Michael:
I applaud your effort to change the parlance. You are right on in your assessment of the popular terms - they stink!
The problem with "high tech rifles" is that, like "assault rifle," it doesn't convey any intrinsic meaning. Therefore, it is a term susceptible to highjack. I can hear it now: "The .22 I had growing up and my dad's 12 gauge weren't high tech, you don't need high tech guns to shoot pop cans and clay pigeons. High tech guns use technology to kill people. Period." Arrrrg.
How about describing the gun in concrete terms? Either by model (AR-platform) or function (gas-gun/semi-auto). Those are less fungible terms.