Just how strong is the Martini action? Does anyone have concrete pressure or other limits handy? What if one were to build a new action to match the original specs, but using modern gun steel? Would there be an improvement, or is the limit somewhere in the design, like the trapdoors? I've heard the Martini is quite strong.

I'm still pondering building a single shot rifle from scratch, and the simplicity of the Martini's design appeals to me. It looks much easier than the falling block in terms of construction. Of course, I know virtually nothing about them or their capabilities. I first saw one up close with these Nepalese imports. I wish I had BAW's problems with too many around.... thanks, maxman

Hello;
I gather these martinis are the last of their kind and have some history behind them. It would be sacriledge to convert the to another caliber and destroy their investment value. The reason they went to the long lever was that there was a problem with cartriges sticking in the hot actions.
Grizz

very true - I'd never buy one of these and convert it. The original 577/450 is plenty potent and has a lot of history! If I had one in as nice a condition as BAW's - I'd love to shoot and hunt it, just as it is. I'm thinking more about building one from scratch as a copy of the original design in better steel. Has anyone ever tried this??

I think a modern steel action would detract from the appeal of the 'old' Martini. Mind some of the sporting conversions that I have seen are pure works of art and a tribute to the gunsmith.
I load some fairly stiff loads in my 17AH (20gn V-max @ 3700fps) and the 222/17Rimmed (25gn HP @3800fps) with only 1/100 cases giving extraction problems. I have original 303 Martini that digests standard 303MkVII ammunition without any extraction problems so I guess they are as strong as the SMLE bolt rifle.
Original rifles in original calibres are really like a Swiss watch; smooth, fast and just magic.

I picked up a .577/.450 Martini Henry about two years ago (among other things)as part of a collection buy out. It looks like it just came off the assembly line. I paid $550 USD for it. Here's the odd thing, it's .458 groove size. As near as my fellow Marti fanatics and myself have been able to figure why is because the rifle is on it's third life - Starting out as a .450 cal infantry rifle in 1872(stamped on the right side) then rebarreled to .303 in 1900(stamped on the left side) and then rebarreled again to .577/.450 MH sometime in the 1920's and sold to private hands, probably to a landowner for antipoacher duty sometime in the 20's(just speculation). The only reason I haven't shot the friggin' thing is the costs 100 bucks for 20 pieces of brass and RCBS wants something like $300 for dies(!) hint: go to CH4D($161 list), and avoid the cheap, noname brass, it is resized shotgun shells - horrible performance and 209 primer size. I'm just gonna have to wait until I come up with the money and then grab brass from Hornerber and dies from CH4D. As for Bertram, well, I keep hearing bad things about their brass, mostly about how soft it is. A buddy uses it in his .577/.450MH Francotte and seems to dent really easily. What's your experiance with it? Also, I have a lead on a 1903 Martini Enfield action that I want to convert to the big rim extractor. I want to chamber it in .577 express, 3 inch. I pretty sure this will fit as I remember somebody doing something with an equally long cartridge, just not that big a bore. Has anybody done this? I'd like to know what the potential problems are before I start cutting metal. I figure with a 23-25" barrel and with a 780 grain cast lead bullet(NEI #396) traveling, at say 1800 FPS, should be a lot of fun. I might even use it loaded up with Triple 7 and shoot the local "old iron" match with it just to see the looks on peoples faces!

Toolmaker

I don't know about their 450/577 brass but I had very poor luck with the box (20) of .303 Savage brass I got from Bertrum. On the first firing I had two necks split. I seemed to be annealed differently from case to case. I cut open a couple of cases and found the wall thickness was very uneven. I am now using 220 swift cases and have no problems.

Toolmaker,
The laerge bertram cases are OK - it's the small stuff that usually has quality problems. Still, I prefer Kynoch brass, as newly made by Kymanco, UK - nice headstamp...
In a pinch, you cn use a cut-down .458 win mag as necksizing die, good if you only shoot your brass in one rifle. In dies, CH4D is probably one of the best buys around - but the stuff is expensive. If just dedicate cases to a rifle, and only necksize - better for the brass... I use a CH4D bushing necksize die for all my BP .45's with a series of bushings according to the neck diameters. 577-450 is a real blast to shoot, although I do prefer 500/450 #2 Musket - that one is easier and more forgiving. But the 'Fat Boy' is pure pleasure, make no mistake - use BP of course!
As to cartridge fit in a Martini - the more pronounced the bottleneck, the better it will work. In straight, 45-90 is about limit. For the really big cartridges, use a Greener GP, it is longer and wider. Better make a mockup to check if the cartridge will 'make the bend'...

Maxman,
I gahter some people made oversize actions for .50 BMG without any problems, using modern steels - the action design is sound, no problems there! But I would go to a Francotte-style action like the Cadet - no holes in the sidewalls, and much easier takedown. Westley Richard made some of these for the ZAR - very nice!

Thanks for the info. It does seem to be a very good design the more I look at it, and I have been reading great things about it as well. Now for the real question: anyone know a source for dimensioned drawings of the action and all its pieces? I'm a bit leery of buying an old rifle and reverse-engineering it, as there is no way to know the true original sizes of each piece. I'd hate to build a new rifle that's filled with already-worn parts!

I'm thinking of something along the lines of a 375 Flanged, or maybe the 45-90 case necked to 9.3mm to make what amounts to a rimmed 9.3x64, or maybe the 9.3x74R, if it's not too long. These ought to work, barring any cartridge length issues. I'll have to wait and see what develops... I certainly don't want to go up to the 50 BMG (ouch) maxman