Properly Loading Your Speargun - Factors Involved
Properly Loading Your Speargun - Band Size, Load Assists, and More
Properly loading your speargun can be a challenge. There are a couple techniques and tools that make loading a speargun easier. There are also different material option of bands that can make loading your speargun bands easier or harder.
Proper Loading Technique
Most spearguns can be loaded using proper technique rather than brute force. Trying to load a speargun through brute force alone can result in some challenges or injuries. Loading a speargun requires a few muscle groups that are not the most common exercises one would do in normal life (however, you can work out for it in the gym with shoulder and back exercises). See this video on proper speargun loading technique for rear handle spearguns.
Band Length
The band length is the biggest factor that makes a band difficult to pull back. The optimal stretch for a speargun band is 350% stretch. The formula to find the length your bands should be is:
This formula applies to all the different diameter bands. Making your bands stretch more than 350% doesn’t dramatically increase the power you are adding to your spear shaft. Making longer bands reduces the power to the spear shaft. If you reduce the power of your bands too much, you won’t be able to shoot through your fish.
Band Diameter
There are several thickness band options available for your speargun. The thickness of the bands determines the amount of stored energy in them. 9/16” (14mm) bands store approximately 90 pounds of force per band. 5/8” (16mm) bands store about 110 pounds of force per band. 3/4” (19mm) bands store 130 pounds of force per band. The challenge with bigger bands is that they take more force per band to load. Some divers prefer to have a larger number of easier bands, other divers prefer one hard to pull band. Past injuries or surgeries may impact your choice of bands. Make sure your speargun is designed to accept your band diameter of choice before purchasing. Some muzzles may not be able to accept some larger band diameters.
Small ID Bands
In the past few years, Small Internal Diameter (ID) bands have increased in popularity. The idea behind them is the bands have more rubber inside them, which adds more stored energy to smaller bands. This makes the bands a little harder to load than the standard ID bands, but many divers feel their spear accelerates faster as a result of the smaller diameter bands.
Load Assists
Load assists are particularly helpful if you have had some type of shoulder injury or surgery. They are also beneficial for loading very long spearguns or roller spearguns. The idea behind them is that you can hook the load assist to the band’s wishbone and load the load assist to the spear notch. Then you can finish the band load with the band already partially loaded.