RE: bolt hard to close....
they have told you all the possible right reasons. what i do to determine bullet oal is simple. i reload a shell than i use a sharpy or a marker to color the bullet. than i chamber it than take it right back out to see if it touches the rifeling. if it doesnt, then i go back and double ckeck my cases to see if they are sized to spec. i also trim my cases every time to make sure they are right because no to cases strecth the same. goo luck.