Help me choose a caliber

264Magnum

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Dec 18, 2012
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I just came into a Winchester M70 LA in 7mm Remington mag, and want to rebarrel it into something with more punch. I originally was going to just go with a .300 Winchester, but I'm thinking something bigger than that would be fun. I'm not a long range shooter by any means, but the skill is very intriguing to me and that's what I'd like to get into with this rifle. The two I'm thinking about are the .338 Norma and .330 Dakota, if brass is even available since Dakota went kaput.

Are either of those viable options? Is there a different cartridge I should consider? Or should I just be boring and uninspired and go with the original idea of a .300 Winchester?
 
I would never go from a 7mm to .30 Cal. What do you mean by "more punch"? More energy? There is 175+ grain bullets available for 7mm while also getting the higher BC's to go with. The 7mm Remington Mag is plenty of rifle for most any mamal. Does said rifle shoot? Is a rebarrel needed? -personal rant over-

If you just have to change it up,skip the 30's, take a long look at the 7mm STW. A awesome round to say the least. If that just isn't enough go to .338. Ballisticly speaking you'd be better off. Maybe .338 edge?
 
I'll add some more info. I already own two .264 Winchesters and a 7mm Remington mag, I bought this newest 7mm specifically to be a donor action to rebarrel into something bigger.

Its a matter of want over need. I don't "need" a .338 anything, but I really want one. And since it'll get a new barrel and new stock, I may as well build it into more of a long range rifle.
 
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Rule number in caliber selection. If you want more poop, you get a bigger bore. Equal case dimensions and other factors such as barrel length and tolerances being equal bigger always has more potential. That said, there are few free lunches in this game and you will always pay a price somewhere for whatever you decide. Bullet weight and form factor being equal, smaller always wins while bigger has more potential with higher weight and subsequent BC. The down side to going bigger is heavier recoil.

If you have a 6.5 rem mag and 7mm rem mag the next step is a 300 win mag. Neither can match the energy or wind drift of the 300 but you will pay for it in the recoil isle.

338 Norma is sexy but expensive and harsh. This will depend on how far you want to hit what. Or maybe you just want a fun toy to hammer steel with and that's cool too.

In the end, it all boils down to what floats your boat.
 
I'm not recoil shy at all, so that isn't a factor.

The thing is, I don't know what floats my boat in this field. That's where you guys come in. I've been poking around the internet, and the .338 Norma does seem awfully expensive to play with, so I guess that's out. My main concern after cost is simply whether the Model 70 action and mag box is long enough to handle some of the bigger cartridges out there.

Realistically, would the .338 RUM sort of be a good median round for cost and performance? Assuming it'll fit the action.
 
So I need to quit over-thinking it and just get a .300 with a good scope and a good load and learn how to use it?
 
As a.264 Win Mag fan also my big caliber is a 300 H&H & I would hunt anything in North America with it period. As for long range it's the nut behind the butt that counts. One can not buy it you have to do it. Good Shooting.
 
Go with the 300 Win Mag if $ is the deciding factor, 7mm STW Rem brass is scarce and so is the parent 8mm Rem brass.... the Nosler stuff is a lot more $$, other than that the 7mm STW shines with light bullets at mid range on mid sized game but has nothing over the 300 Win Mag in killing performance on big game

I would suggest the 300 Norma Mag for a bit more $ over the 300 Win, Norma brass is spendy at $49.49 per 25 pcs but still less then the Nosler (Norma made) 7mm STW brass at $67.99 per 25 pcs. (Midway)

My opinion ?
0ut of the 3 mentioned, the 300 Norma Mag is by far the sexiest and coolest girl on the scene, It is time to retire them old worn out gals..... sure you can give them a facelift via a longer bbl and put some makeup on via high bc Bergers... but the facts are .... their time is up.................................

and don't forget.......the 300 Norma Mag does not have a spare tire around her waist !
 
One thing to take into account when considering a cartridge like .338 Norma is the case head diameter. It uses a case head similar in size to the .338 Lapua, which is significantly larger than a belted magnum case head or a RUM case head. While it can physically be made to fit, there has been debate about whether or not it leaves enough metal in the tenon area of a conventional off-the-shelf action.

Both Remington and Savage have shoehorned the .338 Lapua into their actions and offer them as factory chamberings. While ostensibly not presenting a safety issue, the Savage in particular, has had some issues that call into question whether a standard sized action is really the right choice for that class of cartridge.

A Winchester model 70 has a shorter magazine than other popular actions such as the Remington 700. If you plan to load long, sleek VLD's of any kind, you should strongly consider having a Wyatt's extended mag box installed, which will allow OAL's of up to 3.850.

If you want to go with a big .338, I think your best choice for a standard factory action is something based on the RUM case. Even so, I would expect some work would be required to make it feed properly.

Overall, however, I believe chambering your rifle for .300 WM and setting it up to take advantage of the .30 cal heavies like the 208 AMAX, 215 Berger Hybrid, and 230 Berger Hybrid would be a surer bet. You won't quite have the punch of the big .338's, but you will have similar reach.

I am in the process of doing something similar with a Mark X, but I don't have the option of going with an extended mag box. It's not a big deal to me, but the advantage in that scenario definitely goes to the Winchester Model 70.
 
I just came into a Winchester M70 LA in 7mm Remington mag, and want to rebarrel it into something with more punch. I originally was going to just go with a .300 Winchester, but I'm thinking something bigger than that would be fun. I'm not a long range shooter by any means, but the skill is very intriguing to me and that's what I'd like to get into with this rifle. The two I'm thinking about are the .338 Norma and .330 Dakota, if brass is even available since Dakota went kaput.

Are either of those viable options? Is there a different cartridge I should consider? Or should I just be boring and uninspired and go with the original idea of a .300 Winchester?

Look into the .300 Ackley Magnum. It's an improved .300 Weatherby. I think you'll find it might be what your looking for.

And the 7mm STW with 180 Hybrids is one nasty LR setup. There are guys accurately shooting them to a mile, maybe farther by now...
 
I just came into a Winchester M70 LA in 7mm Remington mag, and want to rebarrel it into something with more punch. I originally was going to just go with a .300 Winchester, but I'm thinking something bigger than that would be fun. I'm not a long range shooter by any means, but the skill is very intriguing to me and that's what I'd like to get into with this rifle. The two I'm thinking about are the .338 Norma and .330 Dakota, if brass is even available since Dakota went kaput.

Are either of those viable options? Is there a different cartridge I should consider? Or should I just be boring and uninspired and go with the original idea of a .300 Winchester?
Of course if it shoots, IMO don't mess with it.

but

Depending on your intended use, a 308 or 338 call, nothing new there but I have to state it as part of the narrative.

Chamberings with "more punch" that should fit the bolt face and action:
338/300 WinMag (Improved or Not)
338/26 Nosler (I am biased)
338 WinMag (Improved or Not)

300 WinMag (Improved or Not)
300/26 Nosler
300/338 WinMag, aka 300/7RM (Improved or Not)

There are many many more chamberings. If It Were Me (IIWM), of course it would be the 338/26 Nosler but the 338 WinMag is a hoot to shoot and forgiving in load development (well mine is)

If you need factory ammo availability, IMO, it drops the list to just 2, 300 WinMag or 338 WinMag.
 
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