We'll save your nickname for a clays event- I have just re-assembled a 16 PH Grade with a higher sn that your Parker- last patent date on mine is 1905, it is the King action and has the 12.5% tool steel wear plate in the barrel lug- Like yours, mine also has Twist barrels and is a size O framed gun.
The only problem with my "Project Parker 16" was a broken top lever leaf spring, thanks to (among others here) Messers R. Lewis and H. Collins, that has been replaced and the gun will be ready for test firing, once I get some BP 2.5" 16 loads- no hurry there.
Luckily mine had an intact stock and forearm- very good wood and checkering for a lower grade Parker- Always a learning curve with fine guns, I have dis-assembled a few other Parkers (mainly Trojans) and followed Robin Lewis guidelines as listed in the Forum a while ago-I have specific ground Grace screwdrivers to fit all the shotguns I strip and clean- mainly Parker, LC Smith and Win M12's- marred and disfigured screw heads are the sign of a "ham-fisted" would-be gunsmith- not good-
I did discover upon re-assembly another bit of "wisdom" as I used a long drift punch to restart the sears in the receiver after settiong the stock back into position- the dia. of that drift was slightly less than that of the actual sear axle pin- which allowed the sears to 'shift' just a bit- as I cocked, dry fired and recocked the gun with the drift punch in first- also to check the safety and push rod alignment- something wasn't right- So I gambled and with the plastic headed gunsmith hammer, tapped the sear pin in against the pressure to the drift punch- that did the trick- every worked fine-
To me, that is clear testimony as to how close and well fitted these Parkers are- so now I will turn or grind to fit a specific long drift punch to the exact diameter of the sear pin-for the next time
My 16 PH is a O frame- would the sears etc be the same if it were a No. 1 frame--? A friend has a BH 16- Bernard barrels on the No. 1 frame, believe his Granddad bought it new in 1911- a treasure--
I think you will find, as we have about 4000 members I believe, a great amount of wisdom and good advice not only on the Parkers but on hunting, shooting and the collecting and restoration of Parkers- so many models and grades and gauges- no one man can know it all. Interesting, at least to me, as I hold the late Paul A. Curtis to have been a ardent fan of the British made sidelocks that he both mentions an "old reliable" in his chapter on selecting the upland gun, but also in the glossary of his book, he uses a Parker boxlock with the visible recessed hinge pin for his example of the components of a double shotgun--
