20-Pack .28 Caliber Brass Bore Brush

In stock
SKU: BR-0001-028-p20

High-velocity 7mm cartridges push jacketed bullets hard — and that means heavy copper fouling in the bore. This .28 caliber brass bore brush is sized for the 0.284" / 7mm groove diameter, using phosphor bronze bristles to cut through copper and carbon buildup without risking damage to your rifling.

The 7mm family includes some of the most capable long-range hunting cartridges available — 7mm Rem Mag, 7mm-08, and .284 Winchester among them. These cartridges generate higher velocities than most .30 caliber rounds, which translates to faster copper fouling accumulation. A bore cleaning routine after every shooting session isn't just recommended — it's how you protect the accuracy these cartridges are known for.

Note: this is a rifle bore brush for .28 caliber / 7mm firearms, not a 28 gauge shotgun brush. Apply bore solvent, push this rifle cleaning brush through fully, follow with patches. Straightforward gun cleaning for a caliber that rewards attention to detail.


Caliber:
.280 Rem, 7mm-08, 7mm Rem Mag
Product Type:
Bore Brush
Firearm Type:
Rifle
Use Case:
Bore Fouling Removal
Pack Size:
10-Pack, 20-Pack, 3-Pack, 5-Pack, Single
Bristle Material:
Phosphor Bronze
Core/Stem Material:
Twisted Wire (Brass)
Bore Diameter (in):
0.284
Thread Size:
8-32
Country of Origin:
Imported (China)
Brand:
GUNNIX
Is a .28 caliber bore brush the same as 7mm?
Yes. ".28 caliber" and "7mm" both describe a bore diameter of 0.284 inches. The two terms are interchangeable. Any brush labeled .284, .28 cal, or 7mm fits the same rifles. Don't confuse this with a 28 gauge shotgun - that is a completely different product with a 0.550-inch bore diameter.
What cartridges use a 7mm / .284 bore brush?
This brush fits every rifle chambered in a 7mm-bore cartridge: 7mm Remington Magnum, 7mm-08 Remington, .280 Remington, .280 Ackley Improved, .284 Winchester, 7mm PRC, and 7mm Weatherby Magnum, among others. The bore diameter is the same across all of them — only the case dimensions and chamber differ.
Can a bronze bore brush damage my rifle barrel?
No. Phosphor bronze is significantly softer than barrel steel. The bristles flex and scrub fouling without scratching the bore or rifling lands. Barrel makers and gunsmiths have confirmed this repeatedly. The real damage comes from not brushing - copper and carbon fouling left in the bore can pit the steel over time if solvents and brushes are neglected.
What is the best bore brush material for a 7mm rifle?
Bronze is the standard. The 7mm Rem Mag and similar cartridges push bullets at high velocity, which deposits copper jacket material into the bore. Bronze bristles are stiff enough to loosen that fouling. Nylon is useful when soaking with aggressive copper solvents - it won't give false blue-green readings on your patches. For regular cleaning, bronze is the workhorse.
After brushing, should I use a jag with patches or a bore mop?
A jag with patches is the better choice for precision rifles like the 7mm Rem Mag. The tight-fitting patch wraps around the jag and contacts the entire bore surface, giving you a clean read on how much fouling remains. You can see copper residue as blue-green on white patches when using copper solvent. A bore mop absorbs more but hides the visual feedback you need to know when the bore is truly clean.