The old rule is 1X per 100 paces. Seems to work for most applications. 6X if you need FOV for moving targets (hunting). 10X for grins. Anything over 12X starts to run into optical limitations unless you really start to spend hugely. Fixed optics are far more stalwart than variables. The SWFA's have had ham-fisted brutes crank 1,000's of moa/mils into the erector with a flawless RTZ and drown 'em in frigid rivers without fail. They track equally well with stupid amounts of "up" on the erector. Many of the spendy Euro optics can't hang. 10 mils on the glass and 20 or 40 moa on a rail will get you to the next ZIP Code. Just dial up JBM ballistics and add a LRF. It's so easy to connect POA/POI dots even you know who could do it..... *grin*

ELD's are javelins not beach balls. Good guess. There may be more bullet options at 30 cal. but they get pretty heavy for a given B/C with the requisite increase in case volume and costs. Savvy? If not, play with the JBM calculator cited above, comparing your 300 cannon to the diminutive 6BR squirting fast-twist 0.6-ish B/C's for grins. It's physics. Set the output to "mils" to correspond to the recommended optic's MQ reticle. There are advantages to going toward a 6mm as it is far more forgiving on the shoulder and wallet. I don't trust the opinions of those that shoot BMG's.... *grin*

A Blue progressive is better for high volume pistol ammo or 5.56. A good single stage along with a Redding powder thrower/dies will handily spit out loads of quality rifle fodder for most uses. Take a gander at the Forster Co-Ax.

Go to Greg's website and look up his current pricing for the bolt bush fix. Send him your bolt with a PMO for the work and you'll have it back inside 2 weeks. He has a dedicated lathe set up for the work. If it wasn't obvious in the vid, he bushes your bolt face and turns down your OEM pin. He also has his own pins. Again, visit his website and wander around.

Have fun popping primers....