shooting way too high

Got great grandfather's 99 in 303 from my dad. Put together some reloads for them and it's off the target high at 100 yds, at least 12". Got my first buck with this 35 years ago and find myslef wanting to hunt with it again. I remember it being high with winchester silvertips, but not this high. Rear sight is as low as it goes. Front is fixed height in dovetail. What have any of you done to remedy this? Taller front sight I presume. Any off the shelf fixes?
I plan to put rear sight in its middle position and shoot at 50 yards. I will then calc what I need to raise the front sight.
Thanks

You're on the right track.

What reload recipe is the OP using? How many shots did he take to find the group 12” high? Depending on bullet weight and velocity the POI can be pretty high or pretty low. But if it was shooting high with factory ammo years ago then changing one or the other sight will fix it.





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99 K is right on, sights are the key, you need to find out what was the original sights, often are changed for some reason and did not fix.