.450 Bushmaster Ammo
The .450 Bushmaster is a straight-walled, large-bore cartridge designed specifically for the AR-15 platform, launching .452-caliber bullets at 2,200–2,250 fps from a 20” barrel. Developed in response to Michigan’s straight-walled cartridge deer hunting regulations, the .450 Bushmaster has become one of the most popular AR-15 hunting cartridges in the Midwest and beyond. It delivers .45-70-class energy at 100 yards in a semi-automatic, detachable-magazine platform using standard AR-15 lowers with only a barrel, bolt, and magazine change required.
Read our full .450 Bushmaster Buying Guide ↓
Why the .450 Bushmaster Exists: Straight-Walled Cartridge Hunting Laws
Several Midwestern states — Michigan, Ohio, Indiana, and Iowa among them — restrict deer hunting in certain zones to straight-walled cartridges rather than bottlenecked rifle cartridges. This was originally intended to limit range in densely populated rural areas. The .450 Bushmaster was engineered to meet these regulations while delivering genuine deer-stopping power in a modern semi-automatic platform. It’s a genuinely effective cartridge independent of legal requirements: a 250-grain bullet at 2,200 fps produces over 2,600 ft-lbs of muzzle energy — more than adequate for deer, hogs, and black bear at typical hunting ranges.
.450 Bushmaster Ballistics and Effective Range
The .450 Bushmaster is a short-range cartridge by rifle standards. A 250-grain load drops roughly 6” at 200 yards and 20” at 300 yards from a 100-yard zero — trajectory is steep compared to bottlenecked cartridges. Practical hunting range is typically 150–200 yards, which is entirely appropriate for timber and mixed-terrain hunting. Within that range, the .450 Bushmaster hits hard, and modern soft-point and polymer-tip loads perform reliably on deer and hogs. It’s not a long-range cartridge, but inside 200 yards it’s a very effective one.
.450 Bushmaster vs. .458 SOCOM vs. .50 Beowulf: Big-Bore AR Comparison
These three cartridges occupy the same niche — big-bore AR-15 cartridges — but differ meaningfully. The .450 Bushmaster has the best ammunition availability and the lowest price per round of the three. The .458 SOCOM offers a wider bullet weight range (250–600 gr.) and was specifically designed for suppressed military use. The .50 Beowulf is the most powerful but has the least ammunition availability. For hunters who want to buy ammo at any sporting goods store, the .450 Bushmaster is the practical choice. The .458 SOCOM is the choice for shooters who want subsonic suppressed capability.
Building a .450 Bushmaster AR-15: What You Need
Converting a standard AR-15 lower to .450 Bushmaster requires three components: a .450 Bushmaster upper (barrel and bolt carrier group), a .450 Bushmaster magazine (standard AR-15 magazines will not work — dedicated single-stack mags are used), and .450 Bushmaster ammunition. The lower receiver, buffer, spring, and all controls remain standard. This makes the .450 Bushmaster one of the most cost-effective big-bore AR conversions. Complete .450 Bushmaster uppers are available from Ruger, CMMG, Bear Creek Arsenal, and others.
Best .450 Bushmaster Hunting Loads
Hornady’s 250-grain FTX (loaded in their LEVERevolution line adapted for the Bushmaster) is the benchmark hunting load — reliable expansion, good penetration, and widely available. Federal’s 300-grain Trophy Bonded Tip is an excellent option for larger game or when maximum penetration is needed. Remington offers a 260-grain Core-Lokt that is a proven deer load at a competitive price. For hog hunting where multiple shots may be needed, the Remington Core-Lokt or Winchester Power-Point are practical volume options.
Shop .450 Bushmaster Ammo and Big-Bore AR Rifles at Impact Guns
Browse all rifle ammo at Impact Guns. For other big-bore AR cartridges, see our .300 Blackout page. For AR-15 rifles chambered in hunting cartridges, see our AR-15 rifles page and hunting rifles.