I don't know just what the Brnesdale limbs should max at on the ShadowCat, but it would seem they should be 55# or 60#. The grey stripes on the edge and 135 deflection number do identify them as Barnesdale limbs.
Now for the Martin limbs. I'm almost positive that with the red stripes on the edge these are 2010 4 laminate limbs. If they were Power Tuff limbs they would be marked 3HP. With 2.0 cams the 3H should max at 60#. Most max just a bit higher so yours pan out to specs. What happens when you put the 1.5 cams on is that, being smaller, it takes more leverage to roll them over. That's why they max so much higher. It's normally about 10#.
If you want to drop the weight you'll have to get new limbs. With Martin's deflection codes you'd need 1H to max at 60#. Two numbers lower than what it now has. Each number coincides with a 5# change. And being as Martin now makes the Power Tuff limbs you'd most likely end up with 1HP.
If you plan on shooting lower than 60#, say 57#, and desire the bow to maxed out then you'd want 1HL (Low) or maybe 1HM (Medium). The difference between the L and the M would be about 2# to 3#.
Hope this answer your question.
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Martin/Rytera Staff Shooter
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