The first time I hunted deer, at the age of 12 (shirt-tailing into a big annual family camp with a neighbor), I took a buck. I shot that forkhorn mule deer after being left to my own devises, sneaking into a herd and shooting him offhand at about 100 yards. The factory-loaded Power-Lokt took out both lungs. A couple years later, I hunted elk – under similar circumstances – shooting a 5x5 bull. After tracking it through deep snow for miles, I took the bull broadside through the lungs at 200 yards with a handloaded Nosler Partition. That bull didn’t make it out of my sight.

Both animals were taken with a Remington Model 700 ADL, chambered in .243 Winchester. I used that rifle to take many more big-game animals before leaving high school, and too many varmints and predators to accurately recall.

I eventually burned the barrel out of that .243 Winchester, feeding it too many hot-loaded 60-grain Sierra hollowpoints. It was never replaced, and I had not shot another .243 Winchester since. But when Linda Powell, O.F. Mossberg & Sons’ press relations guru, invited me to join her and a group of gun writers in Kansas in early December, nostalgia got the best of me, choosing Mossberg’s Patriot Predator chambered in .243 Winchester (currently retails at $519). The barrel is threaded to accept the GemTech Tracker suppressor I intended to use during the hunt.

Forty-some years ago I loaded nothing but old-fashioned cup-and-core softpoints and hollowpoints, and only Hodgdon and IMR powders that were already classics when I was young. Those loads obviously worked quite well, as I never found the cartridge lacking. In this series, I was curious to see how advancements introduced since the late 1970s and early 1980s might have changed the dynamics of my old favorites.

All listed powders either did not exist or had not reached American shores when I was young. Most Finnish-made Vihtavuori powders have actually been around quite some time in Europe, undergoing continuous improvements for temperature stability and cleanliness. N140 is one of my accuracy favorites, while N560 is a newer formula that includes increased nitroglycerine content that coaxes higher velocities out of many popular cartridges. N555 is one of the company’s newest – introduced to fuel the Creedmoors – a high-energy, temperature stable, “anti-fouling” formula.

Hodgdon’s Superformance is also relatively new, the magic dust that fuels Hornady’s velocity boosted Superformance ammunition. Winchester’s StaBALL 6.5 appeared in 2019, the first temperature stable, copper-erasing ball powder and obviously inspired, again, by the 6.5 Creedmoor.

Shooters World powders are undoubtedly new to American shooters, though they are made in the Czech Republic by Lovex Propellants, which has been supplying European shooters for quite some time. They include updated chemical stabilizers to offer improved consistency, cleanliness and make them more environmentally friendly. Long Rifle is another 6.5 Creedmoor ideal, SW-4350 offering a burn rate slower than other 4350 powders.

Alliant Reloder powders are a handloading staple, with the newest examples offered here. Swedish-made Reloder 16 is an accuracy and velocity favorite in my 6mm Creedmoor, including TZ Technology that offers exceptional temperature stability. Swiss-made Alliant Reloder 26 includes EI Technology that introduces temperature insensitivity plus added velocity in the .243 Winchester.

Western Powders Accurate 4350 provides a more temperature stable formula than my old .243 Winchester standby- IMR-4350, and a burn rate slower than H-4350. H-4831sc is one of the Extreme Series of Hodgdon powders, offering stability across a wide range of temperatures. Finally, IMR Enduron powders – IMR-4451 and IMR-7977 used here – were introduced in 2015 and feature both temperature insensitivity and a copper-fouling eraser. N140 was the fastest powder used, while Reloder 26 was the slowest.

When contemplating “modern” in relation to bullets, I had in mind a couple monolithic copper numbers from Hammer Bullets and Hornady’s new CX, and some heavier VLD/ELD-style bullets from Berger and Hornady. Then I recalled the .243’s standard 1:10 twist rate and I needed twist rates in the neighborhood of 1:9 to 1:8 to shoot the bullets, so they were abandoned. I was still determined to maximize ballistic coefficient (BC) and terminal performance. Digging through my 6mm bullets, I found a Nosler Partition 85-grain, Berger VLD Hunting 87-grain, Hornady SST 95-grain, Berger Classic Hunter 95-grain and a Sierra GameKing SBT 100-grain.

The outfitter who was to host our Kansas adventure, Ted Jaycox (Tall Tine Outfitters), happened to be an old friend, so I’d hunted his properties before. While I bowhunted thicker riverine habitats from treestands, I could not dismiss the greater percentage of habitat consisting of prairie and Conservation Reserve Program (CRP) sprawl. I wanted to be prepared for a long poke if one of the area’s legendary Boone & Crockett contenders appeared across those open environments.

The Nosler Partition 85-grain bullet includes its familiar double-cavity construction with a crossbeam of copper between the dual lead cores to check expansion. The tip expands aggressively to wreak havoc, while the Partition ensures deep penetration even at just 85 grains. The rounded-base softpoint design provided a decent .315 G1 ballistic coefficient. It was paired with Vihtavuori N140, Hodgdon Superformance and Winchester StaBALL. There were no “wow” groups produced by this bullet, but at least one group with each powder was hunt ready. The best N140 group measured 1.12 inches at a quick 3,019 feet per second (fps), the best group with StaBALL 6.5 was an even inch at 3,000 fps. The best group with this bullet measured .97 inch with 46 grains of Superformance, sent at a hard-hitting 3,125 fps.

Berger’s 87-grain VLD Hunting is a scaled-down version of the boat-tail/spear-point 95-grain Berger VLD Hunting, making it suitable to 1:10 rifling twist while still relinquishing an impressive .427 G1 BC. This Berger was paired with Vihtavuori N555, Shooters World Long Rifle and Alliant Reloder 16. This bullet produced the best overall group averages, and at least one exceptional group with each powder. Reloder 16 printed at .61 inch with a maximum load of 41.5 grains, clocking 2,954 fps. N555 produced a sub-½-MOA group with a maximum load of 42 grains and a velocity of 2,899 fps. The tightest group with this bullet measured .41 inch at a respectable 2,979 fps, using 38 grains of Long Rifle.

The Hornady SST 95-grain bullet includes a Super Shock Tip that experience has shown lives up to its name, plus an InterLock ring to ensure reliability on bone. This SST includes a flatbase, which results in a G1 BC of .355. The SST was fueled by Shooters World SW-4350, Hodgdon H-4831sc and Ramshot Hunter. SW-4350 produced a .77-inch group at 2,727 fps using 41 grains of powder, and H-4831sc produced a .66-inch group at 2,787 fps using 42 grains. The hands-down accuracy winner was 41.5 grains of Ramshot Hunter, printing .46 inch at 2,767 fps.

Berger’s 95-grain Classic Hunter includes a shorter hybrid ogive that makes it just compatible with the test rifle’s 1:10 rifling twist, while still providing an excellent .434 G1 BC to minimize drop and especially wind drift on longer shots – and the wind always blows in Kansas! Vihtavuori N560, Accurate 4350 and IMR-4451 Enduron were used with this bullet. N560 produced a .70-inch group at 2,841 fps (43.5 grains of powder) and A-4350 a .73-inch group at 2,699 fps (41 grains of powder). IMR-4451 managed the best group, .64 inch at 2,718 fps, using 38.5 grains of powder.

The Sierra GameKing SBT 100-grain offers an excellent .430 G1 BC and performance I have watched in action enough to trust implicitly. Alliant Reloder 26, IMR-7977 and Winchester StaBALL 6.5 were auditioned. Reloder 26 managed to break an inch with 45.5 grains of power at an astounding 3,007 fps, IMR-7977 printed .69 inch and hit 2,795 fps using 48 grains of powder. StaBALL 6.5 proved the clear winner, producing a .54-inch group (all StaBALL 6.5 groups measuring less than an inch) at 2,811 fps using 41 grains of powder.

The purpose of this exercise, of course, was to discover a load the Mossberg Patriot Predator liked for our upcoming Kansas whitetail hunt. Based entirely on accuracy, my choices included the Berger VLD Hunting 87-grain bullet fueled by 38 grains of Shooters World Long Rifle, Hornady SST 95-grain bullet seated over 41.5 grains of Ramshot Hunter, and Sierra GameKing SBT 100-grain bullet over 41 grains of Winchester StaBALL 6.5.

Running the numbers through Hornady’s Ballistics Calculator, the SST produces 1,336 foot-pounds of kinetic energy at 100 yards and 1,097 foot-pounds at 200 yards – considerably less than both the lighter Berger and heavier Sierra. The SST also drops 4 inches at 200 yards and 14.7 inches at 300 yards – several inches more than the Berger or Sierra. So, the SST was out, though it is a fine bullet hindered in this case by a lack of velocity and lower BC. Interestingly, the 87- and 100-grain slugs run very close for foot-pounds and bullet drop, the heavier bullet, unsurprisingly, edging out the lighter for energy delivery, the lighter edging out the heavier with slightly less drop at 200 and 300 yards.

Ultimately, I will likely go with the Sierra 100-grain bullet and its 1,281 foot-pounds of kinetic energy delivery at 200 yards, and minus 3.7-inch drop at the same range (100-yard zero). It is a bullet I used early in life to tag a dozen desert mule deer. So, like the .243 Winchester cartridge, we have some history, and it is one I have utmost confidence in.