Rechamber 308 Norma Magnum to 300 Win Mag?

[AbitNutz]

I found an orphan rifle built on a '03 Springfield action in a laminated stock. It must have been done a while back when that cartridge was popular and sacrificing '03 Springfields were no big deal. The action is Remington with a serial number in the millions. The barrel is perfect.

Is running a 300 Win Mag reamer all that is required to rechamber it from 308 Norma Magnum to 300 Winchester Magnum? Or is there something else required that I'm not seeing? It's a belted cartridge. The dimentions of the 300 Win Mag are equal to or greater than the 308 Norma pretty much everywhere....all of this work would be done by a genuine gunsmith.


I may ultimately consider returning it to its pre-molested glory but that is not an inexpensive proposition.

[lucifers]

The first question is: "why" ?


It's really an 03A3, sacrificing one is no big deal.

You need to get SAAMI specs on both, chamber cast yours and compare with GREAT care.

Not a bad idea for the cost of a finish reamer BUT brass, dies and loading data for the Norma are no problem.

Also has a much greater "cool factor" than the winnie.

[pietro]

The first question is: "why" ?





I would think that, for someone who doesn't want to reload (there are many such folks who own firearms), .300 Win Mag ammo is more widely available than for the .308 Norma Mag.


.

[knifemaker]

If I remember right, yes you can re-chamber a 308 Norma to 300 Win. mag. using a finish reamer to remove the needed metal. Will give you a rifle where you can find the ammo a lot easier and at a better price.

[AbitNutz]

Let's face it, one of the reasons the rifle is so cheap is because it's chambered in 308 Norma Magnum. I already shoot lots of 300 Win Mag and really don't need ballistically idetical cartridge. Or I could choose to keep it and return the action to its '03 Springfield roots...gives me options I don't have if it's a 308 N/M.

Anyway, that's the way it looks from my end.

[vzerone]

The 308 Norma is a very good cartridge and gives up little to the 300 Win Mag. It has a longer more preferable neck. It's also better suited to the 30-06 receiver. No big deal to form brass for it and if were me I'd just let it be.

[KenT7021]

If work was done to the receiver to make it feed magnum cartridges it may not be possible to go back to the original caliber.

[azrednek]

The 308 Norma is a very good cartridge and gives up little to the 300 Win Mag. It has a longer more preferable neck. It's also better suited to the 30-06 receiver. No big deal to form brass for it and if were me I'd just let it be.

I'm with you. I've been shooting it since the early 70's in a Voere rifle factory chambered for the Norma Mag. Brass can be formed from numerous belted mags but the easiest is with 338 Win. Just simply run the 338 brass through a 308 Norma Mag sizing die.

[crappie-hunter]

I been shootin 338 win mag brass out of a Norma Mag for years it's just a tad bit shorter in the neck after it's fire formed, but my Smith that builds 1000yd bench guns said the only problem you might run into is if you go back to Norma brass, which is longer in the neck,there might be a carbon build up in the chamber just forward of the shorter 338 brass that might have to have a good cleaning with carbon solvent and a brush. This could cause a pressure issue if you force a Norma round in the chamber. No way would I put a reamer in it,if it shoots OK.

[azrednek]

I been shootin 338 win mag brass out of a Norma Mag for years it's just a tad bit shorter in the neck after it's fire formed, but my Smith that builds 1000yd bench guns said the only problem you might run into is if you go back to Norma brass, which is longer in the neck,there might be a carbon build up in the chamber just forward of the shorter 338 brass that might have to have a good cleaning with carbon solvent and a brush. This could cause a pressure issue if you force a Norma round in the chamber. No way would I put a reamer in it,if it shoots OK.

I never ran into that problem but I'm not shooting a thousand yard target rifle. I've found that by the second or third time the 338 neck grows to the same length as the Norma brass. The difference is apx 1/8 to 3/16's at best. At least in my factory chambered rifle. There is a good deal of free bore before the slug engages the rifling and never had a problem.

Have to admit I was tempted to punch it out to 300 after seeing the Norma Ammo at $99.00 per box.

[Texas by God]

Buy it, mark up the price a bit, and offer it on S & S. It may be just what someone is looking for.

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[toallmy]

I have owned at least one 300 win for the last 25-30 years ,.... but consider the 308 Norma the more perfect round at least for the loading and shooting I do . I would have to try her out first .

[bstone5]

Have a 308 Norma Mag rifle. Have had it for a lot of years. The rifle was a 30/06 conversion I got at a good price. Purchased the reloading dies and 100 pieces of new brass when I got the rifle years ago. Shoot ever now and then, an accurate shooting rifle. Back in time there were a lot of the 308 Norma conversions done before the 300 Win came into production. A lot of gunsmiths did the conversions to make a 30 caliber magnum rifle.

[vzerone]

I have owned at least one 300 win for the last 25-30 years ,.... but consider the 308 Norma the more perfect round at least for the loading and shooting I do . I would have to try her out first .

I agree with you and anothe good round is the 358 Norma Magnum.

[lucifers]

I agree with you and anothe good round is the 358 Norma Magnum.

Yes owned both in Schultz and Larsen rifles. Very accurate and would kill any NA game.

[azrednek]

Yes owned both in Schultz and Larsen rifles. Very accurate and would kill any NA game.

A now deceased friend had a very successful business, airplane and the financial means. Traveled all over the Western Hemisphere hunting with his 358 Norma rifle.

[AbitNutz]

I don't get it. Someone took an '03 Springfield and cut it up for the action. The 308 N/M is a great cartridge no doubt but the world is full of great cartridges that are now orphaned and this is one of them. If I can bring the rifle back to some usefulness by having a gunsmith run a 300 Win Mag chamber reamer in it I don't see why this is an issue. It's not like this is some sort of socially signifigant rifle/cartridge combo.

[vzerone]

Did you already purchase this rifle? If so sell it here and use the money for something else???

[lucifers]

I doubt the 03A3 was "cut up". back when that was a popular conversion as there was no 300 WinMag, 03A3s were available and cheap. A little boltface, extractor, magazine rail work, combined with rechambering and you were good to go.

The only alternatives then were a 721 or M 70 in 300 H&H or big bucks for SAKO or Magnum Mauser in 308 Norma or 300 H&H.

Norma and HTM make factory ammo for the 308 NM. If you are just a hunter, buy 5 boxes and you can be planted with some. If you are a handloader, some feel it's a better design than the 300 WM. Components and dies are easily obtained.

Tell you one thing, a SAKO FN or Schultz and Larsen in 308/358 Norma is worth far more than a new 70/700 300 Winmag.


The 308 Norma is not the 22 Velo Dog.

[RustyReel]

If you are a reloader, and I assume you are since you are visiting this forum, then the 308 Norma should not be a problem for you. Easily made from some currently abundant cases and reasonably priced dies come up all the time on Ebay and other auction sites. A Springfield in 308 Norma is a bit of a classic and I see no real reason to convert it to Win Mag.

Just an aside, Simpson's on occasion lists a number of Husqvarna and other Swedish Sporters for sale. The rather uncommon Norma Mags are priced well above the other calibers and you had better call quick when you see one listed.....YMMV

[vzerone]

I doubt the A3)3 was "cut up". back when that was a popular conversion as there was no 300 WinMag, 03A3s were available and cheap. A little boltface, extractor, magazine rail work, combined with rechambering and you were good to go.

The only alternatives then were a 721 or M 70 in 300 H&H or big bucks for SAKO or Magnum Mauser in 308 Norma or 300 H&H.

Norma and HTM make factory ammo for the 308 NM. If you are just a hunter, buy 5 boxes and you can be planted with some. If you are a handloader, some feel it's a better design than the 300 WM. Components and dies are easily obtained.

Tell you one thing, a SAKO FN or Schultz and Larsen in 308/358 Norma is worth far more than a new 70/700 300 Winmag.


The 308 Norma is not the 22 Velo Dog.

I agree with Lucifers. The 308 Norma is actually a better round then the 300 Win Mag in my opinion. That brings to mind the other 7mm Magnum other then the 7mm Remington Magnum and that is the 7x61 Sharpe&Hart which is a better round then the Remington one. It's more efficient. Those big names pushed the 300 Win Mag and the 7mm Remington Mag. An Elk wouldn't know the difference if it was shot with the two "old balls". If you have the rifle already I'd suggest shooting it and see what you think.

[Larry Gibson]

AbitNutz

The 308 Norma was a popular conversion in M1903As "back in the day" for a couple reasons. The primary reason the 308 Norma was more popular was feeding. Many times the 308 Norma would feed from the magazine (both left and right sides) with little or no modification to the receiver feed rails. Most often the longer 300 Win Mag case would not. You might try putting 3 - 4 rounds of 300 Win Mag in the mag and see if they feed.

If the 300 Win Mags do feed you can simply run a 300 Win Mag finish reamer in the 308 Norma chamber to re-chamber. You may end up with a slight "ring" on cases where the shoulder began on the Norma chamber but it will only be cosmetic and won't pose any problems.

[toallmy]

Another thing to consider is , if the 308 Norma chamber is cut properly and it doesn't shoot well it probably won't as a 300 win . But the brass will be cheaper , on second thought it might not be . I think the last time I ordered a 100 new Norma 300 w m casings it they were 90. Bucks .

[vzerone]

AbitNutz

The 308 Norma was a popular conversion in M1903As "back in the day" for a couple reasons. The primary reason the 308 Norma was more popular was feeding. Many times the 308 Norma would feed from the magazine (both left and right sides) with little or no modification to the receiver feed rails. Most often the longer 300 Win Mag case would not. You might try putting 3 - 4 rounds of 300 Win Mag in the mag and see if they feed.

If the 300 Win Mags do feed you can simply run a 300 Win Mag finish reamer in the 308 Norma chamber to re-chamber. You may end up with a slight "ring" on cases where the shoulder began on the Norma chamber but it will only be cosmetic and won't pose any problems.

Larry gave a very good reason why I wouldn't do it.

[azrednek]

I don't get it. Someone took an '03 Springfield and cut it up for the action. The 308 N/M is a great cartridge no doubt but the world is full of great cartridges that are now orphaned and this is one of them. If I can bring the rifle back to some usefulness by having a gunsmith run a 300 Win Mag chamber reamer in it I don't see why this is an issue. It's not like this is some sort of socially signifigant rifle/cartridge combo.

Guess the fondness of the Norma cartridge is from some of us reminiscing of years ago. I once purchased a 1917 Winchester Enfield re cambered to 308 Norma. Got it dirt cheap at a yard sale. I tried to turn a profit with it but it just didn't sell. Had it punched out to 300 Winnie and sold it for a handsome profit.

[wmitty]

Someone please explain to me why the rifle has to be an 03 A3 if it’s a Remington

[Texas by God]

Someone please explain to me why the rifle has to be an 03 A3 if it’s a RemingtonYou're right.Remington made the 1903 along with Springfield and Rock Island. They created the 03A3 and they and Smith Corona were the sole contractors for it.

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[MostlyLeverGuns]

In the 60's (1960's) there was a whole industry dedicated to making 'hunting' rifles out of millions of rifles left-over from WW II. The rifles were not COLLECTIBLES in the 60's, just cheap mail-order surplus, like today's 7.62 Russian's and some Mauser's. Not every rifle has collector value because it is over 50 years old. The 300 Win Mag should be a simple rechamber, with feeding a consideration but careful modification of the feed rails can correct that. The difference between cheap surplus and collectible is what someone is willing to pay. The 1968 Gun Control Act was quietly supported by the American gun makers due to the impact mail-order surplus guns was having their profits.

[lucifers]

Remington made 1903s using the old RIA machines for 3 years. After 3 years the already tired machines were shot and wartime materials issues led to the 03A3.

BUT the OP said the serial # was in the millions. That would indicate an 03A3.

[W.R.Buchanan]

Abitnutz: I would leave it as is, simply because the amount you would actually shoot that gun wouldn't justify the money necessary to convert it. Also there is no significant advantage in ballistics to be gained. It also may not Feed right with the longer rounds so that is extra money you'd have to spend.

You can't convert that action back to .30-06 because the Feed Rails have been ground down to feed the belted cartridge and the bolt face has been altered.

As far as the cost of the brass? Why bother,,, you will probably never wear out 100 Norma cases, so why worry about it.

There is very little advantage to the 300WM over the .308 Norma, other than cost of ammo, and since you would never fire this gun enough for that to be a factor,,, why worry about it.

I recently sold a 03A3 that had been converted to .30 Ackley #1 Short Magnum which is 1/16" shorter than the .308 Norma, which is 1/16" shorter than the .300 WM. The barrel was not marked and it was a real PITA to figure out exactly what caliber it actually was. I figured .300 WM but the bolt wouldn't close. So I found a .308 Norma and guess what the Bolt still wouldn't close! .30 Ackley #1SM was the next stop and Bingo!

With the help of Sal Pal I was able to make cases from .300 H&H cases and get 50+ made and in the box. Loaded them with Cast and 2400 and shot a few of them to verify that gun would go bang.

I sold that gun which was very accurate, to Mike in Peru for his son to hunt the AZ strip with. I doubt he will ever wear out those cases as long as he only neck sizes them.

So again I say why change the gun? It is an excellent hunting rifle. Use it as such.

If I was going to change it I'd be looking at having JES Rebore/Chamber it to .358 Norma.

Randy

[lucifers]

Carnak predicts the rifle will never be changed.

[fast ronnie]

Brass is easily made from 300 Win Mag in one pass then trimmed to length. I just checked on data for these two cartridges tonight and got a surprise. With a 190 or 220 grain bullet, maximum velocity is the same with less powder. Mine is on an Iranian 98 action. Be careful of the loads, though. I use imr 4831 in mine and was using data for H4831. There is a FIVE grain difference in starting loads, and MAXIMUM for h 4831 is less than STARTING loads for imr4831.Don't reduce loads below starting for THIS POWDER as it is not safe. I got mine cheap because of a badly done chambering job and had to replace the barrel. (new Shilen match) Accurate and good for long distances. Back when these were popular, there were many matches won with this round. Unfortunately the 300 win came out 3 years after the Norma, so it never became real popular for any length of time. There are some benefits to this round as it will fit in the Mauser 98 action but the 300 win mag will not. It is a greatly under-valued chambering.

[azrednek]

Brass is easily made from 300 Win Mag in one pass then trimmed to length. I just checked on data for these two cartridges tonight and got a surprise. With a 190 or 220 grain bullet, maximum velocity is the same with less powder.

When Winchester introduced the longer and more powder capacity 300 Mag. The velocity of the 300 only exceeded the Norma by less than 100 FPS. The larger charge of Winchester powder was not as efficient as the Swedish manufactured Norma powder.

BTW, I found it easier to run 338 Mag brass through my Norma sizing die. It is usually 1/16 to 3/16 short but no trimming. By the 2nd or 3rd firing the brass has flowed to take up the gap,

I have a Voere rifle factory chambered for 308 Norma. Simply no way I'd ever consider punching it out to 300 as long as I can handload my own ammo. Be a cold day in heck though I'd ever pay $120.00 for a box of 308 Norma Mag factory ammo.

Wasn't that many years later after chronys became affordable. Winchester, Remington and Federal were caught with their pants down exaggerating their velocity. Tests of Norma's ammo revealed they were squeaky clean in their velocity claims. Most of the exaggerated claims were handgun ammo, 357 in particular. I've often wondered if Winchester didn't exaggerate the velocity of the 300 to exceed the 308 Norma.

Something about the 308 Norma Mag forgotten to history. It was officially adopted by the FBI for their first long range snipers. I got it confirmed during a tour of the FBI's office in Wash DC. I asked the agent doing the shooting demo. Unfortunately he didn't recall what kind of rifle.