Barrett Store – Magazine, MRAD “B” & Model 98B, .300 WIN MAG/ 7mm REM

Description

When precision matters most, the Barrett Store – Magazine, MRAD “B” & Model 98B, .300 WIN MAG/ 7mm REM is a component that ensures your rifle performs as designed. For U.S. shooters who demand consistent feeding in long-range applications, this factory magazine offers the reliability expected from a brand trusted by military and law enforcement marksmen. Whether you are zeroing at a 1,000-yard range in Montana or building a custom load for competition, this magazine is built to keep your focus on the target, not on the action.

What This Product Is and Who It’s For

This is a genuine Barrett factory magazine, designed specifically for the MRAD “B” and Model 98B bolt-action rifles chambered in .300 Winchester Magnum or 7mm Remington Magnum. It is not a universal or aftermarket component—it is engineered to the same tolerances as the rifle itself. This product is intended for precision shooters, long-range hunters, and competitive marksmen who own one of these Barrett platforms. It also serves collectors who maintain factory-correct configurations for their firearms. If you are a target shooter who values repeatable accuracy or a hunter who needs a dependable spare magazine for extended backcountry trips, this is the correct part for your build.

Key Spec Breakdown

• Compatible Calibers: .300 Winchester Magnum (300 Win Mag) and 7mm Remington Magnum (7mm Rem Mag)
• Capacity: Factory standard 5-round magazine (double-stack, single-feed design)
• Construction: Steel body with a corrosion-resistant black oxide finish; polymer baseplate and follower
• Weight: Approximately 0.4 lbs (empty)
• Dimensions: 3.5 inches tall, 1.2 inches wide, 0.9 inches deep
• Finish: Matte black oxide on steel; non-reflective for field use
• Sights: Not applicable (magazine component only)
• Barrel Length: Not applicable (magazine component only)
• Compatibility: Barrett MRAD “B” and Model 98B rifles; will not fit standard MRAD (non-B) or other bolt-action platforms
• Country of Origin: USA

Feature Deep-Dive

The Barrett Store magazine for the MRAD “B” and Model 98B is constructed from stamped steel, which provides the rigidity needed to handle the recoil forces of magnum cartridges without flexing or binding. The steel body is treated with a black oxide finish that resists moisture and surface rust, making it suitable for humid environments or wet hunting conditions. The polymer baseplate is textured for positive grip during magazine changes, even with gloved hands in cold weather. The follower is designed with a controlled feed angle that aligns each cartridge consistently with the bolt face, reducing the chance of rim lock or misfeeds during rapid cycling.

Inside the magazine, the internal geometry is optimized for the longer overall cartridge length (COAL) typical of .300 Win Mag and 7mm Rem Mag loads. This prevents bullet tip deformation that can degrade accuracy. The spring pressure is calibrated to provide reliable feeding across the full capacity, from the first round to the last. Barrett uses a double-stack, single-feed configuration, which compresses the cartridge stack more efficiently than a single-stack design while maintaining a narrow profile for the magazine well. This reduces the overall width of the rifle at the action, which is a benefit for shooters who use bipods or shooting bags.

One feature that sets this magazine apart from aftermarket alternatives is the positive-latch engagement. The magazine catch slot is machined to precise tolerances, ensuring that the magazine locks securely into the MRAD “B” and Model 98B receivers without wobble. A loose magazine can cause feeding issues under recoil, particularly with heavy magnum loads. This factory part eliminates that variable. Additionally, the feed lips are heat-treated to resist deformation over time, even with repeated use. For shooters who log hundreds of rounds per season, this durability translates to consistent performance without the need for periodic feed lip adjustment.

The baseplate is removable for cleaning, which is important when shooting in dusty or sandy conditions. Underneath, the spring is a constant-force design that maintains tension without taking a set after long periods of storage. This means you can load the magazine to full capacity and leave it for weeks without losing reliability. The polymer baseplate also features a small witness hole so you can quickly verify the magazine is empty without removing it from the rifle. This is a practical detail for range safety and administrative handling.

Finally, the magazine is designed to work with both .300 Win Mag and 7mm Rem Mag without requiring any modification. The internal width and feed ramp angle accommodate the slight differences in case head diameter and shoulder angle between these two cartridges. This dual-caliber compatibility is a cost-effective solution for shooters who own both barrel assemblies for their MRAD “B” or Model 98B. You do not need to purchase separate magazines for each caliber, which simplifies logistics for those who hunt or compete with multiple upper configurations.

Ideal Use Cases

• Long-Range Target Shooting: The consistent feed geometry supports repeatable accuracy for paper and steel targets at distances beyond 800 yards.
• Precision Hunting: For elk, mule deer, or other large game where a follow-up shot may be needed, this magazine provides reliable second-round access without fumbling.
• Competition: In PRS or tactical rifle matches, having a spare magazine that feeds without hesitation is critical for stage transitions and timed strings.
• Range Training: Instructors and students benefit from a magazine that functions identically to the factory test standard, reducing variables during training.
• Collector Preservation: For owners of the Model 98B, keeping a factory magazine maintains the rifle’s original configuration and resale value.

Compatibility Notes

Ammunition: This magazine is designed for factory .300 Winchester Magnum and 7mm Remington Magnum ammunition with standard cartridge overall lengths (COAL) up to 3.34 inches. Handloaders should verify their COAL does not exceed this length to ensure proper feeding. It is not compatible with .338 Lapua Magnum, .308 Winchester, or other short-action cartridges.

Holsters: Not applicable—this is a detachable box magazine, not a handgun component.

Magazines: This magazine is specifically designed for the Barrett MRAD “B” and Model 98B. It will not fit the standard MRAD (non-B) or any other rifle make or model. It is not compatible with aftermarket chassis systems unless they are specifically designed for the MRAD “B” pattern.

Accessories: No additional baseplates, extension kits, or aftermarket springs are recommended for this magazine. Using non-factory components may cause feeding failures. Barrett does not warrant the magazine if modified.

FAQ Section

1. Do you ship this magazine to all U.S. states?
Yes, we ship to all 50 states where firearm components are legal to own. This is a firearm part (magazine) and is not regulated as a firearm itself. However, some states and localities have capacity limits or restrictions on magazine sales. It is your responsibility to verify local laws before ordering. We will not ship to jurisdictions where this magazine is prohibited.

2. Does this magazine require an FFL transfer?
No. A magazine is not a firearm and does not require transfer through a Federal Firearms License (FFL) holder. It ships directly to your doorstep via UPS or FedEx. No background check is needed. For customers in states with additional regulations, we comply with applicable shipping restrictions.

3. What .300 Win Mag ammunition is compatible with this magazine?
Any factory-loaded .300 Winchester Magnum ammunition with a bullet weight from 150 to 220 grains and a cartridge overall length of 3.34 inches or less will feed reliably. We recommend using premium ammunition from manufacturers like Federal, Hornady, or Norma for best results. Handloads should be tested for feeding function before field use.

4. What is the Barrett warranty on this magazine?
Barrett Firearms Manufacturing provides a limited lifetime warranty to the original owner against defects in materials and workmanship. This warranty does not cover damage from misuse, modification, or use of non-factory components. If you encounter a defect, contact Barrett customer service directly with proof of purchase. We also offer a 30-day return policy for items that are unused and in original packaging.

5. Can I return this magazine if it does not fit my rifle?
Yes, you may return this magazine within 30 days of delivery if it is unused, in original packaging, and shows no signs of installation or handling wear. We will issue a refund minus the cost of return shipping. Please verify your rifle model (MRAD “B” or Model 98B) before ordering, as we cannot accept returns on magazines that have been loaded or inserted into a rifle. Contact our customer service team for a return authorization number before shipping.

Closing CTA

This Barrett factory magazine is in stock and ready to ship to your U.S. address—no FFL required. Add it to your cart now to ensure your MRAD “B” or Model 98B has the correct feeding component for your next range session or hunt. We ship from our U.S.-based warehouse within one business day.