I purchased 100 pc of ADK for a new 338 RUM. Its weight was very similar to the 338 RUM Rem brass. ADK mentions that their brass may be heavier and loads should be reduced. Didn't find that with this brass when compared to Sierra's load data.
Custom reamer FB of .128" 26" 1 in 10" barrel
I used Sierra's load data for RL-25 and the 300 gr Sierra HPBT Matchking. Sierra listed powder charges to get rounded velocities like 2400, 2500,2600 etc. Their starting load is 76.9 gr, The following loads are what I tried:
77 gr 2420 fps / Sierra 76.9 gr 2400 fps
80 gr 2501 fps / Sierra 80.6 gr 2500 fps
82 gr 2566 fps / Sierra no data
84 gr 2618 fps / Sierra 84.4 gr 2600 fps
86 gr 2675 fps / Sierra no data First shot had no issues, second shot had a mild clicker to open bolt.
88 gr 2733 fps / Sierra 88 gr 2700 fps Only fired one shot some resistance in opening bolt, a hard clicker
Stopped at 88/ Sierra listed a max load of 89.9 grs for 2750 fps
Accuracy load with my rifle uses 85 gr for 2618 fps.
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The brass was very similar in weight with the flash holes drilled/no inside burr.
I would purchase more ADK brass in the future.
ADK?
