No Base line to compare with


Well-Known Member
Apr 15, 2015
Reno, Nv
Looking for some more superior Knowledge:
I have just started with the 338LM
Working on [FONT=&quot]developing[/FONT] a Load, I do not know any one here shooting a 338LM, Looked in my books/on line, I have selected 2 bullets and 3 powders to start with.
Went to the Field to do first round of testing.
All groups were sub MOA, nothing class as a Bung. I could not see any major difference in group size. all 1/2 to 3/4 MOA

Conditions: 73-75 Deg Overcast skies
Wind: 3-5 mph straight from my 6 o'clock
Elevation 6050 ft
OAL 3.70
Target heading 358deg
Lat 39.53
Humidity 38
Barrel cleaned after each group and let cool

Every thing shot in 5 shot groups
Retumbo 89gr 285 HPBT 2843 (spread 15)
90 285 HBPT 2896 (spread 17)
91 285 Amax 2935 (spread 30)

H1000 86 285 HPBT 2767 (22)
87 285 Amax 2712 (7)

RL 25 87 285 HPBT 2853 (11)
87 285 Amax 2875 (12)

I show no signs of pressure, bolt works easy on all loads:
I will re-shoot the H1000 (87)Load not sure why higher charge lower velocity

The Velocity looks a little high from books, but it was warm today and over 6000ft elevation.
I just have no base line to compare with


Well-Known Member
Mar 10, 2006
I've had great results with retumbo.
Try working up to see where your max load is and see where the best ES is. Do this at .010" off the lands.
Then do a seating depth test to bring the shots into 1 hole.

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