I just finished up a seating ladder test for the 200gr AB in the .338Wm and while I was at it I ran them over the chronograph. Nosler shows 76.0grs of RL19 with a 200gr AB at 3040fps. I loaded 76.5grs under a 200gr AB and only got a 2822fps avg for 9 shots out of my 24" barrel. It shot under 1/2" 3 shot group at 100yds. Very disappointed in the velocity. Is this normal for RL19?

QL calculates basically the same as the Nosler manual. However it will list your velocity as a 10% lower burn rate. Also a simple increase in case capacity of 2grs would drop the forecasted velocity by almost 100fps.

For your info

 Cartridge          : .338 Win Mag.
Bullet             : .338, 200, Nosler Accubond 56382
Useable Case Capaci: 74.990 grain H2O = 4.869 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Alliant Reloder-19

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-20.0   88    60.80   2372    2498   31098   8056     85.4    1.489
-18.0   90    62.32   2433    2630   33257   8339     86.9    1.448
-16.0   92    63.84   2495    2765   35572   8617     88.2    1.408
-14.0   95    65.36   2558    2905   38058   8887     89.6    1.367
-12.0   97    66.88   2620    3049   40730   9149     90.8    1.324
-10.0   99    68.40   2683    3198   43600   9402     92.0    1.282
-08.0  101    69.92   2747    3350   46692   9644     93.2    1.242
-06.0  103    71.44   2810    3507   50021   9875     94.2    1.204
-04.0  106    72.96   2874    3668   53616  10092     95.2    1.166  ! Near Maximum !
-02.0  108    74.48   2938    3832   57499  10296     96.1    1.130  ! Near Maximum !
+00.0  110    76.00   3002    4001   61703  10484     96.9    1.095  !DANGEROUS LOAD-DO NOT USE!
+02.0  112    77.52   3066    4174   66258  10656     97.6    1.062  !DANGEROUS LOAD-DO NOT USE!
+04.0  114    79.04   3130    4350   71205  10811     98.2    1.029  !DANGEROUS LOAD-DO NOT USE!
+06.0  117    80.56   3194    4531   76585  10947     98.8    0.998  !DANGEROUS LOAD-DO NOT USE!
+08.0  119    82.08   3258    4715   82451  11063     99.2    0.967  !DANGEROUS LOAD-DO NOT USE!
+10.0  121    83.60   3323    4903   88866  11157     99.5    0.937  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba    110    76.00   3153    4414   74406  10416     99.9    1.015  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    110    76.00   2803    3490   50369  10012     89.8    1.199  

Does not surprise me any book velocity is always over rated IMHO.

That translates to a 7.2% variance from book to reality. Most book loads are 26" barrels, in indoor climate controlled ranges with precise chrono placement, no or little air currents and overall optimal conditions. In my experience, RL19 is very slightly temperature sensitive, so 40 degrees can mean 40-50 fps. Powder lot, primer lot, case wall thickness, chamber tightness, bullet jump, throat depth, moon phase, elevation, barometric pressure, sun spots, cosmic rays, gravitational pull of a passing 747...all factors. Seriously. I could plausibly show the physics impact of any of these. It'd be a lot of bs, but it'd be mostly plausible bs.

Basically, what I'm saying is there are a LOT OF VARIABLES. Any or all or some would add up to a velocity difference. And it's a half inch rifle! 3000fps isn't going to make it that much better. It's already pretty darn good. Pushing a 200gr 338 that fast out of that case is pretty impressive. Shooting it 1/2 Moa is more impressive. Tweaking slightly up, or down might get you a bit more accurate, but not necessarily. It sounds like you're pretty darn close to the sweet spot. Ignore the book velocity numbers. You'll sleep better.

Sounds like you're good to go!

Chronographs are tricky and sensitive..I always fire 10 rounds, take out the high and low and average the 8..It seems to be the best method..

My hunting load of RL-19 and the 225 Nosler Accubond gets me 2913 FPS and cases are good for at least 10 reloads for sure and mostly 14 to 16..If I were to anneal every firing they would last forever. I can duplicate that with RL-22 and it some guns its the best powder.

Change the bullet, primer, case make, and all the above will probably change to one degree or another, consistency is the key to good performance..

I don't have the data handy but one of my favored loads for the 338 WM is Rl 19 with a Nosler 210 Partition.