338Mag or 8mmMag opinions wanted.

Gunny K

New member
Back about 15 years ago, I wanted to build a 338Mag that had more Umph than the 338WinMag. At that time I was into using the 8mmRemMag case for all of my projects. I built the 7mmSTW, I necked one to 30cal, Idid one in 375JRS and I was next planing to fill the gap with one necked to 338. Since than, I never finished the 338 project but I have a beautiful 26" barrel that is unchambered in that caliber. Since than there are many new Mags in that caliber but I do not want to, Change the bolt head size from the Belted Mag size and I do not want any more recoil than the belted magnums provide. The RUMs I read are quite brutal. Since than I also started shooting quite few 8x57 Mausers which I did not shoot at the time. So, If I just neck to something like the 338 Jerrett, I have another wildcat which I can't buy off the shelf ammo for or since I already have a plethora of 8mm reloading supplies, should I just stick to the 8mmRemMag which I did not even consider at the time when I ordered my barrel. It is easy to sell an unchamered barrel and just buy a new barrel and call it quits. The bullet size is only .015" and today there are quite a bit more bullet selections in 8mm than there were 15 years ago. What do you guys think. Obviously I will make up my own mind but would like to get some input to help me do so.
 
OK, but why? At this point I will need to get another caliber in bullets which I do not load in and wind up with a wildcat. Justify the 338 please.
 
I have been an 8 fan since the early 60s, so you know what I would choose. Only draw back for me is generally I don't like screwing around with belted cases although I do have a few rifles chambered for such.

The 8 mag is a heck of a cartridge, always has been. What happened to is is at the time it was introduced, there were no bullets available that could use its velocities. As you stated, things are much better now.

It is a very accurate long range cartridge, and I think you would pleased with it as your project's cartridge of choice.
 
Why .323 when you can have a .338? Lots better bullet selection with the .338.

Deaf

.015 is four sheets of paper. Personally I like both calibers also, but there are advantages and disadvantages to each. Just to clarify, I want to stick to the 8mmRemMag parent case in all cases. No RUMs, Lapuas, Rigbys or anything else. The 375 H&H Belted Mag must be the parent case under all circumstances. And I forgot in my initial list of calibers i did with the case was the 450 Ackley.
 
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At this time, in my rifle collection of 30 or so rifles, I have NO .338 calibers. I have 223, 243, 280, 308, 323, 375 and 458.
 
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I used to have an 8mm Rem Mag. Great gun, shot flat as a string. The biggest problem with the cartridge was that once Hornady discontinued their 220 gr Spire Point, there were no bullets designed for the kind of velocity people were generating without going to RWS bullets designed for the 8X68S (and they were expensive as well as hard to get). The 150-200 gr bullets available were all for 8X57 velocities, about 25-30% lower than the 8mm Rem Mag. Also, powders available then were not as slow as the powders available now, so velocities were lower at higher pressures. I believe that if Retumbo or similar powders had been available in 1980, the 8mm Rem Mag would have been a hit with an extra 10% gain in velocities.

As to your question, Gunny, the situation has changed a lot as far as powders goes, but the heaviest bullets available for the 8mm are 220 gr (Sierra GK and Swift A-Frame). So, if I were to recommend either a 8mm or a 338, I would go with the 338 simply for the bullet construction available in that caliber. I would also recommend stepping up to a non-belted case like the RUM case, but you said that was a no-go.
 
I have used the 220 gr Woodleigh, 256 gr Cutting Edge, 220 gr Sierra to name a few and had very good results in the 8 RemMag.
 
If I need something that moves a heavier bullet, I will go to the 375JRS. So I am looking for something in the intermediate weight group. Same as I shoot the 308 calibers only up to 160gr and the 7mms only to 140gr, 6mms only to 100gr and so forth. The 375 I shoot starting at 235gr to 300gr and so forth. Each caliber I either have in the full length belted magnum, 308 case or the ? x 57 case. The small stuff I have a few oddball cases such as the 6mm-284 and also 6mm-264Mag. My favorite is mmy, what I call .375 American T.R. which is a shortened 338 Mag case down to 59mms length. That is my 375 lightweight which is a ballistic equivalent to the 376 Steyr and I can actually chamber the Steyr cartridge in a pinch.
 
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Sounds like you just want an 8mm rifle. Nothing wrong with that, but from a practical perspective there are better choices. It is so close to 30 caliber that I'd not waste my time with 8mm. Personally if something in 30 caliber wouldn't get the job done I'd skip right over 32, 33, 35 and 36 caliber options and go straight to 375 mag.

Any of the 30 caliber's with similar bullet weights and cartridge capacity will do anything an 8mm will do. And do it with less recoil.

There are so many better bullet options in 338 too. If I compare an 8mm 200 gr Nosler Accubonds to a 338 WM with a 225 gr Accubond the 338 has over 400 more ft lbs energy at 400 yards than the 8mm with drops within 1/2". And the 8mm has a 100 fps advantage at the muzzle. BTW, just for reference, a 300 WM shooting a 200 gr bullet will match 8mm/200gr at 400 yards even though it starts the same bullet weight 250 fps SLOWER.

Bullets with good BC's do that, and 8mm has none.

Of course there is no rule saying anyone has to hunt with the most efficient and effective rifle. We hunt for fun and if you enjoy using a particular rifle, then use it.
 
I have a 6mm-284. That is because the 284 Win was designed as a cartridge with the same capacity as the 30-06 for a short action. So an 8mm-284 would be the equal of 8mm-06 This in fact is an insignificant step up from the original 8x57, which I have 7 of in various configurations, civil and military. I just recently (within the last couple of years) really got hooked on the 8mm-Mauser. Got a pig with one two years ago. I consider these type of cartridges as "short range" and only have Williams peep sights on them. I consider anything which I would use for 300M or less as short range. I'm still used to qualifying at 500 yards with iron sights and most likely this will never change with me.
 
Bullets with good BC's do that, and 8mm has none.

The Cutting Edge 256 gr MTH has a G1 BC = .750

The 225 Gr = .640

I would say that is respectable and much better than "none".
 
I figure you can pursue your preferences for your own reasons.I won't ask you to justify them.
You ask the question "Which fork in the road?"
A gentleman recommends the .338,and you ask him to justify it.
I run short of patience when someone asks for advice,then argues.
Fill out your chart any way you want to.Do whatever makes you happy.
IMO,before you make a tool,the tool is defined by its purpose.
To what purpose will you build this rifle?
You seem to cut your bullets off at a fairly light for caliber place.I built a30-338 that launches 200 gr Accubonds at 2900fps.At elk hunting altitude,it has 2000 fps+ at 700 yds. That's pretty much like a 30-40 Krag at 100 yds.
I wouldn't shoot at an elk that far,but what is it that on that class of game I cannot do?
8mm is just a number.Its a fine number!!. In contemporary times,how much projectile development has occurred with the 8mm?
Contrast that with the development that has occurred via military applications of the 338 Lapua. Get up into the 270 to 300 gr bullets in 338 and they fly.
Incredible BC'sare available,and extreme accuracy bullets.

Bigger,tougher targets? from .308 to .323 is a romping .015 in. Just under 1/64. Way less than 0.5 mm. If you have a 30,what is the point?

I'm thinkin 30,338,and 375 cover the steps.Lots of bullet choices.

And,military applications aside,the bigger and tougher the target,the less likely I'd take a long shot. What can't be done with a .375 H+H?

Long range? Look what gets done with the Lapua. The 338 RUM has Lapua ballistics.Therewas,for awhile,a 416 Rem Mag,a necked up 8 mm Rem.If you like that brass,neck to 338.
Just my opinion. Have fun
 
I am not looking for Justification, just looking for more than a four word response. Such as your response, which is very good. No need to get defensive about it. I figured this would be a thread of opinions. No more no less. Why do some guys like blonds and some ravens? Myself, even though I am blue eyed and blond, prefer ravens :) . But I also do not smoke or drink. But at the age of 58 still ride motorcycles at speeds well above 120MPH, I have 7 of them and they are all Kawasaki ranging from 1974-1984. I build my own bikes also, all using Kawasaki engines over 1L in the same timeframe. Why would a Czech Emigrant like myself join the Marines at the age of eighteen and spend his life there? Because I could. I drive Cars that start with the letter "J" and would never buy a German, Japanese or Korean car or a Ford. I will never forgive the Germans for what they did in Czechoslovakia but I can and did forgive the Russians. When I fly, I ask weather the flight is a Boeing or an Airbus, because I will not fly on an Airbus. I prefer the 8x57 over the 30-06 in calibers but like the Vz-24 just as much as the 03-A3. But yet I prefer the 7mm-08 over the 7 x57. Why? Just because that's the way I am, and this great country I adopted and got accepted in, allows me to do so. Why do I need another rifle, in any caliber, just because I want one and I can build it myself (mostly, I don't have the facilities for bluing). Put that in your pipe and smoke it. Why did I mention all of this? Just because to give people more to hate me for. LOL :) I just don't like short unjustified answers. I like Full, Meaningful, conversations. I like to argue just for the sport of it, too.
 
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Well.its not guns,but my first scooter was a Montessa,then a CZ,then a Maico,Then a Triumph T-150 V opened to960cc.All I have now is a Yamaha TT 500
But back to guns.
I agree,its a venue to exercise preference.
You might be quirky enough for a 9.3 mm.
My .375 is aChatfield-Taylor.I neck a 458. 1952 FN commercial Mauser action.
Pretty much a 308 trajectory.I'm not sure I have open space enough to justify a 338 Lapua these days.
I work backwards from the target/job. I pick a projectile.I pick a velocity.Calculate trajectories. Decide how far I want to walk with it.

Have fun!!Do it your way.
 
Do some home work on the 340 Weatherby, have used one for the past 27 years in Alaska and Africa. Mainly use the 225 gr Nosler part.at 3100 fpm in my rifle and crony. Almost equals the Lapua and you can easy have the barrel rechambered.
It hits hard and two of the PHs I hunted with said " You could use that on Cape buffalo"
My first two hunts in Africa wee for plains game and I took a 300 Weatherby and the 340, both rifles built on Remington actions.
The 340 was dramatic in the difference on game from Steinbok to common eland.
Also some heavy animals in Alaska.
I went down the same road you are on as to the Rem 8mm back in 1990. The years of hunting since 1990 have proved out my assumptions in choosing the 340.
By the way I have had 2 338s and they did the job. Based on Kodiak Is. deer hunts. The 340 with its 150 to 200 fpm additional vel. Is a better choice.
 
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