338-06 or 338-06 Ackley Imp.?????

[Wyo. Coyote Hunter]

  From time to time, I have read about these two calibers..What aside from speed would be the advantage of the Imp. caliber..Also, why would the lovers of this caliber choose it over the factory .338 Win.?  In my country, very flat shooting rifles are the norm, and I have a .340, but this round has always had an attraction for me..There must be advantages aside from less recoil..what do you find special about this little caliber??

[jmayton]

I've never shot either, but I'm having a 338-06 being built right now by Dan Pedersen of Classic Barrel Works.  It's just a rebore of a old P-17 Enfield with a bad 30-06 barrel.  I didn't even consider the AI in this build.  There shouldn't be a lot of shoulder there anyway, so AIing it wouldn't seem to have the advantage that it does in other calibers. 

For me, the 338-06 fills a gap in my arsenal right now.  It's not too extremely overpowered for pigs and whitetail and can be extremely effective on Elk.  I doubt I'll ever hunt anything where I'll end up saying, "wish I'd had more gun than the 338."  I think I'll try the Hornady 225gr SST's in it and see how they do.  If I can get decent velocity, they are reasonably flat (.515 bc) and carry nearly 2000ft/lbs all the way out to 400yds.  They stay supersonic to just over 1000yds and will carry 1000ft/lbs to 800yds.  And they should be ballistically similar to a 165gr 308.  That's pretty impressive out of a non-magnum.  So I'm looking forward to mine.  Once I get it back and back together, I'll let you know how it does. 

[Drilling Man]

  In my experience, you just don't gain much by AI'ing the .338-06, and if i was building another, i'd stay with the .338-06 as is.

  I'm really not sure why you would build one, when you can use starting loads for your 340 and still out perform the .338-06.

  DM

[mauser98us]

I disagree. I get about 250 more feet per second out of my 35 Whelan AI over the standard chambering,with suposedley less bolt backthrust due to the 40 degree angle of the shoulder. I would do the 338-06 in the Improved version Doing improved on the standard 06 does not help much,but on the bigger bores it does. Just like the 22-250 and 250 Savage,improving gains a lot of velocity potential. What it boils down to is just personal preference I suppose.

[roper]

From time to time, I have read about these two calibers..What aside from speed would be the advantage of the Imp. caliber..Also, why would the lovers of this caliber choose it over the factory .338 Win.?  In my country, very flat shooting rifles are the norm, and I have a .340, but this round has always had an attraction for me..There must be advantages aside from less recoil..what do you find special about this little caliber??

The only gain would be to build a 338-06 then have barrel set back and rechamber to a 338-06AI and that be what I call real world gain in velocity.

It's been my experience as you move up in caliber the gain from doing the Ackely is less and once you get pass 30cal it gets even less.  You can change afew things like barrel twist add length to the barrel custom throating maybe change from standard primer to mag to gain velocity.  If you build a 338-06 with a good barrel add acouple inches to the barrel custom throat etc you might see more velocity over published data without going over max loads vs doing the Ackley.

One of the few Ackley I got without shooting the parent caliber was a 338-280AI and I fired maybe 50/60rd I now own a 338mag and I also did a 30-280AI beside a 280AI.   Nosler has loading data for the 35 whelen with  max load for the 225gr bullet @ 2805fps do you really thing you could add 250fps when the start load velocity is 2668fps thats a spread of 137fps.    My 35 WhelenAI  has  24" long Kreiger barrel and my gunsmith is seeing how long a wait on a Rock 35 cal barrel finish 25.5"/26" or Lilja barrel for a standard 35 Whelen.

I like that Ackley calibers but I think with all the good barrels being made today in some caliber may be better to build on the standard case.

[crash87]

From time to time, I have read about these two calibers..What aside from speed would be the advantage of the Imp. caliber..Also, why would the lovers of this caliber choose it over the factory .338 Win.?  In my country, very flat shooting rifles are the norm, and I have a .340, but this round has always had an attraction for me..There must be advantages aside from less recoil..what do you find special about this little caliber??

The advantages have always been the same, aside from a velocity increase, which you will get over the std. cartridge. Case stretching is held to a minimum, make that almost nill. But then again will one shoot it enough to really see that advantage. (not many 338/06 Imp.'s in the prairie dog fields expending thousands of rounds in a weekend). An advantage over the Mag, would be another round or 2 in the mag.
 As was posted, to find out your advantage, velocity, is to work up a load in the standard then rechambering to the Imp. If you like the standard over the Imp., well, now, there is no going back. I think, Comparing the the 338/06 imp to the mag. is more in line with the cartridge. Depending on the throating of the wildcat, and for which bullet, which I have found out on a few cartridges makes a huge difference, you are stepping on the heals of the 338 mag. Close enough that it really doesn't matter, unless of course you like to hunt with paper ballistics rattling around in your head. Oh, one more advantage you don't really hear to often is the Improves, look like there goin' 3000fps just sitting there in the loading block. 
  My own 338/06 "is" going to replace my perfectly good 338 mag. Sell it? I think not, Maybe a 416 Taylor 
  Now to nit pick, you wanted to know the differences between the "Calibers"? The correct answer is "nothing" as they are all the same caliber. 338/06, 338/06 Imp., 338 Win. Mag., 340 Weatherby, yep all 33 caliber
crash87

[parkergunshop]

I have built .338 Winchester Mags, and 338/06's and 35 Whelens.

The biggest advantages for the .338 Winchester mag is higher velocity and the availibility of factory brass and ammunition. 

The big advantage for the other two is that, You can use a standard, 8 m/m Mauser Action or a standard 30-06 action for the 338/06 or 35 Whelens and reduce the cost over converting a standard  action to a Mag bolt face and sometimes opening up the rails on the action for proper feeding for a .338 Winchester Mag.   If you start out with a 1914 Enfield Action for the .338 you don't have to make magnum modifications to it, just install a .30-06 magazine box.  But you have the extra expense of removing the ears from the back bridge on the receiver unless you can do it yourself.   A file and a bench grinder is all that's needed if you make a template to go by.   

One thing of note the 1914 and 1917 Enfield actions are heavier and more rigid than the other military actions which helps with the accuracy issue, and reduces the felt recoil due to the extra weight.  Weight helps, I woud not build one weighing less than 8 pounds without scope and mount.   I for one don't like muzzle breaks to reduce recoil, the extra noise and  resulting ear damage defeats the purpose, I'll take recoil over the noise.

Unless you are a handloader or are willing to handload go with the .338 Winchester Mag as not eveyone has the patience to form 338/06 or 35 Whelen Brass and work up proper loads.

Either of these three will shoot 1/2 inch three shot groups or less given a good barrel, load development and stock bedding job, there is little difference in accuracy and I find the big bores to be easier to work up good accurate loads for.   Recoil can be an issue with these medium bores.  Note I'm not bothered much by recoil some folks can't handle the kick of a 30-06.    The only two guns that hurt me on the bench have been the .458 Winchester Mag factory loads and a Ruger No1 in 45/70 pushing a 350 grain bullets to 2250 FPS.

[possume]

sorry posted on accident

 

[yooper77]

From time to time, I have read about these two calibers..What aside from speed would be the advantage of the Imp. caliber..Also, why would the lovers of this caliber choose it over the factory .338 Win.?  In my country, very flat shooting rifles are the norm, and I have a .340, but this round has always had an attraction for me..There must be advantages aside from less recoil..what do you find special about this little caliber??

I have 2 rifles in 338-06 A-Square. Weatherby Mark V Ultra Lightweight and a T/C Encore 24” stainless steel barrel originally as a 30-06 Springfield factory barrel, was re-chambered/re-bored to 338-06 A-Square by Classic Barrel Works in Prescott AZ. http://www.cutrifle.com/reboring.html

This cartridge just makes sence for me. I use only 30-06 Springfield brass which is so easy to re-size and load.  I have IMR-4320, IMR-4064 and IMR-4350 with bullets from 180 grain to 250 grains. I feel I don’t need a belted magnum, since the 338-06 A-Square does it all just a tad slower, which obviously make no difference under ethical hunting ranges.

I do own 2 Ackley Improved cartridges and they are 30-06 Springfield AI and 7mm Mauser AI. I don’t attempt to push these any faster than factory standards, but the true benefit is almost zero case stretch.

yooper77

[jmayton]

yooper77, can I ask how well that rebored rifle shoots?  Dan is currently doing one for me on a 1917 Enfield.

[yooper77]

jmayton,

I haven't shot it yet I just bought it this winter.

I bought it used and the fella that sold it was getting MOA.

yooper77

[bigswede]

The 338-06 or 338-06AI are not on the same level as the 338 caliber magnums.  They are just good cartridges that propel medium sized projectiles at modest velocities, and kill game with much authority out to ranges they were intended for.  I built mine a little over a year ago, it is the Ackley version.  I have always thought the 338-06 was a good cartridge just from what I had read about it, good bullet selection-needs a standard length action-less recoil than a magnum- effecient game stopper.  The reason I went with the Ackley are twofold, first off minimal case stretch and secondly is the main reason-- no else I know has one and I wanted to be different. 
    I have found my rifle to be very accurate and easy to load for.  I started with once fired R-P 30-06 brass, annealed it, sized the cases, and loaded up some medium power loads to fireform with.  I spent all last summer practicing with my fireforming loads.  I eventually ended up with a 200 gr Hornady as my hunting load.  It performed exceptionally well on game, I took an elk, whitetail deer, and my mom even shot her mulie with it.  All three animals dropped in there tracks and there was very minimal meat damage with the 200 gr bullet.  I had actually expected more blood shot with a small for caliber bullet like that but got very little if any at all.
     I would highly recommend this cartridge for a handloader.  If a person had to shoot factory ammo, I think there are better choices out there.
   YOOPER77, Have you shot any 275gr slugs out of your rifles?

[yooper77]

bigswede,

I have only shot my Weatherby Mark V Ultra Lightweight rifle and harvested one deer. I used Nosler/Winchester Combined Technology 200 grain Ballistic Tip using IMR-4320. At approximately 125 yards I took a large white-tailed doe and she rolled over at the behind the front shoulder double lung shot.

I bought my Weatherby used and it came with RCBS dies, some Weatherby brass and some bullets (included two 275 grain and two 300 grain), I loaded all four but they had to be hand fed, since they wouldn’t feed out of the magazine. The heaviest bullet I would load anyway is 250 grains. I have a huge selection of bullets to choose from now 180, 200, 210, 215, 225 and 250 grains. I am going to try IMR-4320, IMR-4064 and IMR-4350 and yes once fired 30-06 Springfield brass. If I were to pay for a built rifle I would choose the Ackley Improved as well, but I bought mine used already made and saved a lot too.

yooper77

[Drilling Man]

  I've shot a LOT of big game with 338-06's since Parker Ackley built my first one for me in the 70's...  I settled on 275 Speers for my big bear load, and found it very effective when crawleing around the alders following up wounded big bears. 

  It's a great cartridge, it's just these days i don't need a cartridge with that much power to kill a deer or other softer big game...

  DM

[bigswede]

  I've shot a LOT of big game with 338-06's since Parker Ackley built my first one for me in the 70's...  I settled on 275 Speers for my big bear load, and found it very effective when crawleing around the alders following up wounded big bears. 

  It's a great cartridge, it's just these days i don't need a cartridge with that much power to kill a deer or other softer big game...

  DM

So with your way of thinking my 350 rem mag,  358 Norma, and 338-06AI are overkill for the deer and elk I kill with them

[Drilling Man]

  Maybe NOT for you, but they ARE for me...   

  DM