lcq
AH elite
Hi lcq,
I have zero experience with "Core-Lokt Ultra" bullets, nor any of the WSM cartridges whatsoever, and do not even know anyone who has fired either that specific bullet or WSM cartridge, (no matter what bullet brand/model).
However, seems like I read somewhere that your .300 WSM is ballistically quite similar to the .300 H&H.
In which case, I do have quite a bit of hunting and plinking experience with the supremely excellent H&H version - lol.
With it I found the old 180 grain Winchester factory loaded "Silver Tip" bullet was a bit soft but dropped caribou like a stone (they are not very impact resistant and I know of a mature bull being swiftly slain by a wolverine no less, up at Prudhoe Bay Alaska).
"If you weigh over 300 pounds but are easily killed by a 20 pound weasel, you might be a caribou".
Also I have used the old 180 grain Reminton Core-Lokt bullet in the H&H with fine success (also had fine success with this same bullet in the .30-06 as well).
In Africa, I have used the excellent 180 grain Nosler Partition from the .300 H&H and it proved pretty much perfect for Namibian PG.
As for the 7mm Remington magnum, I have only used one bullet/load in that one but it proved very excellent on deer in both Idaho and Alaska as well, for me personally.
It was the old Remington 150 grain Core-Lokt spitzer.
Generally speaking I do not lean toward recent cartridge developments after about the 1930's but the 7mm Remington is an exception for me (as is the .458 Lott).
I like the 7mm Remington magnum for longer range shooting (I prefer the .300 H&H for that a bit more but, the 7mm Remington is my 2nd favorite at the moment).
That being said, I likely would not bring 7mm Magnum to Africa unless hunting medium sized and smaller PG in some wide open place like the SA Eastern Cape / The Karoo, most of Namibia or any similarly open geography/sparse foliage location.
Definitely not a cartridge I would choose for hunting anything in most of Africa (excessive velocity for most of the typical African hunting conditions, including the very likely odds of encountering large/heavy boned game animals at close range).
If however for some unknown reason I changed my philosophy and decided to bring a 7mm magnum to hunt in most of Africa's "normal bush conditions", I would pray that my rifle was acceptably accurate with 175 grain Swift A-Frame bullets.
Not sure how heavy of a projectile your .300 WSM will accept (I presume it has a short action / short magazine box).
But the heaviest .30 A-Frame that rifle will feed properly and shoot accurately, would be hard to beat for most of Africa's so called "Plains Game" hunting conditions.
I presume by the moniker "ultra", that the bullet you have had excellent accuracy with in your WSM is the premium bonded core type.
In which case, please ignore all of my above rant, as you will no doubt have perfect success with it in Africa - lol.
(Too much espresso this morning - sorry).
Cheers,
Velo Dog.
The 300wsm is identical to the 300wm until you get over 180gr. I must say that last May my 7mm with 160 a-frames flattened both an enormous zebra (pass through) and a monster wildebeest (almost through) with a single shot. I used a 150 core-lokt on the bushbuck and there was no blood and no exit, good thing it died quick. The 160gr Ultras would be used in my 7mm which I might add are the same speed as the 180gr 300wsm. I would use 180 accubonds in the 300 and for baboons would use 155gr Amax @3300 with a relatively mild load of 72gr superformance, should flatten them The following link gives an indication of how the Ultras work on gel in a 30 cal
http://www.rifleshootermag.com/ammo/ballistics-test-best-300-win-mag-loads-market/