[mcnurlenj]

I cut and pasted this data from an old thread on here.



168 Sierra Match King
41.5 gr H4895
IMI case
CCI Br2 primer
2.800" OAL
about 2550fps from 22" barrel

I'm not sure what volume an IMI case has so used 56.0 grains of water. That created a match between the QuickLOAD's estimated muzzle velocity and the one you listed.

QuikLOAD's estimates
2551 fps
47,445 PSI (chamber pressure)
13,639 PSI (port pressure after subtracting 1,000 PSI)



When I input the same information I get different results.
I get.
2568 fps
49232 psi chamber pressure
13452 port pressure. Using 14in bbl length and muzzle pressure at that length
13439 port pressure using chamber pressure and bullet travel graph

Any idea what I'm doing wrong. I
The data is from a respected Quickload user who is not here anymore so I figure I must be doing something wrong.

 

[mcnurlenj]

Anyone??

 

[4th award expert]

I don't have an answer to your question but I can give you the results of my testing.
168gr SMK
LC85 match brass, once fired.
41.5 gr IMR 4895

Low 2452 fps
Hi 2509 fps
Avg. 2482 fps
ES 56.44
SD 17.69
Fired from my Polytech standard with 22" barrel
Bob

 

[mcnurlenj]

Thats about what i get too. Thats why I'm so confused.

 

[mcnurlenj]

My hunting load is
Lc brass
Sierra 165 hpbt
41.5 IMR 4895
Avg 2496
High 2517
Low 2482
Sd. 11
Spread 35.
6 shots registered on chronograph.
3 shots at 3 deer. 2 Drt, 1 ran 30ish yds

This load close in QL. Estimated 2509.

This is why I am confused. I cant get the results others have on QL. I fear I am doing something wrong.
My QL predictions are way off on a 7.62x54R too.
I get 2524fps avg. QL predicts 2617.