Greetings @dannyb,
Your chronographed results are about 50 fps below those Hodgdon got with the 165 grain Hornady after deducting 40 fps for your 2" shorter barrel. As part of a larger test I chronographed 43 grains of AR2208 with the Hornady 165 grain at 2424 fps a couple of years back. After making adjustments for my 20" barrel and the extra1.5 grains of powder this works out to about 2,540 fps or 50 fps below what you got from the same charge. My rifle has had somewhere north of 1,000 rounds through it and has a long throat like yours. The CAC cases I used are lighter than Winchester. Accuracy was excellent and I wonder if your accuracy is due to a bedding problem, perhaps the stock lightly touching the barrel. If you wanted to go to a lighter projectile I chronographed the 125 grain Speer TNT with 47 grains of AR2206H in my rifle which produced 2.900 fps and decent accuracy.
Regards Grandpamac.
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