Radical Firearms .450 Bushmaster AR-15 16" Carbine Length - 15" M-LOK Rail

Manufactured by Radical Firearms
SKU: FR16-450BUSH-15MHR3
Manufactured by Radical Firearms
2 Reviews
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Items that are regulated by the ATF have restrictions and requirements: 
•Your entire order will ship only to a Federal-Firearm License holder.
•Please contact your local FFL prior to placing your order to ensure they are still accepting transfers.
•A copy of your order/invoice as well as the current FFL license for your local dealer must be emailed to ffl@primaryarms.com.



If you are looking to get into hunting with big bore semi-automatic AR-15 style rifles but are limited to straight walled cases due to arbitrary hunting laws, then the Radical Firearms .450 Bushmaster might be just what you are looking for. This rifle is outfitted with everything you need for a successful hunt. It features 16” barrel machined from 4140 chrome moly vanadium steel with a durable Melonite finish and of course is chambered in the highly versatile .450 BM cartridge. With a large variety of bullet weights and types to choose from, you will be able to find the perfect load for whatever game you want to hunt. This cartridge was originally designed for the AR-15 platform and more specifically for using mass instead of velocity to take large game. This comes at the expense of more recoil, but the Radical Firearms Panzer muzzle brake does quite a bit to help reduce the felt recoil of this thumper round. If your state doesn’t allow big bore bottle neck ammunition for hunting or you simply want to use a tried and true round, then the Radical Firearms 450 Bushmaster AR-15 rifle is the one for you.

  • Chambered in the straight walled .450 Bushmaster cartridge
  • 16” Barrel machined from 4140 chrome moly vanadium steel
  • Melonite finish on barrel and bolt
  • HBAR barrel profile
  • Radical Firearms Panzer muzzle brake
  • 15” Radical Firearms MHR M-LOK handguard
  • Forged 7075-T6 upper and lower receivers
  • Type III hardcoat anodized finish
  • Oversized ejection port
  • Single feed ramp barrel extension
  • Mission First Tactical Minimalist stock
  • Ambidextrous safety, extended bolt release, RF mag release
  • Includes .450 Bushmaster proprietary magazine
  • Made in the U.S.A
This Complete AR-15 is built on forged 7075-T6 aluminum receivers with type III hardcoat anodizing and comes with many additional upgrades to make shooting more fun. It comes standard with a Mission First Tactical Minimalist stock attached to a carbine length buffer tube that allows you to adjust the length of pull. Rounding out the rest of the lower receiver is an ambidextrous safety selector, extended magazine release and bolt release, all made in house at Radical Firearms. The upper receiver is assembled with Mil-Spec parts and features an enlarged ejection port to facilitate the larger cases. To protect your hand and barrel is the 15” Radical Firearms MHR handguard. This handguard features a full length picatinny top rail and plenty of M-LOK slots, so you can set up your rifle for your specific hunt. Step into the world of semi-automatic big bore hunting with this Radical Firearms complete 450 Bushmaster AR.Radical Firearms offers law enforcement grade hardware. Crafted with quality materials and covered by their lifetime warranty, Radical Firearms is an outstanding choice for any budget.
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Barrel CoatingMelonite
Barrel ContourHBAR
Barrel Length16
Barrel LiningMelonite
Barrel Material4140 Chrome Moly Steel
BrandRadical Firearms
Caliber Gauge.450 Bushmaster
Gas System LengthCarbine
Gas System TypeDirect Impingement
Handguard15 in Radical M-LOK MHR Rail
Muzzle DeviceRadical Firearms Panzer Brake
Thread Pattern5/8 X 32
Twist Rate1:16
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.

Ratings & Reviews

2 reviews

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  • 2 stars
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Under gassed

by -

I bought this rifle last November. It would not cycle factory or handloads. The bolt would not lock to the rear. I sent it back to Radical Firearms and they told me nothing was wrong. Basically called me a liar... I then changed out the buffer spring with a flat wire spring which helped it cycle occasionally (still would not lock to the rear). I finally opened the gas port a step; technically voided the warranty, but Radical wasn’t helping anyway. Rifle finally cycles. I will not buy Radical Firearms products in the future.

open and adjust.


if you have failure to eject, i would suggest opening the gas port a bit and buy an adjustable gas block to help mitigate it. over all this is my HD AR. If it can down a bear it can down anyone, its a nasty cartrige afterall. Make sure you get the Lancer Mags 10rds with tromix followers 4+1 it can make a huge difference. This is still a go to gun. Make the best out of everything. It is reliable as soon as you replace the gas block to something adjustable. Mahalo nui.