeds. Personally I think its underpowered. None of my handloads or any brass cased factory ammo has ever caused me any problems. I like my mini with the 2 buffer setup so I dont plan on changing it to accomodate steel cased ammo.
I was thinking the rear is on the op-rod.
IMHO the Takedown is very accurate. Granted I am sure with a few mods it will prolly drive tacks at a distance. The BX mag is awesome also. I am just kicking myself because I only picked up one instead of a few. Especially after the issues these aftermarkets are giving me. I may just put them in the bottom of my range bag for a SHTF moment and get me a few Ruger mags.
I have run into aftermarket magazines that are to tall and touch the bottom of the firing pin block. Often the difference is so subtle you don't notice the magazine is dragging. Just use a mill bastard file to take a few thousands off the top of the magazine. Promag magazines are especially problematic. There is no need to toss a magazine when you can fix it so simply.
Anything that is 1/2" wide or better, they are made of a hard cured rubber and will hold up to heat well.
I will use a flat pair of pliers and bend the lips of the Promags or tap them down slightly. The metal used by Promag is not as hard as Rugers.
Remember the battle of Athens, TN!
"Work as if you were to live 100 Years, Pray as if you were to die To-morrow." --Benjamin Franklin
As for the mags,,I think my best option IMHO is to just get some factory mags. I haven't been impressed with these since purchase. teach me to buy something without checking this forum huh.
keep your eyes posted because there will be four mags up for sale soon as I get some pics. Unless someone has trades.