doublegunshop.com - home Forums General Discussion Double Rifles, Paradox Guns & Gauge Rifles @ doublegunshop.com 12 Bore Rifle

NT,
I have a 12 bore Holland 7 dram gun made in 1882.



The gun weighs 13lbs and the barrels abit over 9lbs. I use brass cases but have used plastic in the past. I have a period mold which casts both ball and a short conical in the .740 range. My gun is proofed as a 12 and has a groove diameter of .736. I too would be interested in seeing photos of your Holland. Here is a reprint of Frank Findlow's chart from his excellent article in DGJ on 12bore rifles.

Nick-

I seriously doubt that you're going to get anywhere with sabots and sub caliber bullets with this rifle.
So much to the point that I'd never bother with attempting that with the rifle myself whether it were mine or someone else's rifle.
Interior ballistics, pressure curves...
Stick to the right stuff here, Jeff Tanner will make you a custom roundball mould for under $50.00 USD and ship it to your door.


I'm interested to see photos of your chamber casts, really good photos -- contrasty enough to be able to clearly see the condition of the chamber walls on your castings.
As noted, a seven dram rifle will be much heavier that what you have there.
Three inch chambers on an H&H twelve bore rifle lead to that assumption, but considering the overall weight my sense right off the bat is that it's not a seven dram gun.
I'd like to see photos of those barrels, the barrel flats including all proof marks, and the action flats including all of the proof marks, as well as with a ruler laid on the barrel flats justified to the standing breeches.
I wonder if someone at some time has gone in there and lengthened the chambers to clean up a pitted throat.
Also I'm curious to see if it was set up for paper or thin brass cases.

On rifling twist, you'd be surprised at how many high quality brit bore rifles *set up from the factory for roundball* have 'too fast for roundball' rifling twist rate -- and shoot beautifully with roundball nonetheless.
What is the rifling profile?
How many lands?
What is the bore diameter?
Is the bore/groove the same at the muzzles as it is at the breech end?
Compare right and left barrels too, chances are that they're not exactly the same.
Are the barrels actually original equipment?

Photos please!
Can't wait to hear and the specifics on this rifle.



--Tinker

With proof marks of 13, this most likely was a "paper case gun". There may be loading/chamber information on the Holland ledger page and you should request it from Holland & Holland London.

Thanks again for all the replies.

PM, That's a great set of data I'm saving those pics for sure. Much appreciated.

Tinker, I'm just trying to get off easy with the whole sabot thing. I guess we'll have to go with the mold and do it right. It's a hefty gun, but if 9 LB barrels are typical for a 3" gun than this one isn't even close. That's a lot of extra iron. I don't know much of anything about how much a rifle should weigh based on caliber except that dbl rifles are heavy and bore rifles heavier still. All I can reference is what little experience I have shooting big bores.

You'll have to coerce the Right Honourable DT/CC about pictures as the rifle is currently residing in the Cape Neddick Gun Hospital---Dr. Trevallion , Attending. Otherwise I'll see what I can do in a month or so when I'm back in the neighborhood.

Thanks again to all for the info.

Nick

Here are photos of rifle with 3 " chamber guage.

Older Doc-

Much thanks for posting the image, still my curiosity isn't satisfied.
Do you have the rifle in your posession or can you comment on some of the questions I asked above?

Perhaps the owner of this rifle (you?) will get in touch with the maker and get their perspective on the service load.

Can you post images of the rest of the rifle?

Again, thanks!



--Tinker

I don't have the letter nor the gun. Inthe process of getting the letter.

Older Doc-

Thanks for the answer.
I'm very much enthusiastic about these light sporting bore rifles.
Please do post back to this thread when you can share more information about this rifle.

Is it yours?
Will you be hunting with it?


--Tinker

It is mine and I do want to shoot it when I can configure the right loads. Enclosed are some photos that I do have.

Older Doc-

It seems you've found a very nice 'walking around' bore rifle.
I relly do enjoy my light 16 bore double rifles.

This is an image I've shown on the site before, I include it here to encourage you to your first day of load development.

First shots in likely over 100 years, this is a light european hunting rifle...





--Tinker