Mate, don't even worry about this! The Paradox-type guns had bullet-jump of 24-inches, and still managed way-better than 6-inches at 100 yards!

Admittedly with jacketed bullets, the Weatherby and Mannlicher Schoenauer have set global accuracy standards for decades, with the bullet completely leaving the case-neck before it contacts the rifling!

The only things a long bullet-jump will decrease are chamber-pressure and recoil! (provided the projie is correct diameter to 'seal' in the throat).