at what point

[rickyp]

when you are comparing case capacity in the same caliber IE 308, 30-06 300 win mag In a handgun. at what point are you no longer get any benefit   and start to just waste powder?

[Jeff Vicars]

A bigger case with the correct powder at the same pressure will always yield higher velocity regardless of barrel length.

[MS Hitman]

rickyp,

This is a good question and I would only ask that you clarify the context of waste as you are using it.

[rickyp]

that big ball of fire that comes out of the front of the barrel when it is shot that is all unburned powder that once hits the air ignites.

hypothetically a 308 uses 41.2 gr of IMR 3031 with a 150 gr bullet  and the 30-06 used 49.0 of the same powder with the 150 gr bullet.
the 308 is 2700 fps out of a 15 inch tube and the 30-06 will give you 2750 fps out of the 14 inch tube.

Is the extra 7.8 grs of powder from the 30-06 Worth the 50 fps?

now if you already have the setup for the 30-06 that is a diffrent story.

[MS Hitman]

I personally don't believe either the extra 8 grains of powder or the 50 fps make much difference.  As in the case of most caliber choices, it is usually driven by need or preference.  I'd go the route of the .308 over the .30-06 just because it's my preference.  Either round is quite common, so finding factory ammo in a pinch wouldn't be a problem.

I would consider the .300 Win Mag if I needed to launch larger bullets for larger game or wanted to shoot longer distances.  Then the extra powder consumption would be warranted in my mind and not considered a waste.

I'm doing this very thing, but with a rifle.  Opted for a .300WM because I wanted to shoot at ranges exceeding 1000 yards.  This cartridge is my preference for this job and I do not consider the extra powder used in the larger case a waste.

Hope this helps.

[helobill]

rickyp,
Kinda goes back to the "does barrel length effect velocity". Lots of articles written about it, some actual experiments done with cutting a barrel down an inch at a time to see what the effect really was. Same thing here,  basic law of thermodynamics says pv=nrt (pressurexvolume=moles of gasxconstantxtemperature). So the question becomes, can you burn the powder to create the pressure as the volume changes as the bullet travels down the barrel and the temperature rises before the bullet leaves the muzzle. Since all those variables exist (including the fact that the equation is for an ideal gas and has 'issues' during change of state, ie solid gunpowder to a gas) the debate will continue for a long time. Hard to prove. If I had more money and time than I knew what to do with, I'd go buy three like barrels and test them side by side with the same lot powder and bullets just to settle the debate in my mind. Course someone would say it was the barrels internal differences that caused the results and wouldn't believe what I observed (moon was wrong, wind was blowing, etc) So we come back to what MS Hitman said, really boils down to personal preference. I too like the .308 over the 30-06 but it's funny how the 30-06 is an accepted Elk round and everyone seems to think the .308 with the same bullet going 100-200fps slower isn't.
Bill

[handcannon]

Hey guys;When you go down in barrel length you loose velocity no matter what most of the time..It is up to the shooter to find out if the round meets his or her requirements.My 300 Ultra Mag in a 15" barrel shoots a 150gr Nosler BT at 3150fps with 104gr of powder.Is this a effiecent cartdrige no but it hit the velocity I wanted to get to.Some might say that I am burning way to much powder and i am but I am happy with the results that I am getting.It is up to the shooter and what he is going to go for to decide if it is way to much powder(recoil)for his or her given use.Just my two cents.  Wade

[rickyp]

handcannon.
Have you tried backing off the powder to see if you can get the same speed with less?

have you actually clocked the bullets or are you going by published data?

[Bullseye]

I guess it is an individual choice, but you will have to hit a point where you are adding a bunch of powder and not gaining much because you do not have enough tube.  Example, 22 Hornet.  It looses very little between the rifle and pistol, why, because a short tube is long enough to burn the powder.  Same with the 30-30, it looses very little for the same reason.  30-60 and other loose more because there is just not enough tube to burn the powder.  Same is true with Muzzleloaders.  Look at a velocity chart of loads going from 100gr of powder to 150grs.  The velocity increase continues to drop off per increment, why, because you are not burning all the powder.

Now your question was where is that point.  Heck I do not know but I feel sure that what I stated above is true in my opinion, but it is up to the individual to draw the line for themself.

[rickyp]

I have a comparison chart ( Harold's comparison) this was sent to me by a another member. It is very interesting and it looks like he put a lot of work into it. he compares the encore in 308, 30-06 and 300 win mag.

he used  180 gr bullets and the 15 inch encore tube

308: 42.1 grs of w748 gave 2320 and 21.6 ft-lbs of recoil
30-06: 50.5  grs of VitN550 gave 2400 fps and 25.6 ft-lbs of recoil
300 win mag: 71.6 grs of IMR 4831 gave 2444 fps and 34.4 ft-lbs of recoil

Do you think getting only 124 FPS is worth the extra 29.5 grs of powder and a significant increase of recoil?

to me with-in normal hunting conditions the 124 fps will not make enough of a diffrance to warrent the increse in recoil. Infact the heavyer recoil could do more harm then the 124 fps will help.

[MS Hitman]

rickyp,

That's one stout .30-30 load ya got listed there.  Typo, I know.  Now what are these same barrels doing with 200, 220 and 240 grain bullets?  I have not done any testing in the Encores, but the premise of the larger straight wall cases has been to be able to drive heavier bullets at the same velocities that the smaller rounds push lighter bullets or drive these lighter bullets faster than could be done before.  I believe that once one gets into the heavier .30 caliber bullets, the velocity gap will widen.  This would make for some interesting testing, but it is the case in rifles.  A .308 can not drive a 240 grain bullet as fast as a .300 Win Mag can.  So as I stated above, if this was what I wanted to do I would not consider the extra powder consumed a waste.

[rickyp]

That's one stout .30-30 load ya got listed there. Typo, I know.

thanks for pointing this out to me. sometimes I do not catch every mistake I make. i went back and fixed it.

I am not sure what the heaver bullets will do. The information was off a chart another member sent to me.  I did not do any of the work on it. You  are right a 308 will not push a 220 well.

If you feel you need or just want to shoot the 220 bullets. then go a head and enjoy the 300 win mag and don't think twice about using the extra powder.

[handcannon]

rickyp;All loads have been worked up to and ran threw a chrony a few times.
 
    Reason I went with the Ultra Mag.Have a Rem 700 PSS in 300 RUM,Did not want a belted case (300 Win Mag),wanted to get 300 Win Mag perfomance in a pistol,long range shooting,had not been done,still has not been done again as far as I know.I like the perfomance of it in the short barrel it did loose more velocity than what I wanted but it hit the makrk I wanted 180gr Nosler BT at 3000fps,even though it blew the primer and I did have to back down to 2900fps and a little above that.The 125gr Nosler BT does 3300fps in my 15" barrel and out of my PSS it does over 3900fps.So I have lost a munch going to a shorter barrel.     Wade