Other than the .408 CheyTac and 40-70 Sharps, what other calibers use a .408" diameter bullet?

I have a box of Barnes .408" 400gr X bullets, with no home at the moment. I guess that means I need to buy a gun to shoot them.

Tony

Some 450/400 rifles could use them.
Slugging the bore would tell if that is the case.

You can use them in things having a .410 groove; it won't hurt them. And as stated, some 450-400s have 408 barrels.
I use only .410 for 400 Whelens. And 40-65s. I have also made 404s with a .410 groove; makes a good round and I don't want a .423 rifle. But that is another story.....
Point is that you can use .408 bullets in several rifles.

.40 Newton

My 450/400 3" E Green and Sons and my Greener 450/400 3 1/4" both are .408.

Mostly 450-400s, both 3" and 3-1/4, mostly the 3-1/4 has been my experience..