What a treasure! The gun clearly gave your great grandfather, and grandfather, many days of joy afield. A $2000 - $4000 Turnbull or Dudley like new restoration will remove the evidence of your family's holding and using the gun. Be aware that any work done wrong will significantly diminish the value.
It does need to be refurbished, checked and cleaned internally by a qualified double gun specialist, and the recoil pad replaced with a period appropriate pad, hopefully to be returned to the field in a younger family member's hands.
I would suggest a research letter which might document your great grandfather as the original purchaser.

Parker BHE
 

BTW, the book says your gun was made in 1915 and that's information only. It has nothing to do with the value.

Will brothers restoration

Nothing NEEDS to be done to the gun. However, if the owner wishes, there are some things that can be done to improve the overall appearance of the gun that do not include a full restoration. The outstanding de condition of the barrels is a shame. I hope the bores are still in good enough condition. That is what kills the “value” of a gun when it really comes down to it.

I always see these questions about “insurance value”. And my answer is always to just refer to the most recent edition of a blue book. Usually those values are a bit inflated from actual market values, but it is a documented number that can be provided to a company to back up your request for coverage. Speculative numbers tossed around on an internet message board do not carry as much weight.

This is all excellent advice, so thanks to all responded so far, at this point I am not sure the direction I am going to head in as no one in the family really wants it besides me. So, I am inclined to have it restored and display it. However, that could change as well. Thank you all again.

Some folks get the Insurance Value thing from watching Antiques Roadshow where they appraise something’s actual value but then give an Insurance Value of considerably more.






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I feel that you can argue and reach an insurance value with documented information after the "loss" has occurred. Companies like Gun and Trophy Insurance don't ask for values when the policy is written.

The rust on the barrels looks quite deep and ugly. The rest of the gun looks great/fine. I would replace the pad and re rust blue the barrels. I terms of value it's all about the restoration of the barrels in my opinion. If the pitting is too deep to restore the gun has very modest value. It also appears the forend lug was resoldered at some point and the LOP looks very short based on the distance from the gold oval to the end of the stock. If the barrels can be restored the value doubles. It's a roll of the dice gun but it's a B!!.

If it were mine and I knew very little about Parker Shotguns I would spend the time necessary to learn about what I actually have. You’re making a good start by asking questions here. You were lucky to inherit a high grade Parker. I would suggest you send it to Brian Dudley and have him evaluate its overall condition and let him make suggestions about the different avenues and options available to you. Please keep us posted about it. These kind of situations are fascinating to many here.

Yes I think Mike F is spot on! Many years ago I bought a real train wreck of a Parker that had suffered so many abuses (VH stock attempted to fit, hole drilled thru TG engraving to try to make it fit, split cheeks, amateur cold blued, left barrel stamped "Invincible Grade"!!) A real nightmare but some quick research and excellent help from some members here made me take the plunge. It was a really rare gun that deserved to be brought back to its original beauty. I invested a good bit of money in it and sent the required work out to the best gunsmiths referred at the time. Turned out to be an 1897 AH Grade Damascus 16 ga. 26" on a 0 frame, originally ordered by a real estate attorney in Tidewater VA. One of only 2 documented in Parker records as having been built in that configuration. Oh what quail tails it can tell!!