Greetings.
I am well aware that AR2206 has been out of production for 25 years or more. I used it up to about 2011 when I ran out and changed to AR2206H. About 4 years ago I ran some comparative tests in the .308 between AR2206H and the then new IMR8208XBR. Just for fun I salvaged some AR2206 and included that in the test for the 125 grain Speer TNT. Velocities for IMR8208 and AR2206 were near identical as commented. The also agreed with the book velocity.
Last year I started some loads for my heavy barrel .223 for F class shooting. The rifle has a 12 inch twist so the heavies were out so I tried the Hornady 60 grain V Max with AR2206H and BM8208. Velocity for the AR2206H was right on for book data but BM8208 gave way low velocity. So I did a bit of checking. The Hornady data and Pet Loads from Handloader both showed much higher loads to achieve the same velocity and agreed with my results. So the Hodgdon/ADI and the 2 other data sets are at odds with each other. Neither of the two lots of powder is old and it is evident that the speed of one or both powders has been slowed since the Hodgdons data was shot. Why this happened I don't know but happen it did. This is not the first time that my chronograph has shown significant differences in powder speed and likely won't be the last. This is relevant as it is from current lots of powder not old ones. It is the Hodgdon data that is outdated,
Regards Grandpamac.
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