To carry on where we left off...Smokeless in a Mauser M1871 or 71/84

[Patrick Chadwick]

... produces poor accuracy.


Reason: the fast pressure onset with smokeless bends the action body to one side like a banana, because of the single locking lug, and the "whip" is transferred up the barrel in addition to the longitudinal shock wave that is always generated in every system. When this whip reaches the muzzle, the resulting deviation produces lousy grouping.

Best performance in that long barrel with the single locking lug will be obtained with the slowest rifle black powder you can get - I use Swiss No. 4 i.e 1 1/2 Fg.

This opinion is not just my own experience, but the common conclusion of the BDMP competition shooters who use these rifles. As this is the 3rd time this year that the question came up on the old Jouster boards, I humbly submit it could be included as an FAQ.

Patrick

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[slamfire1]

Words I did not want to read. I have a lot of AA5744, which shoots very well in my Martini Henry in 45/70.

I have been trying to stay away from Black Powder cartridge reloading due to the amount of work I read that is required to make black powder shoot.

At least I have brass, a mold, and a sizing die for my M1871/84.

[Patrick Chadwick]

Sorry if you're disappointed, but I can't alter my judgement to suit what you happen to have in the powder safe. Please note, I did not say you cannot shoot an M71/84 with smokeless powder, just that you will get the best results with coarse-grained BP, as said above. Furthermore, in this country (I do not know where you are), if anything goes wrong you are culpable - for using nitro in a rifle that was not proofed for it. Especially since, in order to get a powder licence, you must have attended an approved course of training, so you cannot plead ignorance. AND all the competitions for this kind of rifle specify black powder anyway (no substitutes!), so what's the point of working up a match-winning smokeless load if you will not be allowed to compete?

The M-H may well do better than the M71 for accuracy with faster powders, as the cross-pin that takes the load is not as severely asymmetrical as the single-lug M71 action. In fact, the extensive trials conducted before the M-H was introduced showed that it was a very rugged rifle. If you have managed to defeat the major problem with the M-H - how to achieve stable combustion characteristics with a charge that just rattles around in in that huge case - then the Mauser case woild be less of a problem in that respect. But still a big problem.

I am not sure that I understand the comment "amount of work I read that is required to make black powder shoot". When I don't feel like reloading, I take my 22 and off-the shelf ammo, but if I shoot my BPCR, I want to get it right.

BPCRs are straightforward. Establish the seating depth required for the bullet you are going to use. Allow for a grease cookie underneath the bullet, with a thickness of anything from 1/10 to 5/16", (you will have to experiment a bit, regardless of which type of powder you use) and a card wad between the grease and the powder. Load powder to the level given by seating depth, grease and card. Fit card wad over powder, add grease. Insert bullet. You can also have a card between grease and bullet (I do). Opinions vary as to how helpful this is. It can be quite thin, as it is only a separator to stop the grease sticking to the back of the bullet.

The load, as a value in grains, is not critical. What does matter is that the the cartridge is full - no air space, but also no heavy compression of the black powder, as this alters it's burn rate, and so varying compression leads to bad ballistic consistency.

But once you have done the experimenting and got a volume measure for the correct charge of BP, it's straightforward. And the rifle makes such a satisfying "boom" instead of that nervous nitro "crack". Yes, it's work, but not black magic, just black fingers!

Patrick

[jon_norstog]

Patrick is right, guys. The only thin I would add is to use a soft lead bullet. 16-to-1 lead-tin is OK, a lot of shooters like 20-1. most commercial cast bullets are "hard" in the 10-1 range and don't usually shoot well with BP.

I've got an 11mm rolling block that shoots great with BP and won't do %$#@ with smokeless. Same for my 45-70.

And man, it smells like Satan's farts.

jn

[Carl R]

So far I've only used Nitro powder in my 71/84s along with dacron filler to take up the void. I would have to agree with Patrick on accuracy. At 50 yards I get about a 3" group which isn't spectacular. I don't notice any crack though because the velocity is pretty low. It's amusing to see the black filaments of dacron floating in the air after taking a shot. I've never worked with black powder mostly because of the horror stories of cleaning bores after using it. I guess I'm just lazy. Given that it's considered an explosive, I don't want to store it in our home, either.

In the USA we aren't saddled with mandatory training classes for shooting or reloading. I hope it stays that way even though it may be riskier. We have more than enough government the way it is.

Here's a link to some detailed photos of the better of my two 71/84s: PictureTrail Gallery

Carl

[jon_norstog]

Hey, Carl,

That is a good-looking rifle. you could shoot BP just fine if you take a thermos full of hot soapy water with you to the range.

Really, that's what those old rifles were meant to use, so why not? Also, it's kind of cool to imagine yourself in the barracks with the old soldiers telling you stories about the '71 war and how they rolled up the French like cheap shag carpet. And the young soldiers are talking tough, how they'd like o fight the Brits .. maybe even the Americans. You're in the barracks, you can smell the leathter greaSE. I get carried away ..

good luck!

jn

[Carl R]

jon, I'll have to consider it. Carl

[Patrick Chadwick]

Carl, you do not have to "take a thermos full of hot soapy water with you to the range". It may be a good idea, but it's often just not practical.

It is not the black powder combustion salts themselves that are directly corrosive, so much as the fact that they are extremely hygroscopic. And when the water gets into the salts, boy, then that is corrosive!

Someone is going to shoot me down for saying this (so what - as an old German saying goes: once you've lost your reputation, you can live as you please) but if you are away for some days and cannot clean it out properly, then a quick fix is to remove the nipple after shooting, while the gun is still hot (they can be vary hard to remove when the gun has cooled down) and then spray a good penetrating oil into the bore and the nipple socket.

That will save your rifle until you can get somewhere to clean it without becoming unpopular. But you must clean it properly before shooting again, as oil-soaked BP residues will clog up the touch-hole/nipple socket quite effectively!

Patrick

[Carl R]

Patrick,

With the 71/84 it would be the bore and not the touch hole and nipple which I assume are muzzle loader features. I know nothing about muzzle loaders! Kroil, "the oil that creeps", is an excellent penetrating oil which I have been using as a bore cleaner. When shooting corrosively primed centerfire ammunition, I swab the bore with Windex window cleaner several times and then use Kroil. I have had no rust in the bores.

Thanks for your comments and help. I just have to get my act together, buy some BP, find load data, and give it whirl.

I have a very nice Martini Henry from the Nepalese horde that I have to get up and running, too. That will be a lot tougher because I'll probably have to cast bullets for it which will be an entirely new experience. I dread to think of what the brass will cost. The 71/84 Mauser brass and bullets were quite reasonable.

Carl

[Patrick Chadwick]

Sorry if I confused you, Carl, I was providing a "broadband" answer for BP rifles in general. Your Windex/Kroil routine sounds OK.

Good luck with the M-H ! They had a reputation for being real shoulder-punchers. Yes, the price of the brass will make you cry - try to think of it as a lifetime investment.

If you are stuck for properly fitting bullets, another quick fix is to buy/cast long bullets for a 451 muzzle-loader (Lee, Lyman and RCBS make moulds) and paper-wrap them. The original bullets were indeed paper-wrapped, so you are being unhistorical if you do this.

If you haven't already done so, I suggest you get onto the Martini-Henry forum, just a couple of clicks away.

Patrick