338's: 250 gr vs300 gr bullets

[biggjake]

338\'s: 250 gr vs300 gr bullets

I'm looking for info on the performance between these 2 bullet weights in the larger magnums,such as the Lapua,RUM,and 338-378.Does the incredibly high BC of the 300 really outdistance the 250's at 1000+ yds?Or are the 250's at 150+ fps faster just as good?

 

[ewallace]

Re: 338\'s: 250 gr vs300 gr bullets

The 250g with a BC of .565 at 3250 vs the 300g with a BC of .795 at 3050. The 300g caches up with the 250g at 920 yards. The windage is 300g all the way as is energy.
Crow Mag

 

[Sausage]

Re: 338\'s: 250 gr vs300 gr bullets

Crow Mag:

Which cartridge are you able to achieve those impressive 250/300 grain SMK velocities?

Please specify Barrel length and rate of twist.

I am hoping you are shooting a 338 Lapua.

Thank You.

 

[ewallace]

Re: 338\'s: 250 gr vs300 gr bullets

Sausage
It is a 338 Lupua improved 34in barrel 1 in 10 twist

Crow Mag

 

[Sausage]

Re: 338\'s: 250 gr vs300 gr bullets

Crow Mag and Biggjake:

In your opinion would you guys be hard pressed in obtaining 3000 fps from a 300 SMK chambered in a 338 Lapua Magnum from a Accuracy International 1/10 twist 27 inch barrel?

If so, what might be the maximum velocity from the above mentioned 338 Lapua Configuratuion?

Note: The 250 grain Lapua Scenar yields a .659 BC.

Thank You again.

[ 11-04-2002: Message edited by: Sausage ]

 

[Brent]

Re: 338\'s: 250 gr vs300 gr bullets

Sausage,

My brother has a 32" Pacnor barreled 338/378wby which has I think about 5-10gr more capacity than the Lapua Imp and even a little more yet than the regular Lapua. Steve Shelp knows for sure. It will push a 300gr SMK at 3000 fps at between 64,000 and 67,000 psi over the Oehler 43. Which I might mention at this point, was the same load at 118gr of H870 at 4.100 OAL that produced 59,000 psi with virgin brass. It has been loaded 4 times without being annealed and psi has moved up that much. Same powder lot so it is the brass.

Interestingly enough, the original 65,000 psi load of 120gr was grouping at just over 1 MOA and the 118gr load under .7 MOA.

The velocity has raised with the psi too with the work hardened brass by 50fps but it still groups under .7 MOA every time.

Thought some of you might find that interesting.

I would guess that 2800-2900 would be possible in the standard Lapua chamber and another 100fps availible with the Improved version in a 27" tube.

 

[Sausage]

Re: 338\'s: 250 gr vs300 gr bullets

Guys:

Do any of you know if the Swift Scirroco Bullets are offered in 338 Caliber? If so, in what weights?

Thank You again.

[ 11-07-2002: Message edited by: Sausage ]

 

[Ian M]

Re: 338\'s: 250 gr vs300 gr bullets

I talked to Swift a little over a week ago and the Scirocco is not out in .338 yet. They were working on it but delayed. Said it would be a 210 or 225 grain bullet. At that time they were not sure when it is going to be ready.