The difference detween 123gn & 140gn in Quickload!!

[walkabout]

I have just run some numbers through Quickload.

 

6.5 x 47 Lapua

Same powder, barrel length, temp.

Pressures virtually the same.

Case fill 102% for both.

Not sure the figures being put out are right?

I know Quickload is a guide but is the Berger 140gn Hybrid that good?

Look at the 600 yard wind deflection figures between the two.

 

123gn -23.6"

140gn -8.4"

 

I must be putting in wrong figures somewhere?

Or is the Berger that good?

 

Mark

 

 

 

 

 

[Laurie]

No, you have something far awry here.

 

123gn Scenar, G7 BC 0.265 @2,804 fps = 26.76 inches drift in a 10 mph wind at 600.

 

140gn Berger Hybrid, G7 BC 0.317 @ 2,653 fps = 23.45 inches drift in a 10 mph wind at 600.

 

Both BCs from Bryan Litz and using the Berger Bullets / Applied Ballistics software.

[blackburnbuccaneer]

I think you will find you are using the G7 BC for the 123gr, but are using the G1 for the 140gr Hybrid, but you still have quicktarget set for G7 BC so it is interpreting it as a G7 BC of 0.618.

 

You will need to click the box that says G7 to change it to accept the G1 BC or better input the G7 BC, best to compare like to like.

[walkabout]

I thought I was doing something wrong!

Now I look at it I can see the BC fault.

Thanks guys

 

Mark

[gbal]

Mark,it's easily done especially with defaulting settings.

You had the good sense to use the eyeball test-my statistics guru always said when you do stats/calculations/formulae and the like ,finish with the 'eyeball test'-just have a look and see if the results seem plausible...as you immediately suspected,your first set were not.

Of course,when the error reduces,it may not be possible to detect/raise suspicions-but it avoids some real boo boos if you do check,as you did.

 

gbal