increase blind mag capacity

recently bought a savage 116 in .338 win. mag. not that im a terrible shot but i was curious if a guy can remove the stock material from under the blind mag and extend the mag through the bottom of the stock. please inform me if this area of the stock is crucial for structure or if it would be ok to do so. any feed back would be appreciated

It's doable but, I don't know of anyone making an extended box magazine for belted cases. Not saying they don't exist, just that I've never heard of one.