View Full Version : Forcing cones
John Keegan
06-05-2015, 05:34 PM
I just took my recently acquired 1901 Vulcan 12 gauge. As I was getting ready a friend came by, looked down the breech and said, "Someone took the forcing cones out."
A bit of reading told me that many guns of this era did not have cones but shoulders as mine does. Some said that using modern ammo without a forcing cone would loosen the hinge pin. Others said adding a foxing cone could create excessive pressure.
Does anyone have any info or suggestions about the desirability of forcing cones in a 114 year old gun?
John Campbell
06-05-2015, 07:46 PM
Sir:
Forcing cones are a good thing. As long as the creation/elongation of them does not thin the barrel walls too much ahead of the chamber. This is the primary danger in old doubles because this is where pressures are the highest.
To determine wall thickness, you need a wall thickness gauge. A good gunsmith will have one. And will be able to advise you on safety.
The function of the cone is to "funnel" the shot and wadding into the bore as they leave the cartridge. The presence of a cone does not raise pressure. It lowers it. What generally loosens an old double is hot, heavy-charge modern cartridges. Americans love them. Old doubles don't.
Read some of the McIntosh "Shotguns and Shooting" books for more.
Sam Ogle
06-06-2015, 04:51 PM
Wonderfully said Mr. Rise: Older guns don't need the pounding, nor do gentlemen shooters. The best sporting clays score I have shot with my 12 Gauge was with 7/8 ounce loads. And, yes, they kill pheasants stone dead too.
John Keegan
06-07-2015, 11:40 AM
Thanks for the feed back. I have ordered "Shotguns and Shooting."
As with most things on the internet, it is always best to check the information. I am glad to have this forum as a resource.
JCK
Linn Matthews
06-07-2015, 12:17 PM
Please help me a bit. Relieving forcing cones does reduce pressure and lessens recoil--right?
Dean Romig
06-07-2015, 11:13 PM
Not significantly.
Parker's chambers were generally cut 1/8" shorter than the length of the shell recommended for use in them. This 1/8" provided for a better gas seal when the paper shell opened into the cone rather than stopping exactly at the shoulder of the cone.
You might expect a pressure rise of approximately 100 p.s.i. due to this design.
Again, not significant.
John Keegan
06-08-2015, 12:04 PM
Does anybody have any suggestions on loads for pheasant or grouse. I would like to take my VH to the field this fall but want to make sure it comes back in one piece.
John Campbell
06-08-2015, 12:29 PM
Any load that throws 1 0z. of shot at 1200 fps or less.
Bill Murphy
06-08-2015, 12:31 PM
Are you saying your gun has square edges at the front of the chambers? That is not the way this gun was made.
John Keegan
06-08-2015, 12:39 PM
There is a distinct ring inside the chambers rather than a taper.
Dean Romig
06-08-2015, 01:34 PM
A friend came by, looked down the breech and said, "Someone took the forcing cones out." A bit of reading told me that many guns of this era did not have cones but shoulders as mine does.
Parkers made with 90 degree "shoulders" were intended to shoot brass shells with no crimp. It would be extremely unusual that a VH would have been made this way, but not impossible.
Some said that using modern ammo without a forcing cone would loosen the hinge pin. Others said adding a foxing cone could create excessive pressure.
Not so! I have 2 D-Grade lifters chambered for brass shells, one a 12 and the other a 10 and I shoot modern (RST) ammo in both without a care.
Does anyone have any info or suggestions about the desirability of forcing cones in a 114 year old gun?
The gun is what it is and unless the chambers have been lengthened and by doing so, the cones have been removed which raises serious questions about the wall thickness at the front of the chambers, can probably be used with modern ammo of the appropriate length and pressure.
Rick Losey
06-08-2015, 05:24 PM
rings like this
http://parkerguns.org/forums/picture.php?albumid=588&pictureid=7190
John Keegan
06-08-2015, 05:27 PM
Yes, that is what they look like.
Rick Losey
06-08-2015, 05:43 PM
BTW - your avatar - a napoleon 6 pounder?
might want to lighten up on the charge :rolleyes:
:rotf:
John Keegan
06-08-2015, 06:03 PM
It is a full scale reproduction mountain howitizer. The bore has a steel sleeve and we fire a 3# lead ball with 4 oz cannon grade blackpowder. Fortunately in Arizona there are a lot of places where you can fire off a cannon.
Eldon Goddard
06-08-2015, 10:24 PM
It is a full scale reproduction mountain howitizer. The bore has a steel sleeve and we fire a 3# lead ball with 4 oz cannon grade blackpowder. Fortunately in Arizona there are a lot of places where you can fire off a cannon.
How can you not love this country? John I do not live to far from Peoria can I come see your cannon. Ill bring my 8 gauge.
Mark Ray
06-08-2015, 11:50 PM
The 1889 DOM DH 12 G "one " frame that i just received today has chambers that look like the photo above. When i slid in a rolled card to measure chambers, the card made a "hard stop" at that ring, instead of just binding to a stop as usual when measuring chamber length. So, that means my gun was designed for brass hulls? The depth to that "ridge" is 2 11/16ths. Thanks in advance for any info/ advise
Dean Romig
06-09-2015, 07:01 AM
... or the chambers were cut after it left Meriden. A research letter may answer that question, but probably will not.
John Keegan
06-09-2015, 11:07 AM
Always happy to show off my cannon.
Just took it out last weekend for a fundraiser for the Boy Scouts. Generally we shoot the big gun then some of my other antiques such as .45-70 Springfield, both infantry and cavalry model, '03 Springfield and M-1.
Bill Murphy
06-09-2015, 05:21 PM
If your chambers actually have 2 11/16" chambers with square edges, you should probably have the square edges rounded a bit, or punched with a 2 3/4" chamber reamer, which solves all problems. Maybe someone here has such a reamer to lend. A member lent me a 28 gauge chamber and rim recess reamer that successfully converted two guns to usable condition.
Mark Ray
06-09-2015, 05:26 PM
Good idea, will pursue that!
Thanks
John Campbell
06-09-2015, 05:33 PM
If you have not done this work before, it is most wise to pay a qualified double gunsmith to do it correctly. The cost is most reasonable. And there will be no regrets.
Mark Ray
06-10-2015, 03:37 PM
No worries there.....same reason i dont tie my own flies! If Imwere to attempt that, i would probably end up with 3 1/2" 10GA. Chambers......Nope, Sir Kirk Merrington will get that honor if required!
Thanks all for the input.
alan kirchner
06-10-2015, 10:56 PM
anyone want 2 12 gauge forcing cone reamers contact me thru pm you can have them for the shipping
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