Well as you asked
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I don't think about the .260 at all. You see I have two rifles chambered for the 6.5x55 Swedish cartridge so there is not need to even think about the .260! Now the 6.5x55 can use bullets as light as 77 grains in fact I have some factory Norma ammo loaded with 77 grn soft points and some Jagdtmatch with 77 grain RN FMJ's. I did try some 85 Grn Sierrias HP's but didn't stumble on a load which gave me good accuracy so stopped working with them as I already have a good load for the 100 grain Nosler Balistic Tip which is light enough for anything I wish to shoot with it and loads for 129 grn, 140 grn and 160 grain bullets so it covers most bases
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One of the rifles is a sporterised Swedish Carl Gustave (commercially done) with a new short barrel. I had the bolt handle changed to the one you see for better clearence of the scope and easier use:-
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I aso re-shaped the trigger to bring it further back in the guard. The other rifle so chambered is this modern Mauser Obendorf M96 Slide bolt :-
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This one seems prefer 140 grin bullets to the lighter ones but then again it might just be that I have not discovered the load it likes with the lighter bullets. I do try to keep the loads so I can use them in either rifle.
So you seen I have no reason to even think about the .260 Remington as there is nothing it can do which the old 6.5x55 in a strong modern action cannot
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as for loading light and heavier bullets yes of course it can be done especially with the Swedish cartridge and I suppose the .260 should be able to handle them as well although I have experience with it as I explained but if you do so it's unlikely that the sight setting would remain the same of course. So if you wish to go that route then may I humbly suggest QD mounts and two scopes so one may be set up for deer and one for varmints
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it would save a lot of time re-zeroing and mean you can spend more time hunting or simply practicing.