I'm shooting an older martin cougar speedflite at about 70 lbs. My question is can I back out the limb bolts a bit & not need to retune?

Also, how far do you suppose I need to back them out for a 10 lb reduction?

Thanx,

If you back out the limb bolts you will have to make some adjustments.
you will have to back them out probably 4 to 5 full turns for 10 LB reduction but it wont hurt to put the bow on the scale after 3 full turns to see where you stand, do not turn out any farther than 5 full turns unless the manufacturer otherwise states you can turn them out farther.

Thanx,

So if I do this I'll need to reset the nocking point or should I move my rest. Centershot shouldnt be affected, correct?

Thanx again.

If you back out both limb bolts exactly the same you shouldn't have to re-set the nock heigth. Your pin gap will widen because of the reduction in speed. Most bows will reduce / increase 3-4 pounds per bolt turn. Be carefull when backing out the bolts, 5 turns out should be ok if the limb bolts are bottomed out.