Home Forums Hunting & Shooting Custom Rifles & Wildcats .338-06 AI vs. .338 WSM?

Here's a thought experiment for y'all. Which would you go with, .338-06 AI, or .338 WSM, and why?

For me, either makes more sense than a .338 WM. Lighter, shorter rifle, and plenty of power for anything in North America including at least defensive duty against the biggest bears. My feeling is that the 225 gr. mono bullets will do anything the older 250 grainers (say, Partitions;) could do.

I'm sure some would say just go with the straight .338-06. I feel it's a little anemic compared to the "ideal" case capacity, and I'm attracted to the better brass life with either of the other alternatives. Whichever one I end up choosing, I'll use a M70 Classic action as the starting point.

As I see the tradeoffs, it seems with the .338 WSM I'd have a short action and a bit more powder capacity, at the expense of one less round in the magazine. Both of them have been accused of feeding issues, and I've heard claims that both can be made to feed well.

I suppose the other thing is I haven't looked into the .338 WSM dies, but I have seen the 40 deg. Ackley .338-06 dies available.

So, thoughts?

I did the 338-06Ai over the 338WSM for a few reasons. I got the dies dirt cheap from a guy that his smith [bleep] up his chamber, made it a Gibbs and I had an 06 action sitting here trued and ready to barrel. I got a 338-06Ai reamer, print and guage for sale if you are interested.

My Model 70 SS Classic 338 Win Mag weighs 8.37 with scope. And I'm not sure I would want it any lighter than that. Both of the cartridges you mention are wildcats. If that's not an issure for you, then have at her. Personally I don't see the advantage though. With both of them, you are trying to approach a known commodity, in terms of power, as the 338 WM. If so, why not just go with it? Lot's better choice of rifles, and easy ammo access. The 225 grain bullet of any make is going to really rock in terms of recoil, so personally I want some gun weight. In terms of resale, the 338 WM will always sell better than the wildcats too.

My thought's? Your wasting your time and money when you can go out and buy a rifle that will do everything you want to accomplish. I've used my 338 on Whitetails to Grizzlies, and it works just fine. Can't see where either of the wildcats you mention would be better in any practical way. As to the advantages of a short action, I think they exist more in the mind than real world performance. If I was bound and determined to own a short 338 mag, I'd go with the Ruger. As to Wildcats, they just don't appeal to me that much. Seems to me your just reinventing the wheel.

Yep

I do need to find a reamer either way, my smith only has the straight .338-06. Is yours the "official" 40 deg. shoulder AI, same as Redding dies? I'll take first dibs, depending on price. Send a PM please...

The same argument can be made in almost every caliber.

Why do a 223 AI when you can do a 22-250, or why do a .......

They don't always make sense.

Whatever floats YOUR boat.

Nope. I'd be quite satisfied with a 225 gr. bullet at 2650, which is a bit above .338-06 A-Square levels, but well below .338 WM.


How much it 'rocks' depends on MV, stock design, muzzle brake or lack of same, etc. Do you think an 8 lb. .338-06 AI will kick more than my 7 lb. .300 WSM Montana? ;-)

Further, I won't be shooting 225 grain bullets all the time, or even most of the time. 180-215 grainers will do fine here in the South. But, it'll be nice knowing that if I do head to AK, which is a goal of mine, I'll be set.

(If I actually go to specifically hunt brown bears, I'll likely get a .375 of some flavor. Just FYI.)


The .338 RCM did occur to me as well, and I might take another look at that. It would solve the brass headstamp issue. The factory ammo for that is oriented towards 20" barrels, and I'm looking at 23"-25", but given that I handload anyhow I guess it's not an issue. .30-06 brass would be a lot cheaper component than either of the short mag brass, of course.

I have no desire to shoot at big game over 400 yards anyhow, so probably the lower recoil, muzzle blast and cost of reloading push things in favor of the .338-06 AI.

Resale value is of no concern, as I have no intention of selling once I get this built.

Logistics favor a 223AI and I can still fire factory ammo in it. AI's ain't true wildcats.

Steely, wasn't dissing one of your favs, just using it as an example to try and make a point.( ya, I run one too)

Which is, in your caliber of choice, pick a weight you wanna run, and pick a case that runs it at the velocity (and recoil) your looking for. Don't choose a 300 Savage if your after Weatherby velocities.

On another note, I sold my 338WM and built a 338-06 AI instead. Iffen that won't do it, I can fall back on my 375.

Hell, don't bother me none.

I did some nosing around the Hogdon site for load data.

The .338 RCM looks to be quite anemic (top vel load):
225 GR. - HDY IB - BL-C(2) - 58.0gr - 2689 FPS - 61,500 PSI

Compared to the unimproved .338-06 (BLC-2 wasn't the best powder, but it was very close):
225 GR. SPR SPBT - BL-C(2) - 55.0gr - 2671 FPS - 62,900 PSI

I'm assuming both were tested in a 24" barrel...I have no idea how Hornady can claim 2850 FPS for its factory 225 gr. .338 RCM ammo...

At any rate, if I go short/fat it'll definitely be the .338 WSM, with around 65 gr. of powder capacity with the 225. I'm leaning more and more (back) towards the .338-06 AI though.

Whatever works for ya! I can load down, or go up. If the 338-06 AI trips your trigger, then go for it. Me, I'm more interested in hunting than worrying about a few feet per second one way or the other.

I could definately see the advantage to an Ackley over another wildcat though, if the caliber you were Ackleyizing was a common production cartridge. The 338-06 ain't though. The 338 WSM makes zero sense to me. I'd choose the 325 WSM over the 338 if that's what you're after.

However, there's a saying I've heard before, goes something like this. "To each his own..."

I ran numbers on the WM vs. '06 quite a while ago and was rather astonished at the results.

I just built an '06 and had assumed I'd someday want a WM, but found that on an apples-to-apples comparison of the fastest loads for each w/ the 200 gr Interlock the difference was something like 150 fps (show me an elk that'd tell the difference between the two!) or something like 5% more velocity for 18% more powder. Huh?

If you're dedicated to a wildcat I'd go w/ the AI, personally. If you're looking for greater efficiency I'd go w/ the AI or straight-up A-Square, personally, WM under consideration or not.

The RCM is just an '06 in a short action that'll be a distant memory within a decade, IMO.

The case capacity is the same, so it's no surprise that the velocities are too (except in factory pixie dust loads).


But I've seen your quote before . . . oops, maybe it was




_

I have hunting tools that'll do the job now, a custom rifle is more a labor of love, no?

As for up or down, I honestly see no meaningful difference between a 225 gr. bullet at 2700 (which I should easily hit with the AI) and 2750, which is Hornady's factory .338 WM load.

Now, the one unfair thing there is both of those velocities are from a 24" barrel, where many .338 WMs have a 26" barrel. It used to be that magnums that usually sported a 26" barrel got to report stats from those barrels, but times have changed I guess. How long is the barrel on your lightweight .338 WM? Also, what contour? Heck, post some pictures! lol


The selection of 8 mm. bullets is terrible compared with .338. The .338 WSM may make zero sense to you, but to me it makes a lot more sense than the .338 Federal, or the .338 RCM. I wish Winchester would add it to the factory WSM stable. However, with modern bullets I think it's actually overkill for any NA game, except possibly the biggest bears. I'd still feel secure toting a .338-06 (AI or not) in big bear country, personally.

I'll fireform a couple hundred brass or so, and that should last me for, um, long enough. ;-) I might even just get some Weatherby .338-06 brass, so I have a headstamp and get some range time while fireforming. Otherwise, I'll use the "Cream of Wheat" method with .30-06 brass.


True enough. Here's to hoping you rack up many future trophies with your .338 WM. :-)

My 338 has the factory 26" barrel. I don't use 225 bullets myself. I use 210 Nosler's for everything. Whitetails, Blacktails, Elk and Grizzlies. The 225 Nosler's I've handloaded have run about 2820-30fps. I could go faster, but I'd just be adding recoil.

Here's a pic of it and a small Whitetail I shot a few years ago.





It's nothing fancy, but it's very accurate. Chambers and ejects shells perfectly. I added a recoil pad and had some trigger work done. Most of the animals I've shot with it have dropped at the shot with the 210 Nosler's. The Grizzly I shot in September went about 50 yards and needed only one 210 Nosler.

Had my gunsmith last year build me a 338-06AI with a new barrel placed on a Sako m75 Greywolf. Shoots 225gr Accubonds @ 0.5" groups so far and thats just with new brass to be fireformed and break-in of barrel. Plan on trying 225gr TTSX's too. Gunsmith ordered me Redding dies.

Love the rifle. I posted last fall(November) a topic about my new rifle.

Had my gunsmith last year build me a 338-06AI with a new barrel placed on a Sako m75 Greywolf. I went with the Ackley version just to be different and by the reccomendation by my gunsmith. Shoots 225gr Accubonds @ 0.5" groups so far and thats just with new brass to be fireformed and break-in of barrel. Plan on trying 225gr TTSX's too. Gunsmith ordered me Redding dies.

Love the rifle. I posted last fall(November) a topic about my new rifle.

Yeah, you're right; time will tell.

Of course it does bear mentioning that the 284 lives on mostly as fodder for reloading its more popular necked-down wildcats like the 6.5-, or 25-, or 6mm-284s.

But you're right, time may tell a completely different story.

338 win mag is the origional short mag. no need ofr improvement