"The ogive" and twist rate.
The longer throat length (specI 0.064) to (specII 0.105) and a 1-10, 1-11 and 1-12 twist rate.
I like the 1-10 I shoot 115gr bullets. I Buy them at Silver State Ammo.
Bullets should be crimped. 1-12 would nice for smaller bullets @ higher fps.
Like .223rem and 5.56mm Nato chambers.
To get from specI to specII is to ream out the throat. Can be done by hand with a specII reamer.
They moved to specII to shoot high pressure loads. 60,000+ PSI. To gain more fps.
Silver State sell 6.8mm brass with small primer holes so you can load #41 primers. Best to reload
Remington loads 6.8mm rounds for specI (Large rifle primers). These can be shot in specII. They maked them for the 700 Remington rifles.
Silver State loads rounds for specII should not to be used in specI rifles. Chamber pressure to high.
Hope this helps.
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