8mm necked upto .338 charts?

[rem856]

Anyone have ballistics charts on this round or have this wildcat cartridge.

 

[Mystic Precision]

You might want to be more specific on the case you are working with.


Jerry

 

[NAA]

Anyone have ballistics charts on this round or have this wildcat cartridge.

Wouldn't it be necking up an 8mm case [.323 inch case mouth] to accept a .338 bullet?

Would there be any ballistic advantage to doing this?

 

[John Spartan]

One would wonder how similar a .338x57 would be to the .338-06 and if the small difference in powder capacity would make that much of a difference.

 

[1899]

What if he is talking about an 8mm Rem Mag necked up? Or an 8x68S necked up?

 

[rem856]

sorry, guess i should have clarified. Yes neck 8mm mag casing opened up to accept a .338 bullet.

 

[Why not?]

Essentially, you would have a 340 Weatherby.

Ted

 

[rem856]

Wouldn't it be necking up an 8mm case [.323 inch case mouth] to accept a .338 bullet?

Would there be any ballistic advantage to doing this?

Well this is not my idear, Im simply asking if anyone else has tried or has any info on this cartridge. From what im told less powered, less expensive brass yet same fps from the same bullet. This is just me decidding between .338 rum or this wildcat. Now i saw the targets today from a rifle exactly like i wanna build with this wildcat and at 900 yards he had a 5inch ground. The shooter also took a mule deer at 822 yards confirmed.

 

[AbHobbyist]

Gentlemen,

I would strongly suggest that you chat with Rick of Alberta Tactical Rifle Supply. He has done exactly what you are talking about, but he took it one step further and “Ackley-sized” it, or made it an improved version. I am going by memory, (we have discussed it at length) but I believe that cartridge was blown out with minimal body tapper, and a 35 degree shoulder or so. This cartridge was designed by Rick for extreme accuracy, yet to be assembled from easily available components. While some do not like belts on cartridges, Rick likes them. He had his reamers specially ground to ensure that the cartridge is supported by both the shoulder and the belt.

I myself was some what sceptical, but he proved it to me. At the time I had my custom built, I was looking for a standard cartridge with easily obtainable components and settled on a 7 rem mag, (one of Ricks favourite hunting cartridges). He happen to have a reamer ground to the same way (cartridge supported both on the shoulder and the belt) and lets just say I am very pleased with the results. I hesitate to share results as Im still in load development, but what I have is very promising.

I know he has built at least one rifle and there may be more out there. I myself have been seriously considering this one.

He’s on the board so give him a buzz.

All the best and merry Christmas

R

 

[alberta tactical rifle]

As Mr Wagner posted I did in fact several years ago work on what basically was 358 STA necked to 338 as there are far more bullet options available.
The rifle shot extremely well with 300 gr MKs I was able to get very close to 3000 fps with the 300s and nearly 3100 using 250 gr Gameking btsps.
The advantages I found was that a standard long action could be employed, my own was a Sako AV that was a 375H&H, so length was no issue, mag box was long enough and feed rails , bolt face etc were left original.
Essentially all the same thunder as the newer RUMs but with easy to find brass from MANY makers and easy to find actions with no dickin around to make it work. Dies however were pricey

 

[guntech]

As Mr Wagner posted I did in fact several years ago work on what basically was 358 STA necked to 338 as there are far more bullet options available.
The rifle shot extremely well with 300 gr MKs I was able to get very close to 3000 fps with the 300s and nearly 3100 using 250 gr Gameking btsps.
The advantages I found was that a standard long action could be employed, my own was a Sako AV that was a 375H&H, so length was no issue, mag box was long enough and feed rails , bolt face etc were left original.
Essentially all the same thunder as the newer RUMs but with easy to find brass from MANY makers and easy to find actions with no dickin around to make it work. Dies however were pricey

Hey Rick..... not much different than the .340 Weatherby with a long barrel and the .340 dies are way cheaper....

 

[AbHobbyist]

Guntech:

Its an interesting thought. Out of curiosity, just how long would that barrel have to be to achieve those kind of velocities, with similar bullets.

While it would be difficult to dispute the power of the 340 Weatherby, I am personally not convinced on the long range accuracy of the double radiused shoulder, or the 9 locking lugs that are found on most weatherby rifles. Granted, one could chamber such a cartridge in another action, for example, an older Sako, like the AV, or the 691L, both of which I am partial to. Further I will always listen to an effective and logically laid out argument. So how about it gun tech, convince me this is a good cartridge. I mean this seriously and with all due respect.

For those of you that like Weatherby cases, more power to you, and perhaps an alternative worth considering.

However, for those of us that do not like Weatherby cartridges, this it a great alternative, and a little different.

I look forward to all well thought out responses.

Sincerely

R

 

[alberta tactical rifle]

Dennis , not alot different ballistically than the 340 to be sure, but brass is FAR less costly, powder used is less , dies are more costly , I like wildcats as they tend to be more of a challenge and I DON"T like Weatherby s

 

[Why not?]

Rick,

I don't like Weatherby rifles, however am impressed with a few of the cartridges. The 340 is one and the 270 the other!

Ted

 

[guntech]

Guntech:

Its an interesting thought. Out of curiosity, just how long would that barrel have to be to achieve those kind of velocities, with similar bullets.

While it would be difficult to dispute the power of the 340 Weatherby, I am personally not convinced on the long range accuracy of the double radiused shoulder, or the 9 locking lugs that are found on most weatherby rifles. Granted, one could chamber such a cartridge in another action, for example, an older Sako, like the AV, or the 691L, both of which I am partial to. Further I will always listen to an effective and logically laid out argument. So how about it gun tech, convince me this is a good cartridge. I mean this seriously and with all due respect.

For those of you that like Weatherby cases, more power to you, and perhaps an alternative worth considering.

However, for those of us that do not like Weatherby cartridges, this it a great alternative, and a little different.

I look forward to all well thought out responses.

Sincerely

RW

How I remember the stats concerning the .338's. Hopefully correctly.
I feel if you want a 22 or 24 inch barrel a .338 Winchester will be just fine.
With a 26 inch barrel the .340 is a zinger...about 200 f/s more than the above.
28 and 30 inches are required to get the most out of the Lapua and the .378 cases.... about 200 f/s over the above. (250 grains at 3200 f/s)

I would not try to qualify the accuracy or any other feature of the Mark V action, however the cartridges have proven to be very accurate. The .300 Wby. case was used successfully at 1000 yards, the 6.5 - 300 Wby and the 7mm - 300 Wby..... all very accurate cartridges. The double radius shoulder actually ended up being more of a sales gimmick with no real benefit but it certainly has not been proven to be detrimental to accuracy or anything else.

All require a fairly long magazine box...... the .300 Win. Mag necked to .338 would be a better cartridge in Mausers and other standard length actions.

Remington 700's and most Sakos will work with the .300 Wby. case.

I agree with Rick..... wildcats are fun and I have never owned a Weatherby....