I picked up a stock as part of a trade and it's alot different than my other commercial M1a stocks. It's on the chubby side. I refurbished it with teak wood oil because it had nice grain and I think it's birch (but I would like the wood expert's weigh in). Is there a reason for the extra wood? Its extra thick all over compared to my other wood. Did a search but didn't find an exact answer. Would like to here what everyone thinks..