Getting Started

The War Lock can be installed by anyone that is comfortable building an AR15 from parts, and it uses those same tools.  We include in our kits the Installation Fixture for building complete barrel assemblies.  The only tools needed to install our kits that we don’t include are a bench vise, AR-15/armorer’s wrench, and receiver blocks/clamps.



Select the types of Barrel Adapter Assemblies. 
The barrel adapter you choose will determine how it mounts to the barrel, and what handguard you can use.

Type 1 Kit is designed to use most two-piece, drop-in handguards (Magpul, A2, etc).  The adapter mounts to the barrel with set screws, and the handguard is retained by the two-piece split ring (Handguard Retainer Assembly).

Type 2 Kit is designed to mount a select number of free float rails (ours, Midwest Industries, etc).  It mounts to the barrel with set screws, the rail is bolted to the barrel adapter.

Type 3 Kit is our universal freefloat mount.  It is designed to replicate the upper receiver threads, allowing for almost any freefloat handguard barrel nut/rail to be used.  It mounts to the barrel with a freefloat bedding compound, the barrel nut/rail is threaded onto the barrel adapter.


Select The Number of Barrel Adapter Kits and Complete Order

Add Flexible Firepower


The War Lock™ system expands your AR-15 caliber range from just the .223/.556 standard, to sizes from the .17 Remington all the way to .50 Beowulf rounds.

To expand your rifle to change 90+ calibers, you only need a complete barrel assembly, a bolt (4 bolts run the majority of rifle calibers), and magazines (some calibers need a different magazine).  After installing your complete War Lock kit, the only thing you will need from us is a barrel adapter kit for the barrel you want to add (used to build the complete barrel assembly).  Feel free to shop around for the best prices on gas blocks, barrels, muzzle devices, handguards, and other accessories.  We take pride in not creating a proprietary system.  Alternatively, we also sell complete barrel assemblies for customers who don’t want to build their own barrel assemblies.

How easy is it to change calibers?  Once your kit is installed, simply put your rifle on SAFE, lock your bolt to the rear, unlock the War Lock, and remove the barrel assembly.  Insert your next barrel assembly, lock the War Lock, and change the bolt and/or magazine (as necessary).  Many calibers only require a barrel and ammunition change. 

There are 4 primary bolts that run the majority of the rifle calibers in the AR-15.
AR-15 Bolt Selection Tool, to help you determine which bolt you’ll need 

War Lock™ Installed Complete Packages


The FTP15 is the Frontier Tactical Pistol line of products. It is an optic-ready, dedicated entry-level AR-15 pistol that includes a few upgrades, but leaves the AR-15 ready for further modification.

FT-15 Rifle

The FT15 BASE RIFLE is the Frontier Tactical Rifle entry-level line of products. It is an optic-ready, dedicated entry-level AR-15 rifle that includes a few upgrades, but leaves the AR-15 ready for further modification. The lower receiver is marked “MULTI CAL” and is a semi-auto AR-15 rifle.

Private: FT-15 Multiple Caliber

***A Federal Firearms License (FFL) is required to purchase this item.***

The Frontier Tactical™ FT-15 Multi-Caliber Packages include all the barrels, bolt carrier groups, and magazines with the rifle that are necessary to switch between the included calibers.

For U.S./Canada sales, please visit our Products or find a Local Dealer.

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