XCR 5.56 to 7.62 and back?

[matai]

I'm thinking about buying a Robinson XCR in 5.56x45mm and then buying the 7.62x39mm kit. It's the 7.62x39mm that I really want, but to have both it's cheaper to get the 5.56 first.

My question is, if I'm using Troy DOA sights and a Trijicon TA33 or TR24 scope, will I be able to go back and forth between calibers and figure out how to re-zero the sights without shooting?

In other words are there methods to just figure out how many "clicks" difference there are between the calibers?

Any other advice on this setup? I'm thinking it'll be a mid-weight "battle rifle" / hunter type with a UBR scope, heavy 16" barrels and 4x or under scope.

Thanks

 

[ny32182]

Different barrels will not shoot to the same POI, but the same barrel, when removed and replaced, should be very close. Therefore you will have to remember how many clicks in each direction to adjust your sighting systems when swapping barrels. Or make some witness marks.

 

[anthony-white]

I would do the witness marks method or create a "range card" for the swap.You can tape it to the gun case then tape over it to protect it from damage. I would adjust the scope first, then if the sights co-witness and are visible with that magnification; move the irons to the scope.