Bushmaster M4A3
About this product
The Bushmaster M4A3 Patrolman's Carbine is a standard mil-spec-pattern AR-15 chambered in 5.56 NATO/.223 Remington, built on Bushmaster's XM-15 platform with a 16-inch chrome-lined barrel and a flat-top A3 upper receiver. It's a straightforward, general-purpose AR-15 rather than a specialty or lightweight build, and it's still a current production model in Bushmaster's lineup.
What does 'A3' mean on this rifle?
The A3 designation refers to the flat-top upper receiver with a full-length Picatinny rail, which lets you mount any modern optic or a detachable carry handle instead of being locked into the fixed carry-handle sight system of older A2-pattern rifles. This carbine ships with a detachable carry handle and dual-aperture rear sight so it's usable with irons out of the box, while leaving the rail open for a red dot or scope.
What are the core specs?
It runs a 16-inch, M4-profile, chrome-lined barrel with a 1:9 twist and six grooves, a birdcage flash suppressor with an M203 cut and bayonet lug, and a six-position collapsible stock. The upper and lower receivers are forged 7075-T6 aluminum with a manganese phosphate coating for corrosion resistance, and it ships with 30-round magazine capacity.
Is this rifle meant for hunting, home defense, or range use?
A standard 16-inch-barrel AR-15 like this is versatile enough for range shooting, home defense, and varmint or predator hunting depending on the ammunition loaded, and the removable carry handle plus flat-top rail mean you can configure the optic setup to match whichever of those uses you prioritize.
The rifle's fixed front sight base and removable carry handle give it a traditional AR-15 profile, and because the upper and lower receivers use standard mil-spec dimensions, it accepts the wide range of aftermarket handguards, stocks, and grips available across the broader AR-15 aftermarket if you want to customize it down the road.
Ammunition compatibility is straightforward, since 5.56 NATO and .223 Remington are among the most widely available and affordable centerfire rifle calibers on the market, making this a practical choice for high-volume range use as well as home defense or hunting depending on your load selection. Bushmaster backs its rifles with a standard limited warranty, and parts commonality with the broader AR-15 platform means replacement components and gunsmithing support are widely available compared to more specialized or proprietary rifle designs.
Bushmaster has been producing AR-15-pattern rifles since the 1970s and the XM-15 line specifically has been a mainstay of their catalog for decades, so this M4A3 Patrolman's Carbine represents a well-established, unspecialized take on the platform rather than a newer or more novel design - a reasonable pick if you want a dependable, general-purpose AR-15 rather than a build optimized for one narrow use case.
What should California buyers check before ordering?
California treats semi-automatic centerfire rifles with detachable magazines under its own feature-based 'assault weapon' rules, separate from federal law, and compliant configurations (featureless builds, fixed 10-round magazines, bullet-button configurations, etc.) vary depending on how the rifle is built and sold. Confirm this specific configuration's current California legal status and required features with your FFL before ordering - do not assume a standard AR-15 configuration is automatically compliant.
How does the purchase process work?
As a firearm, this carbine ships to a licensed FFL dealer rather than to your home address. You'll complete a background check and any required state waiting period before taking possession. Checkout here runs through secure checkout, and FFL transfer fees are set separately by the receiving dealer.
FFL transfer required
This item is a firearm and ships only to a licensed FFL dealer, never to a home address. At checkout, enter your preferred dealer as the shipping address, or leave it blank and we will assign a licensed dealer near you at no extra cost. You complete the background check and paperwork with the dealer when you pick up.
California buyers: handguns must be on the California roster for delivery to a California FFL, a Firearm Safety Certificate (FSC) and DROS are handled at the dealer, and the 10-day waiting period applies. Out-of-state buyers receive the firearm through their own local FFL under their state's rules.
Pros & cons
What works
- Flat-top A3 upper accepts any modern optic via Picatinny rail
- Chrome-lined 16-inch barrel for corrosion resistance and easy cleaning
- Removable carry handle included for iron-sight use
- Well-established, mil-spec-pattern AR-15 platform
Trade-offs
- California's feature-based rifle rules require confirming compliant configuration before ordering
- Standard collapsible stock and furniture, not a lightweight or specialized build
- 30-round factory magazine exceeds what many states allow
Key attributes
| Transfer | Ships to your FFL dealer |
| Caliber | 5.56 NATO/.223 Remington |
| Capacity | 30+1 |
| Barrel Length | 16 in, chrome-lined |
| Upper Receiver | Flat-top A3, forged 7075-T6 aluminum |
| Stock | Six-position collapsible |
Frequently asked questions
- What caliber does it use?
- 5.56 NATO/.223 Remington.
- What barrel length and profile?
- 16-inch, M4-profile, chrome-lined barrel with a 1:9 twist.
- Does it come with a red dot or scope?
- No, it ships with iron sights (removable carry handle, dual-aperture rear); optics mount to the flat-top Picatinny rail separately.
- Is this rifle configuration legal in California?
- California's rules for semi-automatic centerfire rifles are feature-based and separate from federal law - confirm this specific configuration's compliant status with your FFL before ordering.
- Can it ship to my home?
- No. It's a firearm and must transfer through a licensed FFL dealer after a background check.
- What magazine capacity does it ship with?
- A 30-round magazine, though California magazine-capacity rules and configuration requirements apply separately - confirm with your FFL.