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I have used turned brass in Martini’s and it is an act of frustration. Anneal will be the first step in every reload. The brass is soft; it is not cartridge brass and should be used with light to moderate loads only. It can and does fail much faster than regular brass. The problem with the Martini isn’t going to be in the rim it’s going to be in the body just above the head and in the Ogee shoulder. Then of course there is the huge neck.

You obviously have had a bad experience with Bertram brass, so I won’t even try to convince you to use it. I do because it good stuff. A few years ago Kynoch and Bertram got together and tooled up for the Martini. A good deal of the Kynoch brass is made by Bertram. Not all. You can contact Kynoch direct for brass. They are on the Martini list in my earlier post.

CBC brass is imported by Magtech; I have been using it mostly for range work. It works just fine. At $16.95 for 25, neck splits are much more acceptable than neck splits in a $5 Kynoch or Bertram case. Neck splits are the biggest problem you will have with the Martini.

Martini bores are standard. The MK I, MK II, MK III and MK IV pattern C have one size the MK IV paterns A and B have another larger size. The Martini Henry rifling has an odd number of lands and grooves, if you can say it has lands and grooves. There comes the problem. Since the rifling is 7 grooves it is difficult to measure. The high points are not opposite. You need a micrometer with a seven sided anvil to measure properly. I have never seen one. You can also use ring gauges. I use a trick taught me by an old Millwright/Gunsmith for measuring odd sided objects. It’s simple. Roll you slug between the slack jaws of your caliper. Do this several times and you will see the repeat reading. The MK I, MK II, MKIII and MK IV pattern C should be .464 and the MK IV will be .468.

Some thing else to keep in mind when you slug the Martini bore, the bore is tapered from the chamber forward. The nominal bore is .450. A .449 plug gauge will run the full length; a .451 plug gauge will be rejected full length. A .451 plug gauge will run four inches from the breech; a .450 plug gauge will run eight inches. The remainder of the 24 or so inches of barrel will be cylinder.450 The grooves in the tapered section are .009 deep, .007 in the cylinder section. .450 + .007 + .007= .464. The twist is 1 in 22 and the rifles like the 480 grain bullet.

I have often wonder about what happens to a bullet that obturates in the Martini bore. It gets slugged up on firing and squeezed back down as it goes out the bore. Seems like a lot of distortion is possible.

I have seen the measurements credited in Cartridges of the World of .452 to .455 for bullet diameter. Some have said that measurement comes from the slug with the paper removed. I don’t know if that is true or not.

I do know the List of Changes that the British military use to set out official measurements says the paper patched grooved bullet used in the Coil Case has a major diameter .449 with out the paper. The paper patch makes up the difference. The LoC gives the dimensions of the Paper patch but not the thickness of the paper. If you scroll down on the Martini list that I posted you will find under Research Sites a link to a site called AN ILLUSTRATED TREATISE ON BRITISH SMALL ARMS AMMUNITION. Some useful information there. A good starting point is how they made the original stuff. The LoC bullet is 12 to 1 alloy.

Compression. The Martini has a very large powder chamber with a smaller neck. This no US style BN cartridge. When you compress you are compressing straight down and not outward. Plus in order to compress you have to put far more powder in the case than is needed. The LoC load is 85 grains. 85 grs. does not come to the bottom of the shoulder in a CBC case and just barely to the shoulder in a solid head case. By the way the LoC load is a good starting point, but is by no means the end-all.

There two reasons to stay away from the heavier loads in the Martini. Recoil-felt and recoil-control. The action is perfectly safe with heavy loads. The buttstock tends to bite from length of pull and shape. Not a big deal if you are conditioned to it. But control is another thing. Because of the shape of the action, in heavy recoil the rifle will jump out of your hands. The British practice was to place the thumb on the thumb rest on the back of the action. This supposedly cures the problem of the thumb bashing your nose when the rifle recoils. For me this is even more awkward. I just wrap my thumb over like normal. I seem to have more control. I have not got a bloody nose yet…knock on wood.

I look for 1250 fps across the chronograph with the black powder and get that with the Swiss 1F. I have been working with smokeless loads and looking for 1300 fps. I did test some .480 gr bullets at 2200 fps. The only problem was catching the rifle as it jumped out my hand at each shot.

I have used your website many times over the years. I find it very useful. Thanks!!! The more I read “Coydog's” stuff the more frightened I become. I take his recommendations with a large grain of salt.

Bottom line for the 577/450 in a Martini Henry rifle start with the LoC load and work out from there.

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DD, Ret.