Several comments:

I've seen Chronys be accurate, and not so accurate--though 3100 fps with a 150 in a .30-06 isn't out of the realm of easy possibility.

I would trust the rifle and chronograph much more than QuickLoad. It's an interesting program but like any computer simulation isn't reality, despite how many people seem to think it is.

Also, the "!DANGEROUS LOAD--DO NOT USE!" warning is only due to the relatively low SAAMI max for the .30-06 of 60,000 psi. This is due to many old and otherwise questionable rifles in .30-06, not because a modern rifle in .30-06 is unsafe at around 65,000 psi, the SAAMI max for several similar rounds, including the .270 Winchester.

There are several modern powders that are listed as being able to start 150's at 3000+ in the .30-06--at SAAMI pressures. H4350 is one, and there's no real reason (other than a bunch of low-number Springfields) not to boost the velocity a little.

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