Out of curiosity, just for thought, would a 300 win mag reamer clean up a 308 norma chamber? I have a 308 norma on a 03, gorgeous gun, but i barely have time to shoot let alone develop loads, and factory ammo for this bad boy is slim. I'm not a 300 win fan but occasionally think it would be nice to buy some factory ammo.

Red

IIRC, the .308 Norma Mag reamer will NOT clean up a .300 Win chamber without setting the barrel back at least a few threads.

As I recall, the Winchester shoulder is considerably farther ahead than that of the .308 Norma Mag. I seem to recall that the .300 Win case is also slightly longer overall, but I may well be mistaken on that part.

I'm pretty sure someone will hop in here with the actual figures, but without looking them up in COW (Cartridges of the World) or some such source, I believe that is, pardon the pun, the case.

AC, I thnk you got the question backwards.

Red, Looking at both case drawings, I think the 300 Winy reamer will clean up a 308 Norma chamber w/o having to set the barrel back.

Yes the 300 winny will clean up the 308 NM without having to set the barrel back but you're not gaining anything. You will probably just have to seat the bullets deeper if the mag box is not long enough. What action is that 308 NM on?

PS I'll take the 308 NM anyday over the 300 Winny.

Not gaining anything? I've never seen a box of .308 Norma at Walmart, and if you do find the ammo at another store, which one do you think will cost you more? Both excellent cartridges but I'd take the .300 WM hands-down any day.

Since the OP states the man doesn't handload, I recommend the 300 as well. In my experience the 308 Mag is a better cartridge, but then again, I roll my own...

Being able to find ammo at WalMart has never sold me on a caliber. However if you are not going to handload the the 300wmag gives you far more options.

308Norma ammo is no more $$ than premium 300wmag but you will have a lot more choices.

What ever you shoot will never be able to tell the difference between them.

If I had a nice custom in 308N I'd leave it alone. But that is me.

I'd leave it as is. Buy some dies, then make a little time to reload and shoot!

quote:

Originally posted by RaySendero:
AC, I thnk you got the question backwards.

Red, Looking at both case drawings, I think the 300 Winy reamer will clean up a 308 Norma chamber w/o having to set the barrel back.

Ray, you are 100% correct. I must be getting some form of dyslexia in my old age. Somehow I read that as asking if a .308 Norma Mag reamer would clean up a .300 Win Mag chamber...

Oh well, thanks for the catch...I guess some days I'm the windshield, and other times I'm the bug....

its a rebarrel it get to 300 win ..
get a 30-06 springfield barrel. and rechamer

harry and i have more or less identical 300 mag springfilds.. his in norma, mine in win... same same, other than ammo doesn't interchange

quote:

Not gaining anything? I've never seen a box of .308 Norma at Walmart

Pardon my mindset. I havn't bought a box of factory ammo in over 30 years except for 22LR.

I think a rechamber to a 300 Weatherby would be more in line instead of a Win Mag, no? It's a belted magnum also but somewhat longer than the Norma.

quote:

Originally posted by finstr:
I think a rechamber to a 300 Weatherby would be more in line instead of a Win Mag, no? It's a belted magnum also but somewhat longer than the Norma.

the bottom metal required would cost more than the rest of the rifle, if you go to weatherby

I had weatherby double radiused shoulder, I was just mulling it over. I have dies, I have brass (A LOT), bullets, everything I need. time, the limited commodity. I guess I have 2.5mo or so though, maybe I'll just take my press with me to the range so I save the multiple 1.5hr round trips.

thanks guys, sometimes it's just good to hear somebody else say your idea is bad.

have a great 4th of July!

Red

I had thsi belief that when the 300 Win Mag was designed it was purposely made so that, in fact, you could take a 308 Norma chambered rifle and, in fact, re-chamber it just by a reamer to 300 Win Mag?

The 300 Win Mag will clean up the 308 Norma chamber.
It will fit in the 03 magazine box as is.
Ammo is somewhat less $$$
However if you figure the cost of having the chamber redone, you can buy 2-3 boxes 308 Norma.
I would just find a source of ammo and shoot the rifle as chambered. I would not spend more $$ to rechamber an already rechambered barrel.

Although the SAAMI overall length of the .300 Win is the same as the .308 Norma and both will fit (just barely) into the 3.35" or so magazine of the Springfield, both are crowded, and especially so the .300 Win, which is .12" longer. I would not want a .300 Win in a magazine that is less than 3.5", particularly if you use some of the heavier, pointy, and necessarily longer bullets like the Accubond or some of the monometals. If you intend to shoot nothing but factory loads, then the .300 will work. But as Duane points out, you'd have to do a lot of shooting to pay for the conversion with the difference in ammunition costs.

The .300 WBY is definately too long for the Springfield magazine.

CHAMBER--not cartridge--dimensions are key here, and, if one compares SAAMI 300 Win Magn with CIP 308 Norma Magn, it will be seen that the shoulder diameter of the 308 Norma is .003" larger (.493") than that of the 300 Win.(.490"). The .493" is measured somewhat closer to the breech face so the chamber body taper would minimize this difference, but there would likely be a remnant of the original 308 Norma shoulder if a 300 Win reamer were run in without setting back the barrel.

Neck diameter of the Norma is also larger (.3465"/.3445") than that of the Winchester (.342"/.3405"). Even though the Norma chamber is shorter and its case mouth falls in the middle of the neck of the Winchester, the larger diameter of the Norma neck would leave a slight step in the middle of the Winchester neck if the barrel weren't set back. Actual manufacturing tolerances of the original chamber and the 300 Win Magn reamer could affect these relationships, but it's still a conversion I'd avoid.

Hope this helps.

Dave Manson