I may soon be the owner of a .300 Winchester Magnum, and have no experience with the round. I will probably use it on elk. From what I've read, either 180 grain or 200 grain bullets are the way to go.

I am interested in both handloads and factory loads. What loads have you guys had success with for elk or similar size game?

Either bullet in a 300WinMag will do the trick.
Pick a good bullet like a NoslerPartition, GrandSlam, FailSafe- etc. a bullet that will mushroom and retain it's weight and not come apart.

My buddy who shoots a 300 Win Mag swears by the Federal Premium 180 grain Nosler partition. It very accurate out of his rifle. He uses it for both elk & mulies.

IVE HAD THE OPPORTUNITY IN THE LAST COUPLE OF YEARS TO DO QUITE A BIT OF
HUNTING WITH THE 300 WIN. 2 SUNDAYS AGO I KILLED MY 1ST IN ALBERTA AND COULDN'T
HAVE BEEN MORE PLEASED WITH MY RIFLE AND LOAD. I USE A 200 GR NOSLER PARTITION
LOADED TO 2950 FPS WITH IMR 7828. THIS LOAD IS ACCURATE, SHOOTS VERY FLAT AND HITS
HARD. I SHOT MY MOOSE RUNNING (HIM, NOT ME) AT ABOUT 100 YARDS. THE FIRST SHOT WAS
PERFECTLY PLACED BEHIND THE SHOULDER BUT I GOT 2 MORE INSURANCE SHOTS THROUGH
THE LUNGS BEFORE THE BULL FELL. THE 2ND & 3RD SHOTS WERE NOT NEEDED. ALL 3 BULLETS
COMPLETELY PENETRATED THE BULL WRECKING THE LUNGS AND EXITING THE OFF SIDE SHOULDER. IVE ALSO KILLED A BULL ELK WITH 180 GRAIN PARTITIONS BUT I FEEL THE EXTRA
BULLET WEIGHT AND SLIGHTLY LOWER VELOCITY GIVES A LITTLE BULLET PERFORMANCE, I'M
STICKING WITH THE 200 GRAIN PARTITIONS FROM NOW ON.

I'm building up a .300 Winchester Magnum for elk hunting here as ranges can change from 20 yards to 350 yards at the drop of a hat. I'm going to be loading up like hotweatherhunter with a stiff 200gr. Partition loading for flat shooting and high energy. Should retain a lot of energy downrange and expand at pretty much any velocity it's bound to hit at. And my Partition experience has been all one shot kills and deep, consistant penetration, so no need to mess with what works.

I have shot everything with the 200 gr. bullets in my 300 H&H and they all worked, I have used Woodleigh,& Nosler, I prefer the 200 to the 180 for elk....

My 300 shoots best and fastest with the 200 grain Speer and H1000. I could not get this rifle to shoot the 200 grain partitions and after $60.00 of them gave up. It puts the Speers into 3/4th's of an inch though and the partition would barely make it into 3 inches.

I've taken three elk, in three years, with 180's in my 300 WinMag. The first was with factory Federal's using the Nosler Partition and the other two factory PMC/ELDORADO's using the Barnes X bullet. No complaints with either. Number's one and three were shot at well over 500 yards and the bullets worked as designed. The 180's shoot flatter then the 200's and that seems to be important if the distance gets long.

I have yet to kill anything with my 300. It is still every bit factory, except I have had the trigger pull reduced from Remington's stiff 8 pound pull to a nice 2.5 pund pull. I have it shooting 3/4 to 1 MOA groups at 100 yards with a 180 grain Partition in front of 75.5 grains of RL 22. It is capable of greater accuracy than I am. And I feel as though it is capable of dropping just about anything.

loud-n-boomer

I use the Swedish Norma Oryx bullet in 200 grains for my 300 win. Mag.

I have three recovered bullets from my hunt in Southafrica this summer.




From left finishing shot for Warthog (5 yards), Only shot for Kudu (300 yards), Heartshot for Oryx (350 yards). Almost no loss of weight at any bullet.

Over here in Africa people use 180 grain bullets most of the time, stay with premium bullets they work fine all of the time

I use (exactly) hotweatherhunter's load for the same reasons MikeyB described and the recommendation of friends who've had spectacular results with them. This time next week, I hope to be able to post an after-action report.

Redial

Sense I started using the 200gr Nosler Partition in my 300 mag. I have killed 4 elk, 3 shot through the chest one the neck. All were one shot kills, and I haven't recovered a bullet yet.