30-06 vs. 30-378

[hemiford]

In this post I am touching on several BIG topics, but I'll try to sum them
up with one question.

22" barrel length is common to many 30-06 rifles. Since a 30-378 Wby
has very close to twice the powder capacity, why doesn't a 30-378 rifle
have a 44" barrel ?? This would give each rifle the same expansion ratio.

???

On a side note, this should also give the 30-378 bullet about 1.414 times
the muzzle velocity of the 30-06 (same bullet weight).
I.E., 3800 fps vs. 2700 fps.

I have done a lot searching to find graphs of the internal pressure traces
of large capacity cartridges, to compare with a typical 30-06 pressure trace,
and have not found good comparative results.

I have done this with gasoline engines and compression ratio, which is a
VERY similar situation.

Aside from the inconvenience of carrying around a very long barrel, I see
this as a simple engineering exercise in scaling.

 

[MudRunner2005]

Wow...That scared me when I saw the title. I thought you were wanting to compare the 2 ballistically.

I was gonna say, that's about like comparing a slingshot to a tomahawk missle. LOL

The .300 Sherman is a better ballistic comparison than the standard .30-06. But they're still far apart.

Also, the .30-06's really will shine with a 26" barrel.

The reason they don't need a 22" vs 44" barrel is because even though it has twice the powder, the powder won't burn as fast creating more pressure to push the bullet faster, therefore it doesn't need a 44" barrel. The .30-06 will use a faster burnng powder only requiring a 22-24" barrel to reach good velocities.

 

[LONGSHOOTER]

You talk as if these processes are to occur in a linear fashion.

My suggestion? Keep studying.

 

[Michael Courtney]

If you're going to get the same efficiency with the same bullet weight, you'd need a much longer barrel.

Overbore cartridges are much less efficient, but it helps that most overbore cartridges are used with longer, heavier, high BC bullets. A 208-230 grain bullet can use the extra powder in a shorter barrel length than a 150-165 grain bullet.

But adding more powder capacity and much greater powder charges to a cartridge is almost always a situation of demishing returns.

 

[Sral1987]

Wow...That scared me when I saw the title. I thought you were wanting to compare the 2 ballistically.

I was gonna say, that's about like comparing a slingshot to a tomahawk missle. LOL

The .300 Sherman is a better ballistic comparison than the standard .30-06. But they're still far apart.

Also, the .30-06's really will shine with a 26" barrel.

The reason they don't need a 22" vs 44" barrel is because even though it has twice the powder, the powder won't burn as fast creating more pressure to push the bullet faster, therefore it doesn't need a 44" barrel. The .30-06 will use a faster burnng powder only requiring a 22-24" barrel to reach good velocities.

extreme exaggeration, the .30-378Wby does hit the same 200 yards farther, thats it basically