I've heard these two rounds have very similar ballistics but I'd like to learn about the differences between the two.

What are the pros and cons of each and can one be considered better then the other?

The .338 will always shoot bullets with a better ballistic co-efficient and a higher sectional density than comparable weights in any .35 caliber. The .35 hass the advantage of being able to use .357 acliber pistol bullets for plainking/small gameuse if you are a handloader and are so inclined. Beyond that, I don't know that there is much real world difference.

I just got a .338/06 barrel last month and I'm getting ready to put together a Mauser in .338/06.

Where and what are you gonna hunt?

I have had my .338-06 since 1998. I had a Kreiger barrel put on a 700 action. I chose the caliber so I could have something a little different. I was attracted by the wide variety of available .338 bullets, and I wanted a larger bore rifle without the recoil of a monster magnum. Many of these attributes can also be applied to the .35 Whelen Improved. These two calibers are nearly ballistic twins, but there are some slight differences between these calibers, some have already been mentioned.

.338-06 advantages:
better ballistic co-efficient and a higher sectional density of same weight bullets
more bullet selections
no need to fire form cases


.35 Whelen Improved advantages:
slightly higher velocities with heavy bullets
ability to use pistol bullets for low-recoil target shooting
readily available factory ammo in .35 Whelen

I can only see one cure for this problem. Build one of each. Thats always been my answer. Thats why I am poor but have lots of guns.

I too am looking to build a 338/06. The questions I have are; information on ballistics for longer range shooting and the diff. between Ackley & A-Square?
According to FederalAmmo Ballistics Catalogusing a high energy 30/06 180G @ 140yrds can surpass a 300mag/180g & close to a 338mag/210g inenergy at 300y. Can the same be said for the 338/06?
Anyone have any charts or where to go to for the info? Sure is a lot cheaper to shoot and reload than a 300 or 338mag.

In the early 80's i built a .338-06 useing a Douglas premium bbl on a 700 Rem. action, and harvested 13 big game animials the first 3 years ihunted withit.Iharvested moose, caribou, bown bear, blk tailed deer and many others. Useing good bullets it worked very well and i was quite pleased with it.

I chose the.338over a 35 cal. because "those days" getting good quality 35 cal. bullets wasn't easy, and the bullet i'm talking aboutare Nosler partitions! Also Speer made the "excelent" 275 grain bullet that really knocks big bears flat at 338-06 velocities back then!

Today, choose what ever one you like, and for deer sized game, both have plenty of bullet offerings that will easilyknock that size animial flat! I have to admit the fact that you can use .357 pistol bullets in the 35 would be a big advantage for small game and practice.


Drilling Man

Lots of good technical talk here and that's important to some.

Lets talk about the ackley Improved.

for almost all the cases we will discover (if we have the correct pressure reading equipment) that the ackley Improved cartridges actually offer very little over the parent case in terms of velocity. In some cases the gains are less than 50'/sec and in some cases there is no gain at all.

Possible exceptions are the .250 savage where greater gains to case volume are made than a .30-06 for example. There might be others but far and away the benefits of the AI cartridges are way over stated, exagerated and in general pure BS.

At best you might get 50'/sec gain with a .35 whelen improved over the .35 whelen parent cartridge. Bear in mind that a major league baseball pitcher can throw a baseball at 150'/sec........if that puts it in perspective.

Now to the question of the .338-06 verses the .35 whelen (improved or not) IMO it's six of one and a half dozen of another. There is nothing you can do with one that you can't do with the other. There is no game animal on the planet can tell the difference. Personally I would prefer the .338-06 but out of pure prejudicial reasons and not out of any practical differences. Add to this the 9.3 X 62 mauser and we have a fine trio of near twins.....or triplets as the case may be.

All of these have great range for their bullet weight and immense knockdown power for big game and (if legal) for dangerous game as well.

Just one more fly in the ointment here.....as good as these rounds are there's very little gain in any of them over the good old .30-06 for big game. If you need more than a .30-06 you really ought to be looking at a .375 H&H.

Its true, Until you do the conversion, there is no way to know what kind of gain you will get. I have seen No gain in a few Improved 06's to as much as 200 fps. Same for the 25-06 which is already overbore.

I would never be willing to bet money on the outcome of these conversions. Like you said, the 250 Savage and the 22-250 seem to be exceptions and case life in the 22-250 is probably well worth the conversion as it usually stops case length growth. IME

Let me throw a stick in the works here. I looked at the Whelen and the 338-06 and ended purchasing a .350 rem mag instead. The .350 is virtually equal to the Whelen and the 338-06 is extremely close also but the model 7 remington weighing 5 7/8 lbs is what sold me. A week walking around the bush with the little 7 is far more enjoyable than lugging a full sized bolt rifle. And that .350 pretty well crushes game, what more can one ask for