paper patching a Gahendra

[Beekeeper]

All right I will say at the beginning I know absolutely nothing about paper patching!
But I will learn even if it kills me.
I bought a Gahendra Martini-Henry from IMA and have got it partially cleaned up.
It originally shot paper patched with black powder and That is the way I intend to shoot it
I have slugged the bore and altho I'm not happy with it ,it reads 451 at breech and muzzle but 455 in the middle of the barrel.
I have a lyman 446110 mould for the 43 Mauser that I own and was considering using it for the boolit
using .oo15 paper I will come up with a .452 boolit.
With pure lead it may cast a little larger but not much.

My question is am I on the right track or do I need to look elsewhere.
If on the wrong track please point me in the right direction as far as mould and paper

Thanks in advance.


beekeeper

[303Guy]

That would be a 577/450 Martini-Henry made in India? Is there any possibility of an error in the middle of the barrel measurement? (Although I'm sure you would have checked and rechecked!)

[Beekeeper]

No mistake in the measurements.
It is the Martini - Henry made in Nepal
No bulging on outside of barrel and very little if any pitting inside..
The bore is actually pristine for something this old.
These things were each hand made in plants similar to the Khyber rifle works.
I am going to do a chamber cast today to confirm some of my data.
All of the ones people have slugged so far and reported on various websites red in the .460 range. Have a PM in to buckshot now and hope he can give me a little insight on what to do.

beekeeper

[Red River Rick]

I have slugged the bore and altho I'm not happy with it ,it reads 451 at breech and muzzle but 455 in the middle of the barrel.
beekeeper

Could you please explain how you were able to measure the slug at 0.455" even after it passed thru either the muzzle end or the breech end, both of which measure smaller than the number provided? Doesn't make sense, unless you have some sort of alloy that springs back.

RRR

[pdawg_shooter]

Could you please explain how you were able to measure the slug at 0.455" even after it passed thru either the muzzle end or the breech end, both of which measure smaller than the number provided? Doesn't make sense, unless you have some sort of alloy that springs back.

+1 ON THAT!

[montana_charlie]

Been wondering the same thing, myself...

The only cure for that (if it exists) would be to put a reverse 'choke' in the rear half of the barrel. Then, the bullet would enter an 'enlarged' breech end (say .456")...squeeze down to .455" at the middle...and continue to choke down in the existing bore as it proceeds toward the muzzle.

Doesn't sound easy...

CM

[Red River Rick]

I could see the bore having some "taper" in it, with the breech end being larger. But this "JUG" bore has me wondering.

The original "Henry" system of rifling was a 7 groove, right hand twist, 1 - 22". Groove diameter is 0.469" and bore is 0.450". And designed for use with a 480 gr Paper Patch bullet.

Some of those "Made In India" copies are very nicely done, especially for being hand made. But as far a shooting them, I'd be skeptable. Approach with caution, if you intend on shooting it, it may be wise to use BP only.

RRR

[Beekeeper]

I grew up in a machine shop and still have some of my tools.
one of which is a distance reading ball mike that you can put an 18 inch extension on.
They never sold well as not too many people wanted to measure hole dia. in the middle.
But as an 17 year old I had to have all of the new toys( no different from teenagers today)nand bought one. Think I have used it 2 or 3 times in my life.


beekeeper

[Red River Rick]

Beekeeper:


Well, that'll do it. And as you mention, not a common, direct reading instument. I too, have spent a good portion of my life in a Machine Shop as well. I've seen them (bore micometers), but never used one. Would be nice to have.


Originaly, you said..............


I have slugged the bore and altho I'm not happy with


So, based on that information, I could not see how you came up with the middle bore diameter.

The barrel was hand made, hand lapped and hand rifled. So, based on that, it doesn't suprise me that the midddle of the bore is larger.


RRR

[303Guy]

So the question is, does it matter? As long as there is sufficient pressure in the middle of the bore, the boolit should obturate to seal the bore. Otherwise a thick felt wad under the boolit? Someone used to make turned brass cases with a straight bore. (It could easily have a seating step). I know folks would sometimes have ten cases or so and use a simple reloading tool on the range. No sizing is done and it's a single shot. The straight bore reduces the case volume to allow the use of suitable smokeless powders.

[Red River Rick]

So the question is, does it matter? As long as there is sufficient pressure in the middle of the bore, the boolit should obturate to seal the bore..........

Probably not. The bullet should obturate, as you say, at the middle of the bore, and then swage itself down when leaving the muzzle. The pending results (accuracy) would be interesting.

RRR

[303Guy]

Beekeeper, I am real keen to hear the final outcome. I hope you get round to firing it soon! Will you be making your own brass?

[Digital Dan]

I rather doubt a bullet will obturate at mid bore. More important to determination of potential, what are the dims at the muzzle? I don't see a bright future for the barrel, based on what's been described.

[Beekeeper]

Midway sells bertram brass and lee sells dies for it.
If I can get it to clean up further I intend to shoot it with a lanyard at least once .
Do you think I can use the .446 boolits or would you think 45/70 boolits would be better.
Have never fired black powder or patched boolits before so if the bore will clean up to where I think it is safe it will be a complete new learning experience for me.
If the bore will not clean up to where I think it is safe I am going to look into a barrel liner in either 30/30 or 45/70.
Either way the old girl will once more belch smoke.


beekeeper

[303Guy]

Shooting PP boolits will in itself clean the bore. Polish it actually. You don't need sizer dies if you patch. Not to say you shouldn't neck size, just that you don't need to go to that expense until you know the rifle will shoot as is. I know of someone who used to seat his cast boolits with loo paper as a cup to hold the boolit in place. I took his idea and started loading my hornet using paper hand towel strips. It worked real well for me in my hornet, good for magazine use.

[Bent Ramrod]

Here's how I would proceed:

Cast a few of the .43 Mauser boolits fairly soft and patch them with two wraps of paper. The resultant slug should be just big enough to push through the bore with a stout cleaning rod. Change paper thicknesses until this happens.

I would guess that the boolit thus patched should be a sliding fit in the brass, once it is sized to fit the chamber. (I have a Peabody in .43 Rem Spanish that does not chamber a groove diameter boolit loaded into the case.) The less you have to run your brass through the sizing dies (especially as it is Bertram) the better, anyway. Charge the case with black powder. Put a wad or two over the powder, a grease wad over those, and another wad over that, and put the patched boolit in the case neck so it is sticking out into the rifling. Make up the space with more wads, if necessary.

Fire these cartridges and see what they do on the target. You may get away with blow tubing, or may have to clean between shots for best results. Then you can start messing around with powder charge weights, compression and all the other stuff that drives the BPCR addict crazy.

You may ultimately need a heavier boolit, but see what you can do with what you have. A large caliber BP bore can be surprisingly crummy and still deliver decent practical accuracy. I have a High Wall in .45-70 with a speckly bore and a chip out of the rifling that still goes 2"-3" with notch-and-bead sight at 100 yards with the 457124 boolit, though I haven't tried patched slugs in it yet. I would advise against rebarreling your rifle. So it couldn't have been used in the Nepalese National Matches; it's still a piece of history, yes?;)

Ask Martinibelgian or Bad Ass Wallace to supply some advice on this endeavor. They are the .577-450 Martini experts.

[Beekeeper]

Thanks for the advice everyone. I appreciate.
Am still working on the barrel, have had it on an electronic bore cleaner constantly for 2 days and am still getting Yakmoline out of it.
Honestly I thought I had it clean, getting old I guess.If it keeps up the way it's going I may have a good barrel after all.
Will give everyones advice a shot and see what happens


beekeeper

[montana_charlie]

If it keeps up the way it's going I may have a good barrel after all.
If it keeps up that way, you better re-check the diameter after you get all of the Yakmoline out...

CM

[Gunfreak25]

First of all to those who said these were made in India, they weren't. The Gahendra is a Nepalese design, and was ONLY made in Nepal, the British never adopted the Gahendra system either. The Gahendra is a much different design than the Martini Henry is, in fact internally they have little in common. The Gahendra was taken from the Westley Richards and Peabody design, and then "improved" if you will. These majority of these that people have been getting from IMA, do show much better overall workmanship and tollerance than Khyber Pass rifles, in fact it's not even fair to compare them to Khyber guns. However being that these were still "handmade", the parts are no where near the tollerance of what British manufactured weapons at the time were made with.
As many know, the bores on these vary greatly. I've seen some slug as tight as .447, and some as large as .460. But the majority of them that I have seen, have been slugging to .456 to .459, mine slugs to .457. The Gahendra design is not as strong as the regular Martini is, plus with the questionable mettalurgy of the steel and techniques used to make the barrels, it makes you want to think twice about shooting them. So far i've seen some barrels that have the "swirl" marks on them, which lead me to believe they were made like Damascus shotgun barrels, which were made of steel rods twisted and welded together to form a round bar. If done right it is actually quite a strong design, on the other hand some Gahendra's, including mine, appear to have been made from solid round bar. Which was a preffered method of gun making at the time. So have the above being said, many people do shoot theirs, and do it quite safely with no ill effects. If they are in good mechanical shape I see no reason why they should be left as wallhangers, just don't make them a regular shooter, I plan to make some carbine loads for mine, using the proper diameter bullet of course. I hear these Gahendra's can be very accurate when fed the right diet.

[303Guy]

If for some reason, this rifle won't shoot well with PP due to the bore, would fire-lapping it improve it? That process should theoretically tend to give a bore a taper toward the muzzle and if the breach end is tighter, then the chances are, fire-lapping might open up the breach end a little without affecting the looser middle section. Just a thought.[smilie=1:

[Gunfreak25]

The bores on all of the Gahendras I have seen already have a taper to the bore.
:-D

[303Guy]

Is there a way to 'expand' the patched boolit as it passes down the bore, Minniball style? Expansion should cease by about mid-bore I should think? (Or hope, I should say). But that could be controllable by powder charge adjustment).