Using a Big Shot
Proficient use of a throwline can take many years of practice to master .
Whilst there are many advantages to using a throwline well , including the ability to use the throwline to advance a climbing system to a higher branch once in the tree , and the reduction in equipment that must be carried , most rescue teams will not have sufficient training time to become proficient with this skill .
The use of a Big Shot or similar linethrowing device can hugely increase both the range and accuracy of line setting .
To use a Big Shot , the throwline and throwbag should be prepared as described on the previous page . Ideally , the throwline will be flaked into a folding cube or similar , to ensure that it pays out smoothly when fired and does not become tangled in twigs and branches on the ground .
If needed , the throwline can be flaked onto a tarp or similar , prior to being used .
The user of the Big Shot should set up on firm ground slightly further from the tree than the cube or tarp . This ensures that the line will be away from the user when it is fired .
The Big Shot can reliably achieve shot heights of 50m with practice and light bags . Ensure that the elastic is inspected before use and that the user wears eye and head protection in case of elastic failure . Warming up the elastic can help to increase range .
Some models have an optional trigger mechanism . It is usually possible to achieve higher and more accurate shots using this mechanism , as the elastic can be brought to the maximum possible tension , then fired by one person who can take the time to aim carefully .
It is usually better to aim high and manipulate the line into the target union ( see following pages ) rather than to try and hit a specific tight fork through a dense canopy .
After taking the shot , allow the bag to run to the ground . Trying to ‘ catch ’ the line and bring the bag up short to save time may cause the line to wrap around a branch or get stuck as it is pulled back through a tight fork . It is usually better to let the line continue running to the ground , then make a decision to either :
1 . add additional throwbags for extra weight before pulling the line back to the target fork ,
2 . remove the throwbag from the line and pull the line out of the tree , or 3 . use double-bagging techniques to isolate the fork .
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