Quoted:
Most cost effective is a used Army LBE vest. For less than $20 you can carry 6 mags and have 2 extra pockets for clips. Add a belt , some ALICE pouches and a butt pack and you can load up with more ammo than you comfortably carry.
It's a vest, not a chest carrier,
per se, but hard to beat for utility and low cost. Decent used units are useful and cheap.
The first version of the Load Bearing Vest (LBV) had vertical mag pockets, and a solid fabric underlay. The Improved Load Bearing
Vest (ILBV} had a mesh underlay (cooler), and mag pockets angled toward the center of the user's chest, which were MUCH more user-friendly. The ILBV is MUCH preferable to the older LBV.
The big "D" rings on the back of the vest were intended to accomodate the last version of the USGI buttpack, distinguished by its' woodland camo pattern, black fastex buckles, and unique top straps which interfaced with the aforementioned 'D" rings. I hate buttpacks, but this version was the best of a bad lot, and actually useful because it was quickly attached/detached without mucking around with the rest of the vest.
Both are easily available, and cheap. I wouldn't feel at a disadvantage with a well-set-up ILBV-based rig at all.
It occurs to me that a lot of users are spending a LOT of money with various vendors for what they consider High Speed, Low Drag gear. That's fine.
I submit a good many users might be better served by utilizing surplus mil gear.
Certainly most users requirements will not be in the same category as a person in the active military, nor will Uncle Sam be there to provide for their basic needs for free, let alone re-supply.
If one has the money, and the need, by all means go for it.
If one is on a budget, GI milsurp, carefully chosen and configured, will do you very well, indeed. And at a fraction of the cost of gear whose additional capabilities (IF ANY) will seldom be used.
This a good example of the "90/10" Rule.
You can to to 90% of your goal for a reasonable price. BUT that last 10% towards your goal has a
steeply increasing price.
For somebody starting out, or even most users, USGI milsurp, intelligently chosen and intelligently configured will serve
very well.
The money you save can be better spent on ammo and/or training, both of which are far more important than who made your pistol mag pouch.