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Author Topic: Composition of heads for 12.7mmX44  (Read 19315 times)

27. January 2008 kl. 22:03:21
Read 19315 times

terryh


Hello again,

After 3 months I now have all I need to reload for my 12mm rolling block. I suspect that pure lead would be O.K. to use for the heads; but has anyone any views as to whether a slightly harder mix could be used? I have cast pure lead heads using a Lee 0.515" x 450g mold and will load them into 12.7mm Bertram brass cases using 50/70 dies. I intend to start off with a fairly gentle load and work up to the loads mentioned in other threads on this board.

Are there any views as to what a suitable minimum load should be?

Terry.

28. January 2008 kl. 14:29:11
Reply #1

Rotta


Hi Terry,

Congratulations on your choise of shooter - you now have exactly the same gear as I started with!:-D

You'll be fine with your pure lead bullets as long as you are able to fill the mould properly. If you have problems with bullet quality, 2-3% tin in your pot will help a lot.  The riflings of the 12mm's is pretty coarse and demand a soft bullet, so the general rule is "as soft as possible to cast".  I add 3% tin and don't notice any degrading in precision, but then again - I'm not an ace shooter either.

If it is an untested gun I recommend firing a testshot with a max load +++ at safe distance from the gun before you start experimenting with gun in hand at a target.  Better safe than sorry...

It should be sensible to start off with a load of around 50 grains of 2F and increase it from there. Optimal load is said to be around 57grn of 2F, but none of these rifles behave the same.  Some like it rather hot!;-)

Remember to fill the void between powder and bullet with some medium according to the articles found on these pages.  I don't think you can get too much powder into the case as long as the gun is in order, people are known to get good results with one casefull of 3F and a Lee .515/450 bullet.  Thats a load of 60grn+++.  Some people also speak warmly about Large pistol primers instead of the Large Magnun Rifle primers often recommended - as mentioned these rifles have their own minds...

Please share your results!:ok:

-Rotta
« Last Edit: 28. January 2008 kl. 14:29:29 by 123 »
-Rotta

29. January 2008 kl. 20:08:58
Reply #2

terryh


Hi Rotta,

Thanks for your comments.

I have cast one small batch of bullets in pure lead which I will use for now, even though they are not as sharp as I would like. I will try adding a small amount of tin to the next batch as you suggest.

I don't know when the gun was last fired, but is seems to be in very good mechanical order with a mint bore. I will certainly take your advice and try a remote test shot with 60g of powder before shooting it from the shoulder.

It may be a while before I post the results showing how the gun performs. This is because I am still waiting from the police for the variation of my firearm certificate to include this rifle. We have a perculiar law which allows us to own this calibre of gun as an antique or curio because it is considered to be an obsolete calibre. However, if we want to shoot it it must be registerd as a firearm.:crying:

Hope it doesn't take long, :ok:

Terry.

07. May 2008 kl. 8:09:31
Reply #3

Dutch van California


Even though this post is rather old I'll put in my two pence.

I've shot both dead soft muzzle loader bullets, Hornady Great Plains 385 grains. I've also shot rather hard cast 350 gr & 450 gr with no ill effects. Several hundred rounds of hard cast bullets. Not that this is preferable but they are what was available at the time. I use a card wad from www.buffaloarms.com under the bullet and have used from 55 grs to 75 grs of Fffg (3fg) with a magnum primer. Groove size is nominally .515" give or take. While I have not yet done so I think the flash holes should be opened up somewhat using svartkrut. I'd have to reference one of my books for the size but the enlarged flash hole improves ignition overall.

[Reference to smokeless loads removed by Admin.]

Dutch

31. August 2008 kl. 19:10:12
Reply #4

terryh


I would be interested in using my 12mm rolling block with modern smokeless powder as "Dutch van California" suggests, but I'm a bit worried about how safe this is with such an old gun. It would certainly make the gun easier to clean, although I can see how black powder enthusiasts would be offended at the thought. Has anyone got any thoughts about the safety issues, or any other problems associated with using smokeless powder?

Terry.

02. September 2008 kl. 8:02:04
Reply #5

Rotta


The rolling block action was never designed for smokeless powder.  Some shotguns were modified to handle smokeless loads, with special steel in the pivot bolts among other things.  I would not shoot smokeless powder in any rolling block action.  We had a nasty accident in Sweden last year and the sport does not need more of this type:

http://dutchman.rebooty.com/RBfailure.html

Stay alive - shoot black!!! :ok:
-Rotta

02. September 2008 kl. 8:19:33
Reply #6

Øyvind F.

Administrator
> The rolling block action was never designed for smokeless powder.

I agree with Rotta. The reference to the smokeless load is removed. Smokeless powder in an antique rolling block may not only prove fatal, but it is also against the forum rules to discuss smokeless powders.

So, please direct the discussion towards black powder again. :-)
Øyvind F. - forum admin
Bøker jeg har skrevet.

02. September 2008 kl. 8:49:30
Reply #7

Fabian23


> The rolling block action was never designed for smokeless powder.

That is not strictly true, later high quality steel rolling block actions for smokeless cartridges were developped.  

In the case of the actions for the original BP cartridge rifles they were indeed certainly never intended for nitro powders, stay safe and enjoy the smell of burnt black powder in the morning!
Give me iron, steel and wood!  Tupperware guns are for losers!

My website, growing entry by entry:http://www.militarygunsofeurope.eu[/url]

03. September 2008 kl. 18:41:58
Reply #8

terryh


> it is also against the forum rules to discuss smokeless powders.
>
> So, please direct the discussion towards black powder again. :-)

Oh dear, :lookaround: It seems that apologies are in order. I'm sorry Oyvind; I was unaware that only black powder should be discussed on your site.

I certainly would not have used smokeless without making extensive enquiries (of which my post on this forum formed just a part). I seem to have got my answer from both yourself and Rotta and I thank you both for that.

Terry.

04. September 2008 kl. 6:13:50
Reply #9

Øyvind F.

Administrator
> Oh dear, :lookaround: It seems that apologies are in order.
> I'm sorry Oyvind; I was unaware that only black powder should be discussed
> on your site.

No problem :) The reason is that there are a lot of modern firearms sites but few dedicated black powder sites, especially here in Scandinavia.

Smokeless in antique 12 mm rolling blocks scares me, as I have heard a lot of creepy stories from the black powder to smokeless transition era, and now lately the Swedish accident. Be careful and keep both your eyes :ok:
Øyvind F. - forum admin
Bøker jeg har skrevet.

25. January 2013 kl. 17:22:06
Reply #10

Paul Due

Guest
You can use brass from 50 alaskan or fireformed 348 brass. Dont use a 50-70 die set, but a 50 alaskan die set (from Hornady). The nominal kaliber over the grooves are .502 (my Husqvarna are .507) the kaliber over the lands are .479, so it goes fine to use .501 revolver bullets, lead or jaketed. The reason not to use 50-70 dies is that the 50-70 crartigde has a larder diameter than the 12.17x44R

                                                        Paul Due.

25. January 2013 kl. 18:00:39
Reply #11

Øyvind F.

Administrator
> Dont use a 50-70 die set, but a 50 alaskan die set (from Hornady). The nominal kaliber over the grooves are .502 (my Husqvarna are .507) the kaliber over the lands are .479, so it goes fine to use .501 revolver bullets, lead or jaketed.

For your information, this thread is five years old. :-)

Most Norwegian use .50-70 Gvt. dies, and it work just fine. And it is not recommended to use metal jacketed bullets with black powder due to excessive bore wear.
Øyvind F. - forum admin
Bøker jeg har skrevet.

25. January 2013 kl. 19:13:37
Reply #12

Paul Due

Guest
My gun is a Husqvarna model 17B combination gun, the shot barrel is 16 gauge, the rifle barrel is 12,17x44R, mine is made in 1916, bot the model was manufactured betveen 1891 and 1942 and in that kaliber. Does anyone now how long factory made cartrigdes in 12,17 mm was manufactured.

                                          Paul Due