The swing builds rhythm and momentum for the delivery. How far you swing, what gravity takes over and why you save strength instead of accelerating.
The swing is the part before the delivery in which you move the stock like a pendulum back and forth beside your body. The honest answer to "What good is that if I only have to let go anyway?": it puts you in a rhythm, stabilises your body and prepares the actual attempt. In clubs it is sometimes called "Klingeln"; I did not find that term in the teaching materials I read, so this is what the textbook calls "swinging".
The BÖE textbook gives a simple formula: the more stable the swing phase, the more stable and precise the main phase, and thus hit rate and sense of achievement [1]. And there is a number that limits your swing: with the upper body as the axis the stock is swung at most 70 degrees forwards and at most 70 degrees backwards [1]. 70 degrees is a little over three quarters of a right angle, clearly less than "stock above the head".
The textbook expressly states that ice stock sport loads one side of the body and that stability must be worked on early [1].
Swinging is preparation, not performance.
Entry criteria (practice standard):
Before you swing you stand stably. Knee joints slightly bent, hips and lower back in a neutral position (no hollow back, no round back), shoulders tensed slightly back and down, head neutral [1]. The free hand balances the swing [1].
Milestone: You stand stably for 20 seconds with the stock in your hand.
The stock swings like a pendulum back and forth. To achieve this you accelerate it a little on the downswing [1]. You save strength in the preparation phase [1].
Milestone: You swing five times evenly back and forth without the rhythm wavering.
Take the upper body as the axis: forwards at most 70 degrees, backwards at most 70 degrees [1]. On the last swing back you may go somewhat higher: acceleration rises to get higher backwards, but for beginners at most 90 degrees to the upright upper-body axis [1].
Milestone: Your coach confirms that your swing does not exceed the limits.
After the stock has been brought back with a little more acceleration, it swings down only with the help of gravity. Beginners do not accelerate it further downwards. The textbook describes it as an "elegant dropping" and laying down [1]. Only advanced players additionally use muscle force [1].
Milestone: You swing ten attempts without any extra acceleration downwards.
You breathe loosely, without forced breathing or holding your breath [1]. On the last swing back the upper body bends slightly forward to lengthen the swing path [1]. The bending should only happen on the last swing up, not already in the preparation [1].
Milestone: You bend only on the last swing up and breathe loosely while doing so.
Ice stock sport loads one side of the body more than the other, and the textbook says exactly that: work on stability early, with balance, coordination and stabilisation exercises that do not overload [1]. A trick the textbook names: if you repeatedly build swing phases with the "weaker" hand into training, that raises stability on the "good" side [1].
This guide explains and motivates, it does not replace supervised training.
Swing a few times with the weaker hand without delivering, just for the feel. The textbook calls it a psychological trick that raises stability on the good side [1]. Also: count quietly, for example "one, two, three", and deliver on the third swing so your rhythm is the same every attempt. The counting is practice, not a study finding.
Forwards and backwards at most 70 degrees, relative to the upright upper body as the axis. On the last swing back for beginners at most 90 degrees [1].
No, especially not as a beginner. The stock swings down only with the help of gravity. Advanced players can additionally accelerate with muscle force [1].
Not in team play. Running ahead with the stock in hand or pushing the stock forward makes the attempt invalid [2]. In the target competition too, you make the attempt from the delivery spot (if the player is not standing on it, the attempt is invalid) [2]. The distance competition has its own rules and a different technique, which is a different discipline.
Loosely, without forced breathing or holding the breath [1]. In distance sport breathing is used differently, which you learn in the club.
In club slang the swing is sometimes called that. The term does not appear in the teaching materials I read; the textbook speaks of swinging [1].
Keeping Direction in Ice Stock Sport: The Stock Should Run on Your Line