Best short mag cartridge for elk?

What short mag would you build and why?

Use: lightweight mountain rifle that's capable of handling elk out to 600yds or so.

I do reload so everything is on the table. Minimum bullet weight of 150gr

Must work well with a short barrel, probably 22" but may go 24" if I have to.

I've considered 7saum / 7WSM / 7x300 WSM / 300 WSM

If it's a dedicated elk rifle, the .325 WSM seems an obvious choice. If you want the most available factory ammo, then .300 WSM. If you are into the esoterica of cartridge design, then perhaps a 7mm SAUM. All that out of the way, why not just get a .284 Winchester?

If I were building it would be 300 RCM or 300 WSM

I'll vote 300 WSM, but it's beyond my capability.

I wouldn’t build a short mag for that, but since you asked, I’d go with the .300, to kill elk at 600.

of the short mags I would go with the 300 or 323 for that but really wanting to go 600 for slk I would go with a long action cartridge

The 7x300 WSM would not be my choice as it has a tad less powder capacity than the 7mm WSM. They extended the case body a fraction on the 7mm WSM to keep it from chambering and firing in a 270 WSM

I've killed 2 big New Mexico bulls with 270 WSM.

7mm08

last I checked that's not a mag cartridge...but I like your choice.

6.5 SAUM and 147's (Tony killed a cow a few weels ago at 515 yards)

7 SAUM and 180's

There's only one short magnum that's got my attention and that's the 270 WSM. It's the only one that doesn't just duplicate what's already available (270 Weatherby excluded). Run a 140 Nosler Partition at 3250 or a 150 at at 3150 and you have some serious Elk medicine. Mrs. B will be shooting a 270 WSM in the future.

Any of them would work fine, so it’s really just personal preference. I like a larger bullet for elk, so my personal mountain rifle for bigger game is a .300 WSM.

I shoot 180 grain bullets.

338 WSM. It's a 300 WSM (or 325 WSM) necked up to .338". I have built 2 of these rifles. The last one we just finished. We are pushing a 250 grain Berger Elite Hunter at 2702 fps in a 22" barrel. Making brass is super easy. Just run 325 WSM brass over a 338 expander ball, and done. Or, neck up 300 WSM with an 8mm expander (.323") then a .338". It's very easy to make.

A little bit about the 325 WSM cartridge. It has the best "gas mileage" of any round. Meaning, it can push the heaviest bullet the fastest with the least amount of powder. The 338 WSM is right in line with it also, being only .015" larger, with much better bullet choices.

The 6.5 SAUM (or 6.5 GAP 4S, same thing) that Tony built pushing 147 ELD bullets is pretty nice, also! Very flat shooting with a high BC. That would be a good one, also.

I shot a 1400 pound cow with a 300 Wsm. Dropped like it had been hit with a sledge hammer.

Shot two elk earlier this season with my 6.5 SAUM4s with the 143 ELD with good results.... both were only 175 yds though. I stumbled onto a lefty 270 WSM Tikka and with a 145 ELD-X loaded to 3180 that thing shoots amazing so I don’t doubt it’s capability.

I love the .270 WSM. It might just be the perfect sheep cartridge.

The purpose of the short mags was not to improve upon the performance of the parent cartridges, it was to duplicate them in a short action to facilitate weight savings in mountain rifles.
The added 150-200 fps the .270 WSM provides over the .270 Win was just a happy by-product of the different case configuration in that round.
With the exception of the .270 WSM, shooting the other short mags in non-lightweight rifles serves no real purpose.

Any of those you listed will work. I have killed elk with 300 WM and 300 WSM and both worked well. I am of the same belief as Chad with regards to the 338WSM. I will have my 300 WSM re-barreled to 338 if I ever need something bigger.

I agree that the .338 is probably the best elk round going too.

Recoil can be an issue with lightweight mountain rifles, so there’s always that to think about. If I wanted to step up from my .300 WSM, I would probably just get a .325 WSM and call it good.

Couple of these listed I wasn't even aware of. I'll Have to do a little research on them. I am a little concerned about the recoil as it is lightweight rifle. I guess I could always add a titanium brake and calm it down a bit.

I had a 7mm WSM built to run 180s to be my everyday gun but still be able to chase elk with it. 1-8 twist 24" brux and currently running on my lower node at around 2850. Without my can it kicks about like my dads 7mag, but with it, its about like a .243. With the can it feels about 8 foot long unfortunately, so the next bang stick will have a little short barrel.

I'm found of my .300 WSM and staring at an elk and mule deer on my wall courtesy of that gun...

6.5 saum or 270wsm would be my picks

[size:11pt][/size].270 WSM, .300 WSM in a short magnum. However my best elk/mule deer rifle is a custom Remington 700 in .300 Weatherby, 180 gr. Sierra JSP and 180 gr. Barnes X (original X bullet). Longest shot on a bull elk just over 500 yds. one shot, took two steps DRT. Sitting from a solid tree limb rest.

What ever you shoot best at 1000 yards

Like thwy said, i went with a 6.5 suam, carbon fiber stock and carbon wrapped barrel. Having just had spine surgery recoil was a concern. And after running the numbers found that a 147 with its high bc and speed only gave up less than 80 pounds of energy at a 1000 yards compared to the 180 7mm i typically run in the mountains. And nothing in a short mag platform can hang with it in the wind department, and switching winds up there can be a problem. Ended up taking a cow at 560 yards and got it all on video through a swaro spotting scope with a camera attached. She folded like something flipped her main breaker. All of them will get it done, but none with less recoil and less wind drift. Just my 2c, and what I did,

I'd do a 338 RCM...works great out of a 20-22 inch barrel...if a dedicated elk rifle nothing hits a big bull like a 338. You can push225s- 250s at reasonable velocities, and with the 338s decent BCs if you need to reach out there no problem. Just my two cents...

The 338 RCM is a little smaller cartridge than the WSM case. It holds about 5-6 grains less powder capacity, has the optimum 30 degree shoulder angle, and is about .100" shorter than the WSM case. If you wanted a true short action round, the RCM would be it. If you have a long action, the 338 WSM would be good. I started load work up on the 338 WSM as a short action in a short mag box, but the 250 grain wouldn't fit. So, we went long action, seated the bullet out much further and gained a lot more powder capacity for higher speeds. 2702 fps with a 250 Berger in a 22" barrel is nice! I really want to build me a 338 WSM on a Tikka, which is a long action action, and fits nicely in it. Put it on a Proof barrel, and that would make a great light weight, magnum rifle!

that is a BIG cow, bigger that lots of bulls

Actually bigger than every bull on the planet.

A bovine cow can get heavier than that. He may be talking bovine.

I've been tempted to try mine out on bovine the last couple weeks.

Ive been tempted many times but never gave in

7mm WSM Creedmoor Ackley Improved

I don’t know what else he could be talking about. I assumed bovine when he said it.

I was automatically thinking cow elk. Shooting an actual cow didn’t enter my mind. Y’all are almost certainly right.

Who has ever hunted on a deer lease and not wanted to shoot a cow or two?

WELL everyone was talking about ELK, so i thought he was too.
1400 lb is a big bovine cow also

Wrong post

You should try Berger Ballistic Tips. They shoot 600 yards with no drop at all.

270 wsm or 300 wsm would be great. I have both and took my cow bison with a 165 gr A Frame last Jan. One shot kill. My last moose was taken with a 270 wsm 140 gr bullet.

No need to shoot out to 600 for elk, get closer.

Sorry, black angus, cancer eye with maggots.

Same, 300wsm and she has taken several Elk, most with one round using factory Rem scirroco 180grn.

Have also taken many with a 7mm as well, also using 180grn factory ammo, imo both are better at range than most shooters behind the wheel and both definitely will put down an elk.

7 WSM. I agree with what has been stated that they will all work. I will be the odd man out and say I choose the 7 wsm. The 30's and 7's have a lot more available in the way of projectiles over the 270 wsm and I really like the way the 7's fly. And yeah I already know that I may need to size 300 wsm brass and fire form it to 7 wsm dimensions. In my opinion it is also the most capable of the wsm's at distance.
Sounds like a fun project

6.5 Creedmore Magnum.

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300 Rem. Short Action Ultra mag!

I’d personally go with the 300WSM.