I just recently made the switch myself from a caliper release to a back tension. They're fired by drawing, settling in to your form and anchor point, and then basically you hold your wrist still and move your elbow backwards by using your back muscles to bring your shoulder blades together. If you're going to get one, I recommend one with a safety or at least a clicker (Carter Solution 2.5 for a safety and a Scott Longhorn for one with a clicker, for example). My pre-Copper John Stan has neither, and I ended up punching myself in the mouth once. The positive thing about punching yourself in the mouth is that your draw form suddenly becomes perfect. Hey, sometimes you have to let a kid burn his fingers on a stove...
Back tensions are probably the most excellent tool to practice with, because they give you a "surprise" release if you use them correctly, as opposed to punching a trigger in anticipation of the shot. Your groups will suck when you first make the transition, because it's like learning how to ride a bicycle v. a tricycle. But if you stick with it, your groups will be much tighter, and you'll learn to focus on aiming rather than worrying about when to pull the trigger.
There is a whole bunch of reading for you to do on this topic. If you use the search button at the top right corner of the screen and search for Back Tension in the General Archery Forum, you will find enough to keep you busy reading for a long time. Try to be as specific as you can in your search parameters because there are a lot of threads where "Back Tension" is mentioned.
In my opinion, you'll notice a tremendous improvement in your score once you learn BT.
A forum community dedicated to bow and crossbow owners and archery enthusiasts. Come join the discussion about optics, hunting, performance, troubleshooting, styles, reviews, accessories, classifieds, and more!