Hmmm. "Tweaked"? Just how so, and how bad? If bad enough to have tweaked the receiver a few thousandths out of true would it effect the geometry of the moving parts inside of it?
Something I've often wondered about: being that the receiver walls are so bloody thin and susceptible to stretching if the elasticity of the steel alloy is exceeded, if that may be a cause of increased headspace issues (especially in the early guns made before their metallurgy was changed to accommodate the .250-3000)? Sure, the bolt nestles firmly against a big blob of steel in the back but what's that steel ultimately supported by - the receiver walls. Purely an academic question as obviously practically the rifles have chugged along without breaking a sweat for 100+ years. I sure would like to examine a 1899/99 that failed due to a horribly egregious overload or tested to destruction with increasingly stiffer loads, just to see how/if the receiver walls reacted and/or failed.
I've often said the 99 receiver, while hell for stout, has to flex/stretch a lot microscopically at the instant of discharge and might possibly explain why brass life can sometimes be less than the same brass fired in a tightly breeched bolt gun or single shot. Try as we might otherwise, all steels are limited by their tensile strength and elasticity.
