Have used 748 a lot in the .308 with Hornady 150 grain Spire Points. Have used this combo since the early 80's and it is an excellent powder for 150's.
Depending on your rifle 48 to 49 grains shoots great and will give somewhere in the 2800 fps range in 20" to 22" barrels, i.e. between 2800-2900. 49 grains can be too hot in some rifles (although I have gone to 50 in one particular rifle I don't recommend it) To be safe start around 46 grains and work up.
Gunnery, gunnery, gunnery.
Hit the target, all else is twaddle!
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