No
Usually not. A BB is .17 caliber and a 6mm pellet would be .236 caliber. That means that a 6mm BB gun would be imaginary. There are .17 cal. pellet guns and there are .22 cal. pellet guns. You could drop a BB into a .22 cal. pellet gun and it would probably be ejected if it didn't roll out the barrel first. Always read your owner's manual and become familiar with the recommended ammunition and operating instructions.
Somwething like this, 223 or 224 diameter bullet is 22 cal. 243 or 6mm is 24 cal 257 is 25 cal 308 is 30 cal and so on. There are some bullet diameters that cross over the caliber lines.
Yes. The same brush you use to clean a .223 can be used for .22 LR, .22-250, .222, and other cartridges in that same calibre range.
35-300 usd
The 22 is slightly larger than the .177 cal. The 177 Pellet is almost the same diameter as the .175 BB.
6.35 mm is equivalent to 25 ACP
You will need 6mm plastic BB's. These can be gotten at most sporting goods stores these days. *There are also airsoft guns that shoot 8mm BB's. These are quite rare to see in the United States, so I'm betting that your gun is 6mm. .177 cal metal BB's or .22 cal metal BB's won't work in your airsoft gun.
No
No
Marlin 81
Stevens 416 is the same