I have to agree with
@Bullthrower338, Remington never chambered the M700 in 458LOTT unless it was a custom order. Even then I don't believe the action was long enough. Share a picture if you have one.
As for the great PF/CRF debate...IMO it's mostly crap. More often than not the problem lies with the one pulling the trigger not the rifle. Most of the "failures of PF actions" can be traced back to short stroking the bolt. Stuck cartridges/failure to extract due to lack of cleaning or proper maintenance. The failure list is long and I'm sure the PF haters will be along shortly to let every Army, Navy and Marine sniper since Vietnam know how wrong they are by using a PF action. I'm still looking for a person who ACTUALLY experienced a failure of some kind that can not be traced back to their own shortcomings.
The rifle can be made reliable (in most cases) regardless of the action type by a skilled gunsmith. Some are good right out of the box, some need tweaking and others major work.
Now that the rifle is good, it's time to get the shooter in shape as well. Dry fire practice, range time, clean the rifle, dry fire some more, dry fire again, range time, clean the rifle, dry fire... You get the point.