Help me buld a big .338......

Marine sniper

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Washington State.
After a lot of thought and research I am going to build one of the various .338's. I have spent a couple of hours running ballistics on JBM, thinking about what level of performance I want, quality of brass, inherent accuracy etc, etc.

I was strongly leaning towards the 338 Allen. I love all that power and as a drag racer I love horsepower !! However, at this time I am thinking I am going to go with something with a little better barrel life. I want something with more power than a 338 Lapua. I have a 300 Wby and 30-78 Wby, and don't think the Lapua can out do the 30-378 by enough (if at all) to justify it. So...... I am thinking 338-378 Wby. Here is why ) I am open to suggestions on other .338 cartridges !!

I think with a 32 in barrel I can get 3000 fps with a 300 Berger or SMK
The brass and precision dies are very available.
It is a proven caliber

I am looking for recommendations on barrels and actions. I am leaning towards a Hall action with a Shilen barrel. Also looking for a gunsmith with a turn neck 338-378 Wby reamer. I am not interested in a standard chambering.

I am all ears to those with experience with the 338's

Ideas ?

John
 
I have the 338 AM and have never regreted it. Why not go for the best right out of the gate? I did. Not that much more $$$ and you have that top fuel dragster that you wanted.
I know, I didn't help much, sorry!
 
I shoot the 338 Slowpoke (based on a 338 Lapua) in several rifles for hunting and in competition. In the latest hunting rifle used for ELK hunting the 2 weeks that I had to work up loads got the 250gr SMK to 3049 without excessive pressure signs and up to 3179 WITH a hard to open bolt!! The 3049 load shoots .4 at 300 with no brake and let me tell you it jumps 4 inches off my front rest. Rifle and scope weigh 11.2 lbs -- knew I should have not loaded that much WMR and H1000 on the over pressure loads!!!!!

Anyway I will be glad to send you the print of the cartridge to look at if you are interested. Speedy helped me with this and we got Kiff to build the reamers to chamber with and make the dies.

Just so you will know on several loads I have worked up on several barrels it is not uncommon to see shot to shot deviations (5 shot groups) in the 25 fps or less range.
 
Sniper,
I would spend what ever extra there is to get the 338-408 over the 338-378wby imp 40deg.

Ive built many of them in the past and wont do them any more, the brass is not very good for the high pressures your looking at running. The guys that have them wby's ive built are getting 2750 in a 27" barrel, most accurate load. long barreled rifles are are in the 2900fps range. Most end up backing the loads down to save brass life.

If your spending mucho bucks for a custom rig the price of custom dies and brass are a small factor. Barrels are considered a consumable part of the whole rifle, you can load a 338-408imp to 3000fps and that would be a light load, barrel life would be as good or better than a 338-378 using the faster burn powders to achieve anything close to 3000fps.

In the end its all about accuracy first, most guys ive talked to with the hotrod 338-408's
tell me they have settled for 3200-3300fps for the most accurate loads with the 300smk bullets. I seen the article where Joel Russo fired the group from his 338Bigbear, 3.8" at 1650yds, (if i remember right) His load was 3250fps. Ive ran my personal rifle up into the high 3400's, it still shot great but the brass didnt like it. I have backed my loads to 3300ave speed and shoots lights out for a lighter hunting type repeater rifle.

I push the 338snipe tac when ever i can to the guys who want the ultimate in the Big 338's
Kirby's 338am is another choice for the hotrods. There is only two 338's i will build, the Lapua and its wildcats, or the 408 case and its wildcats, i want nothing to do with the belted mag cases, ie Wby.

Dave
 
Sniper,

I too am a drag racer, currently run a 1/4 mile Alcohol car. I'm used to horsepower, lots of it.

And I like horsepower in my rifles also..

Black Diamond is absolutely correct. Build your .338 on the .408 case and improve it. Realistically, you will see 3200-3300 fps with a 300 gr bullet and a 33" barrel. Your accuracy will fall somewhere around the 3200 mark. You can't get there with the .378 or the Lapua case. Barrel life may be a bit shorter than the smaller .338's but that's the trade off for the additional horsepower.
 
What actions are available for the Chey Tac based 338 ? Any of the common big singe shots ?

Apparently lots of shooters like drag racing !! My race car has a 555 in it with lots of nitrous. Low 7 second car, maybe a 6 someday.

Got a tight neck Sniptac 338 reamer ?
 
BAT, Lawton 8500 and 8000, Viersco 1.550 (.750 bolt) or 1.625 or 1.690 dia (.800 bolt)
Repeater or single shot. I have several Stainless Lawton 8000's in stock cut for repeaters.

My reamer is set for a .368 neck (loaded) Basicly no turn with the current batch of brass from Jamison, i still take off any bumps. Reamer will cut for a .372 chamber neck. Freebore is set for the 300SMK bullet. You can order the reamer from Kiff and change the neck dia if desired. contact me if you want more details.

Dave
 
I can't say anything about the big 338s other than one of these days I'll have one.

What I can comment on is barrel life. I have a 270 Allen Magnum in the stable and load it hot. 169 class bullet @ 3300, 195 class bullet @ 3100, 150 class @ 3500 and 140s @ 36xx. If that isn't much more of a barrel burner than any 338 cartridge I don't know what is.

If the 338 based on the improved 408 is used as intended (work up load, get zeroed, validate drop chart, then use for shooting big game animals, barrel life is not an issue especially if your over 50;)

If you take the sucker p-dogin' ....... that's another story.;)
 
BAT, Lawton 8500 and 8000, Viersco 1.550 (.750 bolt) or 1.625 or 1.690 dia (.800 bolt)
Repeater or single shot. I have several Stainless Lawton 8000's in stock cut for repeaters.

My reamer is set for a .368 neck (loaded) Basicly no turn with the current batch of brass from Jamison, i still take off any bumps. Reamer will cut for a .372 chamber neck. Freebore is set for the 300SMK bullet. You can order the reamer from Kiff and change the neck dia if desired. contact me if you want more details.

Dave

There you have it....

Give Black Diamond a call, you won't be disappointed.
 
I have to turn 6 thousandths off the necks of my 30-338lap. in order to get them to chamber. I'll never get another tight neck again. All the neck turning sucks. I agree w/ Blackdiamond, get the neck the right size to just have to knock the bumps off.

jmo, Steve
 
I wouldn't be that concerned about barrel life with a 338 off the chey-tac case if you take care of it. If you are going to hunt with it though it is way to heavy a rifle. If you want a hunting weight rifle you named it. I have worked with the 338-378 wby for 30 years and everything else that has come down the pipe that can be built on a hunting weight rifle that will scope out with a bipod in the 10 1/2 pound range. Still nothing beats the 338-378 wby for performance. I currently own at least 7 of them and they will all get over 3000 fps with the 300 matchking. That can not be achieved with the Lapua case or the ultramag case without blowing it up with incredible pressures. Right now I have some 250 grain Hornady match bullets loaded for upcoming hunts at 3368 fps with a .675 BC. They are shooting extremely well at long range. All of the 7+ are straight wildcat 338's made by necking down the 378 wby. Nothing fancy to it.
 
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