coyote hunting in mass

[Coyote33]

I saw the droppings in the middle of one of the atv trails behind my house...

If all goes as planned, one of the DM lowers from the current group buy will be built up as a 'yote rifle...

Here ya go, # 1 or #2:
http://www.accuracysystemsinc.com/ar15_conversion.php

or the first 3 here:
http://www.ar15barrels.com/calibers.shtml

 

[Viper22]

Here ya go, # 1 or #2:
http://www.accuracysystemsinc.com/ar15_conversion.php

or the first 3 here:
http://www.ar15barrels.com/calibers.shtml

I was already thinking of a .204 Ruger upper.

How much of a difference is there between .204 Ruger and .223 in cost for ammunition and in purchasing a complete upper? How about ammo availability?