I have heard these action are pretty strong. How big could you go with one?

Bakes

Big as in head diameter, a Martini was designed for the .577/.450, so certainly a .577-type head diameter would fit. Pressure wise the British military thought they were strong enough for a .303, so at least in that head diameter 45-50,000 psi seems OK.

An additional factor to consider, though, is will the prospective cartridge feed down the ramp and into the chamber. Seems like I've heard of one chambered in a .577 2-1/2" case that worked, but a 2-3/4" case wouldn't. Long straight cases are a problem. Maybe a 20/577 Henry?

[ 02-06-2003, 19:39: Message edited by: bpesteve ]

577 2 1/2 inch is as big as you can go,since a 2 3/4 inch won't make the dip into the chamber.

A 577 2 1/2 inch necked to 35 caliber would be interesting........

Brian.

The Martini greener is chambered for 12ga 2 3/4" But the wall thickness is too thin to go that big with a rifle cartridge. The 2 3/4" 577 would fit if a 12ga would fit, but it wouldn't be a swift idea, IMO! The Martini might take the 500NE 3", because of it's smaller diameter, it might make the curve. The rifle was chambered for the 577/450 Martini-Greener which has a case length of 2.34", and a cartridge OAL of 3.12", but the cartridge is a long neck case with a very short full size body so it would make the turn. The straight sided case is where the problem will arize!

[ 02-06-2003, 23:19: Message edited by: MacD37 ]

I have spoken to my gunsmith about making a 50-110 on that action and he said it would not be strong enough, and he would refuse to do the work if I asked him. He said it's a black powder action made prior to 1900 and not designed for high pressure. He suggested not to build anything bigger than the head size of a 303 and keep it low pressure.
All that said he stated that it would take about 10 hours to clean one up to use it for a custom job and suggested that starting with a Ruger No.1 would be a smarter idea.
I had the same thought as you when I saw them advertised for $399AUD

Mac,
I have heard that to do the 577 2 3/4 inch,that you have to mill the groove in the plate deeper so it'll make the dip.

I have always wanted a good modern,single shot 577 2 3/4 inch and plan to have one made one day.A 700 grain bullet at 1800 FPS should get anythings attention on this continent.

416SW,
Your gunsmith is full of horse hockey.Have several friends who have built 50/90s and one even built a 50 Alaskan on the Greener Martini 12 guage shotgun action.They all lived to tell about it.

I really don't think there is a rimmed cartridge out there (short of the 220 Swift and a hot-loaded 45/70),that the large frame Martini won't handle.

Brian.

Weren't the Martini's in 303 converted from other calibers to 303? Wasn't the 303 at that time loaded with black powder? No?

Many Martinis have been re-barreled and chambered for 45-70, 90, 100, and 458RCBS, and I have never heard of any problem with chamberings of this diameter. Another good one would be the 50-100, and the 450 Alaskan Brian mentioned!

There is far less reverse thrust with staight sided cases, than any of the, even lower pressure bottel necked, radicly tapered cases. The big boom problem in the Martini, comes with the LARGE bodied high pressure cartridges. Most failures are in the chamber wall, not caused by reverse thrust, but thin chamber walls. This is somewhat abated by the modern steel of the new barrel, but caution must be practiced when the cartridge gets too large in diameter, combined with excessive pressure!

This action can be had made from modern steel already chambered for 45-70, and others! I think Pedersoli made some of these! Those will take considerably more pressure, but are still not in the class of the Ruger No1. The No1 is a far better choice for this project,IMO!

The Martinis are a weak action, I would go as high as 25-35 Win...even a 45-70 with factory loads, but then someone would shoot a hot 45-70 in it, sure as the world.

Brian M
I was talking to him about loading the 50-110 to 50000psi plus. When I said low pressure I ment in the same range as the 303. To be more precise my gunsmith said you would not want to exceed the bolt thrust of the 303. I hope your friends keep living to tell about it. He may be wrong but I'm not willing to risk it to save $500AUD on an action.

CAS
As far as I know the .303's were all converted from 577/450 as a cost saving. Unsure wether 303 was ever bp but I don't think so.

Bakes
My gunsmith said he has seen/done a few 500 nitro conversions for the Ruger No.1
IMO buy a Ruger an eye or a finger is worth more than a few hundred dollars, it will also have better resale value.

I purchased recently one of these rifles in .577/.450, except mine was an original sporting rifle, and is in good enough condition to be used as a .577/.450 which is what I plan to do with it.

But I also was wondering if the .577/.450 actions would be suitable for some sort of lower powered custom rifles.

Has anyone here ACTUALLY had one made into a .577 2 1/2"? Or has a friend who has? A gunsmith who has done it?

What about the .303 derivatives - such as a .303/.270 or a .303/.25 ? When talking about a .303 are we talking about a full powered .303 round or a loaded down .303? I think a .303 in a Martini Henry would be a neat rifle.

Any information or leads appreciated.

[ 02-10-2003, 07:13: Message edited by: NitroX ]

I only brought it up cause I almost bought a 303 Martini, and the seller couldn't stress enough that it was only for black powder 303 loads. I eventually passed on it for that reason. I didn't want the hassel.

As per Hornady's fourth edition..

"First loaded with 70grs of black powder and a 215gr roumd nose bullet, the 303's charge was replaced in 1892 with a more modern double-base smokeless powder load of cordite...."

CAS
Never realised they loaded it bp. I have a friend that bought a Martini 303 in 1939 and has used it ever since hunting pigs and deer using factory smokeless plus reloads, he is 86 and still hunting - I only wish

Brian I found this thread over there they don't seem to agree either.
http://pub7.ezboard.com/fbritishmilitariaforumsfrm1.showMessage?topicID=315.topic