Bullet Bio: Nosler Partition

by
posted on September 16, 2015
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
nosler_partition_bb_f.jpg

The story has been told countless times. In 1946 John Nosler shot a Canadian moose with a conventional bullet. It failed, so he designed his own. John knew the key to killing was finding a balance between expansion and penetration. His solution was a bullet with two cores; one in front that would deform and damage lots of tissue and one in the rear that would maintain its integrity and penetrate deep.

The first Partitions were built on screw machines in John's garage and the first moose to meet one died with one shot. A company was built around one bullet and the rest, as they say, is history. The Nosler Partition was the first serious step forward with regard to premium hunting projectiles. 69 years later it remains the hunting bullet by which all others are judged.

The dual lead core separated by a gilding metal barrier is where the partition gets it name, and is what makes it so effective. When the bullet strikes an animal, the front rapidly deforms. The gilding metal jacket peels back and the lead core flattens and wears away. This creates wide wound cavities; it’s a violent occurrence. After the bullet slows to about 1800 fps—inside the animal—deformation stops. But the rear lead core, protected by the partition, is still in tact. By retaining about 70 percent to 80 percent of its weight, the Partition continues to penetrate.

Since 1946 Nosler has continued to tune the Partition. The company has tweaked jacket thickness and hardness and massaged the content of the core. It has been refined to the point of perfection—but they are not cheap to make. A Partition bullet goes through many stages of formation and multiple heat-treating operations. No screw machines anymore—modern Partitions are pounded out on extrusion presses the size of a '64 Lincoln. It’s arguably the best big game bullet for killing critters ever invented. If it has a flaw, other than price, it’s that it sometimes might not shoot bug hole groups. That does not mean the Partition isn't accurate, it's just not a match bullet.

I’ve seen Partitions do amazing things. Most recently, in South Africa, an 85-grain Partition from my wife’s .243 Winchester pounded a big blue wildebeest to the ground with one shot through the heart. Two days before, another 85-grain Partition did the same thing to a gemsbok. I used a 165-grain Partition to take my best mule deer at a 318 yards and I’ve put numerous whitetails in my freezer with the littlest Partition; a 60 grainer out of a .223 Remington.

It might be hard to accept that a 70-year-old hunting bullet is still king of the hill, but look at it this way: the Reese's Cup has been with us for 87 years for the same reasons. That little candy cup perfectly balances the flavors of chocolate and peanut butter like the Partition balances expansion and penetration. They’re both about as close to perfection as you can get.

Latest

W H2026 03 Eastturkey IMG 7028
W H2026 03 Eastturkey IMG 7028

Keys to the Eastern Turkey Hunt

A turkey is a turkey regardless of subspecies, sure, but best hunting tactics often vary depending on geographical location due to the birds’ varying behavior. Translated, killing turkeys back East is different than killing them out West. Check out some Eastern-specific tips below, and stay tuned for a follow-up targeted at our Western readers.

Montana and Utah Celebrating 125th Anniversaries

Two 125th Anniversaries are occurring this year, the first being for the entire Montana FWP, and the second being a key piece of property in the history of the Utah DWR.

First Look: Vortex Viper Shotgun Enclosed Micro Green Dot

Purpose-built for turkey hunting and wingshooting, the Vortex Viper Shotgun Enclosed Micro Red Dot line now adds a green reticle option for those who prefer it in certain lighting and shooting conditions.

First Look: Blocker Outdoors Finisher Series

Blocker Outdoors' Finisher Series is a one stop shop for turkey hunters looking to streamline their clothing and gear in the field. Read on for some of the top pieces in this lineup, designed to keep hunters cool and comfortable, while maintaining easy access to essentials.

Know How: Shed Hunting Hellholes

Mark Kayser's fascination with shed antler hellholes kicked off and continues today in whitetail country. Not satisfied with the occasional shed antler found in stubble fields, hay grounds and open pastures, he turned his attention to the thickest, steepest and nastiest geography in the whitetail woods. Here’s why you should consider putting on your big boy pants for a deep dive into the extremes for shed antler rewards.

New for 2026: Federal X Henry Birthday Boy Collector's Edition Ammo

For 2026, Federal Ammunition has partnered with Henry Repeating Arms to produce a collector's series ammunition. This limited-edition load was developed for Henry's commemorative .45-70 Government Golden Boy lever-action rifle, touted as the Birthday Boy.

Interests



Get the best of American Hunter delivered to your inbox.