Re: Second opinion please.
The OAL listed in the manual is normally the SAAMI standard for that cartridge. Ammo loaded to that length should function safely in 99.9% of the firearms chambered for that cartridge. The optimum OAL for a given cartridge in a given firearms may be longer, or shorter, than the SAAMI standard. Things like chamber throat and magazine box length come into play, and normally, only you can determine what's right for your specific rifle.
Some bullets like to be seated very close to the rifling; some want to be seated actually engaging the rifling. Some are more tolerant of a 'jump' before they engage the rifling. Jamming a bullet into the rifling will increase pressure, which needs to be taken into consideration when working up a load.
If you assembled your ammo in accordance with the manual, you should be just fine.