For examples of elm stocks, just look over Yugoslavian M48 Mauser rifles. Their first choice for rifle stocks was walnut which is what the used on their pre-WWII rifles. But post war, walnut became hard and expensive to acquire so they tried others. Elm seems to have made up the bulk of them (some say "Carpathian elm" but I don't have any positive info in that detail) It tends to looking reddish like. How it's cut can make drastic changes in how it looks. Straight grained it can bear a very strong resemblance to red oak. The difference will show in cross grain cuts (like the butt stock bottom). Elm will not have the cross grain 'rays' so typical of oak.
Here is an example of one of mine. For a wide range of variations, just google image Yugoslavian M48 Mauser rifles.
Another thought occurs. They continued with elm onto their sks rifles too!
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Some have Walnut stocks like my M48B below but these are not so common. The bulk of what you see will be elm.
Anyway, I hope this helps you some.
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