The 'choke' and 'cut the barrel' debate has been very informative and instructive, and I learned a lot. I think I'd like to see a new thread post on cutting, choke, and (heresy of heresy , dare I say...) fluting. It has been well reasoned that shortening the barrel, adding a tube, or swapping out the action will all reduce weight with varying costs. I would like to orient the weight of the collective brain trust of the site back to the 'inexpensive', and 'positional pain' portions of the OP question.
On the weight issue, I swapped out a wooden Anschutz stock for a MWerks aluminum stock and the rig gained about 1 1/4lbs. So a wood stock may save you some over all weight, but check the actual weights before you go this route. If you are a careful trader, this swap may even net you out financially ahead because the wooden stocks are worth somewhat less than the aluminum, although you may not want to do this for performance issues or the marginal degradation of the original equity.
Tell us some more about your position. A photo will help a lot. I agree that 42" or 32" even is a lot of leg spread distance especially for your height. Are you measuring this, or guestimating? I am much, much, taller and tried to replicate the stance with a tape measure. At 42" more of a gymnastic event, 32" not comfortable but possible.
Where the center of gravity of the weight actually manifests itself is important. All shooting, but standing in particular, is a kind of cantilever physics problem. The muscles, tendons and bones are supposed to support and stabilize the load through conditioning and the alignment of the position. A properly constructed, sized and fitted jacket (and pants) can go a long way to helping to disperse and stabilize the load by tightly wrapping the torso, in conjunction with a well built position. This will help to counterbalance the back bend tendency of the cantilever weight. The movement of the center of gravity backwards into the arm cradle and towards the torso is part of why the bloop tube/short (or cut) barrel is so popular. Reduced bullet dwell time is another peripheral and debated benefit of that combo.
Similarly the act of shortening the butt can bring the weight further back and reduce the cantilever, but can cause other positional problems/required adjustments. This experiment however, involves no expense to you.
Back pain will not promote good shooting (as you probably have already surmised) and may ultimately derail your health. Without more feed back from you, beyond the 'lighten the rifle' aspect we are mostly guessing about the positional improvements that may be available to you. All the positional changes have the additional attraction of being free, at least until you need a chiropractor. :)
Gun weight problems
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