Remington 150 grain round nose .260”

Hello, I have come into a number of boxes of these old bullets and was wondering if someone could tell me what they would have been for? Neat bullet, they are marked and were bought as 6.5mm, and only after they were measured did I realize they were .260” diameter. The only true .260” cartridge I could find was the 6.5x70R

Hello, welcome to the forum.
As a general rule you can expect that bullet diameters are larger than the nominal caliber. As a matter of fact, most 6.5 mm calibers use bullets that have a maximum diameter of 6.7 mm (.264"). Considering you have relatively heavy (for 6.5 mm) round nose bullets that will easily set up (fill the grooves) in the barrel, there is no problem with .260 diameter.
If in doubt, ask an experienced gunsmith.
By the way, the requirement to fill the grooves is the reason why bullets are typically larger than the nominal caliber. For example, caliber .30 bullets are .308 in diameter. Note that there are many exceptions to this simple rule of thumb.

Understand, I know these would probably rattle down the bore of my 6.5x55 but I think I will just try to find a better place for them. Neat bullet though, thought it would be a good compromise in weight and shape if they were actually 6.5’s. The bullet in the middle is an original M94, I think they were called, the 154 grain fmj 6.5mm

Here is the markings on the box, looks like Remington spit out general boxes to be filled in after bullets added? Neat old boxes.

Sorry for not being clear in my response.
Your round nose bullets of .260" diameter are perfectly OK for a Swedish 6.5 mm rifle.

Yeah, I put one into the resized case and it was a slip fit in a sized neck, and though I could probably crimp it in place, I think I’ll just stick with the .264 bullets. Neat bullets though