Noob

Welcome SOBX!

I can sympathize with the chest pain, I used to get that loading my RA Sparid railgun after unnecessarily "upgrading" from the standard single 16mm band to a new single 20mm band. . RA sell/sold a heavy duty strap-on chest-pad to help with that; but I made my own from the sole of thick old old flip-flop. I later went back to the original 1x16mm band set-up, which was plenty powerful enough for my modest needs.

Yes, most spearguns let you use smaller bands. Not familiar with your speargun but 2x16mm is plenty powerful enough for most uses (except perhaps blue water pelajics). Indeed 2x14mm has become quite fashionable in recent years ( and is long established in Hawaii I believe).

The other big point to consider, especially for a noob, is loading technique!! Check spearing books (Len Jones SA spearing booklet is concise but excellent , from RA). and/or YouTube for guidance; and check several, especially on loading a long speargun. The technique(s) for loading a long speargun (or for someone with a shorter reach) may be a little more involved. I think the technique is essentially to grab the bands first, then maneuver the butt of the speargun to you chest (loading pad ).

Some people use a "load-assist" (a rubber loop with a hook) nowadays, perhaps mainly for roller guns though.

Good luck. Lots of possible solutions

I used to use three 5/8" bands on guns that size, but later found that two 14mm (9/16") small ID bands were just as effective. And for years I used that technique described by Mr X- grab the band with one hand, move the butt to the chest, and then reach out and grab with the other hand. But then I discovered an option offered on Wong guns and easily used it on other brands of wood guns. Screw a line guide like the one used under the muzzle of guns to the side of the gun to use as a load assist tab. With the butt of the gun on your hip you can easily grab the band with two hands and pull it to the load assist. Then move the butt up to your chest to complete loading. I'll try to find a video, but meanwhile here are photos.