There is no one answer and I think that is understood. I don't get the reason for fast twist in the 223 as it isn't a long range cartridge and is best suited to the 40-50 grain bullets at modest ranges of 350 yards and under.

I have at least 6 223s and I just shoot 40 grain bullets in them and use it for a varmint cartridge. I do have 2 that are fast twist and I need to shoot 55 grain VMax bullets in them to get any accuracy with them.

The 223 could be the best all around varmint cartridge with the 40 grain bullets at 3600 FPS. This is an easy gun to shoot and is capable of great accuracy and will blow a prairie do into the air quite easily.

I would say that if you want heavier 22 caliber bullets, go to the 22-250 sized cartridges...

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