Parker DHE 12 ga Damascus Barrels

[Big Friend Ten (BFT)]

Jent,

What pressure was the ammo that bulged those three #1 Frame Damascus barreled Parkers?

The term "Light Target Load" seems to denote low recoil and a lower weight of shot rather than low pressure.

Be it high or low, pressure and recoil are not necessarily the same.

[Big Friend Ten (BFT)]

Greg,

Thanks for posting the barrel thickness diagram!

Toward what you stated, pressure in a contained space is constant. Since pressure is constant, the weakest (thinnest) area will rupture if the pressure is too high.

[Big Friend Ten (BFT)]

The Dupont pressure curve chart posted by Greg shows that as the wad and shot are pushed down the barrel the pressure is on a constant rate of decline. Key points of this are:

1. A load which creates excessive pressure will burst or bulge (cause permanent deformation) the area at or very close to the chamber.

2. A barrel that burst or split much past the chamber had an obstruction in it which caused a rapid rise in pressure. Since the wad and shot were far from the chamber the thinnest portion of pressure vessel (barrel between the breach and base of the wad) suffered deformation.

3. A very low pressure load can cause detonation which can damage a barrel. This is different than too high pressure caused by an overload or obstruction in #1 and #2 above.

[Wild Skies]

Originally Posted by Mark Ouellette

3. A very low pressure load can cause detonation which can damage a barrel. This is different than too high pressure caused by an overload or obstruction in #1 and #2 above.

Mark, would you please explain this? What would be considered a very low pressure load in terms of psi?

[Wild Skies]

Originally Posted by Mark Ouellette

3. A very low pressure load can cause detonation which can damage a barrel. This is different than too high pressure caused by an overload or obstruction in #1 and #2 above.

Mark, thanks for posting that from the US Army Technical Manual. I still wonder if a very low pressure load can cause detonation which can damage a barrel. Hopefully the published low pressure 7/8 and 1 ounce recipes utilizing PB powder that generate 4300 to 5100 psi that I'm using in my damascus guns aren't adding any additional risk.

[Carl Erickson Jr]

Is I understand it, Blue Dot Powder has the same pressure curve as black powder. The difference is that a much smaller quantity of Blue Dot is used to create those pressures. One of the principle reasons for using reduced loads in older shotguns is to protect the old wood. Even is the shotgun barrel has thick solid walls I would use a reduced load in an old gun.

[Big Friend Ten (BFT)]

A load can produce high recoil and low pressure or...

A load can produce low recoil and high pressure!

Excessive recoil will crack stocks while excessive pressure will deform barrels.

[Ross Alvord]

Jent, the Frame Size is a "3". This is a "Waterfowl" weight, heavier frame, heavier barrels. Don't know the barrel weight yet, but supposedly heavier than typical. Once I can determine status of barrels then maybe I have something worthy of shooting. Granted, I could alwasy put in some Briley Tubes and shoot 16ga or 20ga but I think I'll hopefully be able to shoot this one with some Vintage shells.

[Ross Alvord]

Jent, Frame size is a "2" as in the photo you attached. Also some other numbers on bottom of barrel left to right: D with a smaller 4 above, then a small c, then 4 with small 6(as if 4 to 6th power), then a 3. The barrel lug has a 2 on the bottom. I take it the "2" is the actual frame size. What are the other numbers?

Bottom of receiver has the serial number with 3 above and D below.

Although the serial number would say it is a 1906, the inside/bottom of the reciever has a date of PATD. Aug 15, 1905

[Paul P.]

Ross the large 4 with a small 6 is the unstruck barrel weight. 4lbs 6oz after assembly before cleanup, with the forend attached. The D stands for damascus steel. You are correct that the 2 is frame size. The small c and the 3 are most likely craftsmans stamps.
I have a twin to your gun. RST shells are the way I go for loads as I dont yet have the resources to reload my own. I also have 2 10ga. A damascus and a Twist that I use RST ammo in. Enjoy your Parker.