At RFV Tactical, we've never been much of a fan of holsters that have integrated magazine carriers. Part of the reason for this is that the "side-car" style of holster and mag carrier is typically made specific for a particular gun and it's associated spare magazine and is only applicable for appendix carry. Our main focus has always been making holsters and mag carriers that are as universal fit as possible, so a gun/mag specific holster combo wasn't something that we were really interested in making.
When side-car style holsters first came out (pioneered by T.Rex Arms) they were a one-piece rigid design, which seemed like it wouldn't be comfortable for a lot of different body types. This is the main reason we have always made mag carriers that were separate from the holster, as we know that there are a lot of people that prefer to carry a spare mag on the outside of their belt near their hip, or they don't carry a spare magazine at all.
The side-car style holster later evolved into a two-piece design (pioneered by Tier1 Concealed) that allowed some flex between the holster and the mag carrier using a strip of leather or a bungee cord woven between holes to connect the two pieces, which increased the comfort level for different body types.
While the newer flexible designs appear to be much more comfortable, we had never really given any consideration to coming up with our own side-car style holster and mag carrier combo until we recently started carrying full-size heavier all steel handguns regularly.
We are always trying new things behind the scenes to improve our products, so we started working on a way to attach our existing universal fit mag carriers to our existing full-size weapon mounted light indexing holsters without changing the design of either just to give everyone (including ourselves) another option. We use a 1.5" wide strip of rubberized nylon webbing to attach the mag carrier to the holster to be as flexible as possible for maximum comfort. One side of the nylon strip attaches to the mag carrier via existing holes and keeps the mag canted at a 10 to 12 degree angle. The other side of the nylon strip attaches to the holster via a vertical line of holes drilled into the holster's oversized sight channel. These holes provide three different positions of height adjustment for the mag carrier that will also affect the cant of the holster in relation to the mag carrier.
Due to the attachment method and design of both units, the options for belt clips are limited to what is pictured below.
We have found that locking the holster and mag carrier together substantially increases the overall stability by spreading out the contact points on the belt to distribute the weight across a larger area. This is very advantageous when carrying a larger or heavier gun. This increased stability also keeps the gun and the spare magazine in a fixed position on the belt so that they are always in the exact same place and angle if/when you need to access them quickly. If you are interested in this option, we will attach one of our universal fit mag carriers to one of our full-size weapon light holsters at no extra charge when you purchase a mag carrier with the holster!
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