How do I download a Maven artifact at the command line without using dependency:get or maven-download-plugin?

The copy goal is more appropriate here and it lets you specify an output directory as well (which is deprecated in the get goal):

mvn org.apache.maven.plugins:maven-dependency-plugin:2.8:copy -Dartifact=groupId:artifactId:version[:packaging][:classifier] -DoutputDirectory=[target] -Dmdep.useBaseVersion=true

mdep.useBaseVersion=true will remove timestamps from snapshot builds.