A picture would be a tremendous help. There are a lot of us that have had model 70's with the tupperware stock and some of us have weighed them. The ones I've had, weighed in at around 30-32 oz's. Same same for a wood stocked classic sporter stock. Now, if you are wanting to go to a classic wood fwt stock, it should weigh less than a factory tupperware by a few oz's... Also keep in mind wood stocks weigh different, depending on wood density.. I wish I had my new XTR FWT 22-250 in hand, I'd weigh it and that would give you a good idea on how much a fwt short action wood stock weighs. A stock of that nature would bolt right up to your classic and look great..