What 7mm magnum cartridge to build?

Idaho Lefty said:

7 PRC is a Sweet choice,.. My son, really Likes, his !
5 shots under, 1/2 MOA with, 180 grain, ELD-M's / ADG Brass at, 2,987 FPS with, "Thrown" Charges of, StaBall HD powder.
7 SAUM is,. another good, choice.
I'd AVOID, the Barrel Burners that, GULP,. Huge Volumes of, Gun Powder !

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That's what I'm wanting to do with this build something a little more efficient

BEFORE Building / Re-Barreling a Rifle, I'd BUY some, GOOD Brass,.. FIRST !
ADG brass,. if, you can Find it, "Works" Good !
Then Dies ( I personally Like, Forster Dies )

7mm Practical (7/300 Win Mag (Peterson Long)
7/300 PRC
7 Max or Mega

I really like my 28 Noslers. 180s at 3200fps out of my 27" Bartlein barrel. I have another one I'll likely use all copper bullets in the 160gr range.

For something a bit different and a very reliable cartridge, how about a 7mm Mashburn Super Magnum?

Kcollins01 said:

That's what I'm wanting to do with this build something a little more efficient

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If that's the route you want, sell or trade the action to a more appropriate action designed for your build.

Frank in the Laurels said:

..based on what we have been seeing over the last 5 years I hain't straying far from cartridges that haven't been around for less than 50 years...a plain Jane ho-hum boring 7mm Remington Mag will handle anything you can hit...with less anxiety than the others..

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I agree I've got 4 of them just wanting something else as well

8twt barrel 26 to 28" long.
7RUM, 28 Nosler, or 7 Rem mag.
Have Fun.

I've had them all, keep going back to a 7 rem mag. With all these new super high bc bullets from Berger and hornady, it takes the rem mag to a whole new level. Get a 8 twist barrel and throat it long. You won't regret it.
Perfect happy medium between barrel life, recoil, ballistic performance and component availability.

Next choice would be a 7mm-300win. Every one of them I've built has been super accurate and easy to find a load for. They will push a 180 to 3150-3175 in a 26" barrel. Quality Brass is readily available as are bushing dies.

My advice,just get the 7mag.When you look at published load data,the 7mag kinda sucks hind tit.That's because it shows data that is often around 58-59k pressure range and it is compared to cartridges loaded at around 63K pressure range.Load the 7mag up to equal pressure,it's a lot better cartridge than what you see on paper.Generally you will be able to get 100-200fps more velocity than what is shown on paper.I have a couple of 7STW's.The velocity gain over my 7mags is maybe 200fps at most,but it takes about ten more grains of powder to get it and the cartridge length starts getting into the mag box limits.With the 2.50" case length on the 7mag built on a long action,Mag box length has never been an issue for me.Cartridges come and go,the 7mag has been around for a long time.It's easy to obtain 7mag brass and factory ammo,so keep that in mind.All my 7mags have 26" barrels.I had one with a 24" barrel that was almost as fast,but I had one that was really slow.So overall,it's just hard to beat the plain Jane 7mag.

Turtle566 said:

For something a bit different and a very reliable cartridge, how about a 7mm Mashburn Super Magnum?

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This would be my choice, hands down! Good brass is easy to come by and I believe it's one of the best 7mm cartridges ever designed.

The 7/300wsm or 7/270wsm (easy button) will get 3100 with a Berger180gr bullet or 2950ish with a Berger195, ADG is supposed to release 270wsm brass soon.

7/6.5PRC (brass is plentiful and tough as a boot) 3000fps is doable with a 180 and some of the hot rod powders.

Kcollins01 said:

Would I have any problems with the saum in a factory 700 bottom metal?

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I believe the 700 Ultra Mag actions have the widest feed lips of any 700 so when going with smaller diameter cases and the stock mag box you need to test what case you intend to use.