458 SOCOM Conversion Kit

Go big or go home with a 458 SOCOM AR-15!  Arm or Ally enables you to experience the thrill of building, owning and shooting a big bore lead sled at an affordable price!  Converting your AR to a 458 SOCOM requires an upper receiver with a larger ejection port, a 458 SOCOM barrel, and 458 SOCOM bolt carrier group.  Our base conversion kit includes an Aero Precision 458 SOCOM Assembled Upper Receiver your choice between 4 different barrels by Ballistic Advantages, and a Toolcraft 458 SOCOM Bolt Carrier Group. You can also choose to swap out the full BCG for just a 458 SOCOM bolt, add a Gas Block, Gas Tube, and/or Muzzle Device.  Arm or Ally brings you the highest quality parts, from OEM manufacturers without the brand name mark-up.  We believe in transparency, fair pricing, and enabling our customers to build an AR that packs a serious punch!

It’s 2018, the parts are available, and it’s time to build your very own big bore AR with our 458 SOCOM Conversion Kit.  Arm or Ally also offers barrels and bolt carrier groups for your 6.5 Grendel AR conversion.


Toolcraft – When you invest in a Toolcraft product, you are getting the same high quality product offered with high-end rifle “brands” at a fraction of the cost. Toolcraft is a dedicated manufacturer of carriers; this is their expertise, and they do them right. Warrantied for LIFE, if your Toolcraft product fails, their warranty process is simple, and you’ll have a new BCG sent directly to you.

Aero Precision – They’ve introduced the meticulous machining standards of the Aerospace industry to the AR platform.  They’ve rapidly established themselves as a key player in the AR parts market. This medium sized company has beautiful products, built to exacting standards, and their customer service is above average.

Ballistic Advantage – Hand selected materials, experience, and excellent quality control equate to consistent, reliable barrels with a sub-MOA accuracy guarantee.  Arm or Ally is the first and largest stocking dealer of Ballistic Advantage Barrels, and we’re proud to add the SOCOM to the line up of awesome barrels.

458 SOCOM Load Data Link

100% Made in the USA Graphic

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