I ended up with a heavy barreled model 70 through a trade deal, and I hoping some of you more knowledgable Winchester guys can help me with some information.

According to the serial number it was made in 1960, it has a 26" heavy barrel and is chambered in 243.

I guess I have three main questions:

1) the barrel is drilled and tapped at the front, and above the printing on the barrel. The spacing and placement of these holes doesn't seem right for sights - is this factory, and if so for some weird scope mount or?

2) the stock doesn't have a wide "varmint/target" forearm, but rather a forearm that looks like a typical sporter. Is this normal or was the stock swapped out?

3) and lastly are these heavy barrels common? Uncommon? Sought after, or avoided?

Excuse the picture, I'm not sure why the wood looks so shiney, it isn't in the flesh.
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