Thoughts on a 7x300 wm?

Anyone built one? Is it worth it? Looking for something with a little more umpf than the 7mag. And I love my 7mag.
I've been running the 7 Mashburn Super for 3 decades. A wildcat from the 50's/60's. I use 300 WM cases as a base.

For me it's worth it as I get the speeds I like without pounding the dog poop out of the cases/gun etc.

IMO it's a heck or a round and gives me what I want in a long range kill on demand kind of round.

Side note, I've gone thru multiple barrels, round count is generally in the 2K-2500 range. For something that I'm running 71 grains of powder thru with a 150 NBT I'm quite happy with this round count.

Normally around 1700 rounds the barrel begins to foul a bit, and shortly after I chase the lands a bit until I give up the ghost with it. (side note, I detest cleaning barrels and for darn sure barrels that foul...)
 
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..unless you got a stack of .284 barrels I'd stear clear of this one..seems like a bit much powder to be burned for very little gain in a hunting length barrel...but if you got some extra $$$$ laying around, have at it....buy an extra set of muffs, I sat next to a guy during a benchrest competition and my ears rang for 6 months while wearing muffs and ear plugs..loudest cartridge I ever heard..
 
If you have the option I would have a 26” barrel for it.
I have wanted one for a while now and just haven’t been able to get it done.
I ended going the next step up with the 7STW which I love.
I love my 7RM’s as well but the STW is a beast
 
I've been running the 7 Mashburn Super for 3 decades. A wildcat from the 50's/60's. I use 300 WM cases as a base.

For me it's worth it as I get the speeds I like without pounding the dog poop out of the cases/gun etc.

IMO it's a heck or a round and gives me what I want in a long range kill on demand kind of round.

Side note, I've gone thru multiple barrels, round count is generally in the 2K-2500 range. For something that I'm running 71 grains of powder thru with a 150 NBT I'm quite happy with this round count.

Normally around 1700 rounds the barrel begins to foul a bit, and shortly after I chase the lands a bit until I give up the ghost with it. (side note, I detest cleaning barrels and for darn sure barrels that foul...)
Do you know what kind of speeds you are getting with 150’s?
 
Nathan Foster is a fan of the 7-300 win which he has dubbed the “7mm Practical”. His “ballisticstudies.com” website has a fair bit of info and relaying of his experience with it on there. He is a wealth of information about all things regarding terminal ballistics, some of the info is a bit dated at this point and of course I don’t agree with every single thing the guy says but I greatly respect his vast experience and knowledge.

He feels it’s kind of a sweet spot ballistically, genuinely outperforming the 7 rem mag and getting within 50-100 fps of the 28 Nosler and 7 stw with notably better barrel life and efficiency out of normal 26 inch barrels. The 7 RUM is entirely in the realm of diminishing returns, and out of hunting type rifle barrel lengths the 7stw and 28 nos have dipped their toes into that diminishing return/disproportionate barrel wear territory a bit as well in a way that the 7-300 win mag (and 7-300 prc) actually do avoid.

Again, his opinion based on lots of experience with all those cartridges, not mine. Just throwing it out there.
 
Deff build that 7-300!! Obviously everything is personal preference but i think it's bad arse. My beliefs are in line with Nathan Foster's on it being a sweet spot. Out run the 7mag but not outrageous like the 28. Not knocking the 28 at all but is the extra 100fps really worth only about 500-600 shots before it's toast? If the gap was from 2900fps to 3000fps I'd say maybe. But the gap is more like 3100fps in the 7-300 vs 3200fps in the 28 (nominal numbers). The 7-300 is plenty fast IMO and you won't be needing to rebarrel it after your 3rd range session.😁😁
 
To be perfectly honest, the 7-300WM is fantastic and very accurate to boot, but for me, the 7STW pushes all the right buttons and is a truer step up from the 7RM.
The only drawback to both/either, is the fact you need a true magnum length action for them to really shine, a standard length is too short in OAL for them to gain anything over the 7RM.

Cheers.
 
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