Oklahoma Hunting Forum banner
21 - 40 of 68 Posts

·
Premium Member
Joined
·
359 Posts
Discussion Starter · #21 ·
Had a bit of memory refresher. Open the reamer drawer of my tool box and saw two more cartridges. Before I went to Afghanistan in 2013 I sent these two round off to JGS Reamers and had a reamer made.

As I looked at the cartridges they seemed a bit long to me. The reamer is Marked .577 3" NE. Here is one of the cartridges up against a ruler.

Wood Office ruler Font Ruler Material property


I think I had checked and found that the 3" version of this cartridge would fit this action and intended to rechamber.

Because of the rotational breech block of the Martini length and diameter of the cartridge is critical. Some long cartridges will not slide down the breech block into the chamber. Geometry is critical. Long cartridges will not "turn the corner" and go in.

But, this one does.

Tire Automotive tire Automotive lighting Liquid Rim


As pictured this 3" cartridge won't go all the way in the 2-3/4" chamber. Reamed out it should fit.

But should I?

Right now the gun functions with 2-3/4" shells. Extraction is weak on the Martini design and crisp extraction is required for ejection to work. The load position of the breech block is critical in the Martini. Position now is fine. For the 3 inch shell it would need adjustment.

The other problem is, will this reamer clear the current neck out when the chamber is lengthened. There could be sstep if the current chamber has an over sized neck.

No I think for now I am going to leave this alone. No need to create issues that don't exist.

Product Writing implement Office supplies Material property Cone


.303 British, 577 2-3/4" NE.

Douglas
 

·
Super Moderator
Joined
·
12,622 Posts
My shoulder hurts just looking at that round.
 

·
Registered
Joined
·
1,045 Posts
Is there a pressure difference between the 2-3/4 and 3" cartridges?

Playing with old steel and increased pressure wouldn't give me that 'oh so comfy' feeling, but if there is a ~ 1K PSI or CUP difference, I don't think its going to hurt anything.

However I'll finish this by stating that I have zero experience with that rifle or cartridge.
 

·
Premium Member
Joined
·
359 Posts
Discussion Starter · #24 ·
Pressure is an important consideration and often mis understood particularly in these larger British cartridges.

The action was made in 1925 and in steel that is consider to be a modern steel. The barrel is also modern steel. This a not an old antique gun. This gun has a barrel the weight of a rifle barrel and not the thin barrel of a double rifle. I have the utmost confidence my rifle is safe.

The 577 NE's were made primarily for double rifles and thus pressures are low. The pressure standards of the original cartridges are recorded in tons per square inch. Cordite loads for both the 650 grain bullet and 750 grain bullet in the 2-3/4" chambering have a working pressure of 12.5 Tons. Both of these bullets used 90 grains of cordite.

The 3 inch version used 100 grains of cordite for the 750 gr. bullet and 90 grains of cordite for the 650 gr, bullet These of course were loads consider safe in double rifles. The 750 grain load is rated at 15 Tons, the 650 gr at 10 tons.

For loading I will be working with the Woodleigh Reloading manual, load data from Barnes Bullet's and Greame Wright's book Loading for the British Double Rifle.

Wright's book is an extensive work on loading the old big British cartridges with modern components to be be safely shoot in old antique rifle. His work in is done in cooperation with and by extensive testing in the Birmingham Proof house. He also collaborates with Kynamco the modern Kynoch company.

Wrights methodology is to pressure test original cartridges. Then using modern smokeless powder develop loads that produce the same pressures as the original. Greame work has determined that pressure is the critical factor in making double rifles regulate-that is to get both barrels to shoot to the same point of aim. Not a big issue for me shooting a single shot, beyond find a safe load.

I will be scrupulously following Wrights works as I know his loads has been pressure test and will be safe to fire.

If you can shoot 12 gauge slugs, this one should be a pussy cat. Well the practice rounds will be anyway. :)

I'm not kidding my self recoil will be robust.
 

·
Super Moderator
Joined
·
12,622 Posts
Sounds like you have the load data and writings of someone who certainly did his due diligence in writing that book/manual.
 
  • Like
Reactions: diggler1833

·
Registered
Joined
·
1,045 Posts
Sounds like you have the load data and writings of someone who certainly did his due diligence in writing that book/manual.
Yeah, one needs reference material for this kind if stuff.

My F-I-L has a S&W 66-2. He was showing it to me one day. He showed me the "hot" handloads his buddy made fir him using (18!) grains of Alliant 2400 under a 158gr SJHP. That one opened my eyes a bit as I knew it was wayyyy over max without looking it up. I pulled up the info, which shows a max of 14.8gr. Just because the powder will fit doesn't mean you can load it. I explained to him what a proof load was, and then detailed how he was essentially proofing his gun everytime he shot it.

Anyway, he loaded the revolver back with those overloaded rounds and put it up...F me I guess. I went back behind him and swapped some of my mag loads in his gun. I checked it some time later and saw that he had reloaded the gun with his damn handloads again, so I swapped my stuff in once more and then chucked his 'exploders' in the woods below the house.

Forgot I had done that until we did a controlled burn about two years later. Handful of booms :D. F-I-L was stating about how "those sandstone rocks can really let out a pop when they get hot enough." :LOL:
 

·
Registered
Joined
·
35 Posts
If it were mine, I would leave it alone. As you said, geometry is crucial and, 'if it ain't broke, don't fix it!' If you have a 100% reliable rifle at this point, I would count my blessings. Just my 2 cents.
BTW - On my one trip to Africa, I wound up putting four shots into every animal. Not necessarily because they needed it but, with dangerous game, there is always an 'insurance shot.' I'm sure my Cape Buffalo was dead after the second shot. However, the way we had to approach him, he was laying with his back toward us after that second shot. He didn't seem to be moving, but the PH told me to put one between his shoulder blades. I did, and he didn't move. Still, we maneuvered around to approach him from directly behind. PH approached very cautiously and nudged him in the butt. Again, he didn't move, but the PH still had me put one more right behind his shoulder. There were lots of villagers nearby, and they had a villager get killed in a previous year when they approached a "dead" buffalo that wasn't quite dead.
Anyway, I'm enjoying your reports of working up all the details with this rifle prior to your trip. And, I really look forward to the post-trip reports!
 

·
Registered
Joined
·
1,045 Posts
If it were mine, I would leave it alone. As you said, geometry is crucial and, 'if it ain't broke, don't fix it!' If you have a 100% reliable rifle at this point, I would count my blessings. Just my 2 cents.
BTW - On my one trip to Africa, I wound up putting four shots into every animal. Not necessarily because they needed it but, with dangerous game, there is always an 'insurance shot.' I'm sure my Cape Buffalo was dead after the second shot. However, the way we had to approach him, he was laying with his back toward us after that second shot. He didn't seem to be moving, but the PH told me to put one between his shoulder blades. I did, and he didn't move. Still, we maneuvered around to approach him from directly behind. PH approached very cautiously and nudged him in the butt. Again, he didn't move, but the PH still had me put one more right behind his shoulder. There were lots of villagers nearby, and they had a villager get killed in a previous year when they approached a "dead" buffalo that wasn't quite dead.
Anyway, I'm enjoying your reports of working up all the details with this rifle prior to your trip. And, I really look forward to the post-trip reports!
No harm in an assurance shot. If a hog is laying upright, they always get a second shot from me. I'd bet 80% of the time they are still laying upright that they aren't dead until they get that assurance shot.
 

·
Premium Member
Joined
·
359 Posts
Discussion Starter · #29 ·
I will be most willing to shoot additional rounds into a Cape buffalo as directed by the PH.

I have 14 months before this hunt. So if there are problems I need find them now and take care of them.

Well, that being said, a feature of the Martini has showed up as a early problem. When the breech is open the blocks sits up just slightly above the bottom of the chamber. The lever can be pulled down against the spring tension, pulling the block down to clear the chamber. This feature allows for the action to be carried with lever down and a round in the chamber. The breech block catching the edge of the cartridge holding it in the chamber.

Here's what that looks like.

Bumper Wood Tool Auto part Cable


The problem is that the breech block is sitting to high. When loading the gun the the front of the breech block is forced down by the cartridge going into the chamber. With the block sitting this high, you can't get enough leverage with the cartridge to force the breech block down.

It is a simple fix. This is called loading position and its height can be adjusted. Internally when the action is open the sear arm of the tumbler is blocked by web between the horns of the lever, Here is picture of the lever.

The two upright projections are the horn, The flat spot at the bottom between the horns is the web. This web can be cut down and and it will lower the breech block.

Wood Household hardware Metal Fashion accessory Rectangle


I can do this. Most Martini actions are fairly easy to assemble and disassemble. The Greener actions are notoriously more difficult to work with. They will make you cuss. The adjustment is easy, the reassembly to test is not. Grrrr.
 

·
Super Moderator
Joined
·
12,622 Posts
Good luck with that. I hope you get the problem fixed and everything stays safe with it.
 

·
Premium Member
Joined
·
359 Posts
Discussion Starter · #33 · (Edited)
In two weeks I am going to have carpal tunnel and cubital tunnel surgery, so I have two weeks to get this stock cut to fit and test loads shot.

I want to get this stock roughed out and some test load made up with Trail Boss. I want to test shoot this gun to see if there are any problems other than load position. Then I will send the gun to John Taylor for adjustment.

Today I worked on the forestock.

Before.



Pointy ugly.



20 minutes with the patternmakers rasp.




Much better.



I am going to install the butt pad tomorrow.

I found a partial can of Trail Boss powder. This will work for these test loads. But i will need more for the practice loads. I have 650 grain .585 CBE mould for bullets. I think I have some bullets already cast in a drawer. I should go look.

Still looking for some more Trail Boss.
 

·
Administrator
Joined
·
15,152 Posts
Coming together nicely!
 

·
Super Moderator
Joined
·
12,622 Posts
Can’t wait to see the finished product.
 

·
Premium Member
Joined
·
359 Posts
Discussion Starter · #37 ·
Thanks guys. The finished product is months down the road.

I will be loading up some 650 grain cast bullets later today and then go out to range this week and do some function testing of the gun. I already know the loading position of the breech block needs adjusted. Test firing will tell me if striker height needs adjusted also, or if there are other issues.

After that, i will send the gun off to John Taylor in Idaho and he will do the adjustments. He is backed up several months. That is okay because of the hand surgery I am having I won't be able work with the gun any way for a couple months.
 

·
Premium Member
Joined
·
359 Posts
Discussion Starter · #40 · (Edited)
Well I didn't get any reloading done yesterday, but I did plant a bunch flowers for the wife after church.

I rounded up some cases to reload. Most of my cases are 3 inch length right now. I need to trim them down to 2-2/3". I do have some dummy rounds made in 2-3/4.. I pulled bullets from them. I also found a couple of primed cases. I don't know what they were prime with or when, but they worked good to test the striker impact.

Wood Household hardware Metal Circle Lock


Striker impact is well centered. That is good. Striker impact is adjustable in a Martini, lowering the point is easy. Low impact point is also a common fault. Raising the impact point is can be done. Old school is to heat the horns of the lever and draw them out. Modern guys weld on top of the horns and cut them down to change impact point.


This gun or rather the action is a Greener Police Gun Mk III. It started life as a full stock shotgun.

Wood Metal Font Cuisine Cable


It was made in the mid 1920's. Without looking it up it most likely started as 12/14 shotgun. Some of the very first guns were standard 12. Most were12/14. The striker had two side prongs and a firing pin in the middle. The shells had a ring in the base that the prongs went in, to allow the firing pin to hit the primer. Regular shells have no ring and the side prongs of the striker stopped the firing pin from hitting the primer if a regular shell was used. This was so if the gun was stolen the bad guys could not us regular shotgun shells in it.

The chamber was modified for 12/14 shotgun shell. The shell was basically a bottle neck, back part standard 12 gauge, 14 gauge in the front. A 12 gauge shell would not go in the chamber. I have seen these shells in brass and hard plastic. Never seen them in paper or soft plastic.

The early guns like this had what is called a solid action. Later they had the action split below the receiver ring to facilitate take down for cleaning. Only solid actions are considered strong enough for centerfire rifle cartridges.

This action is different, larger than the British Military 577/450 Martini Henry. Those two guns are as alike as Winchester Lever action and a Marlin lever action.

I acquired this gun years ago from a friend as some one else's unfinished project gun. It has sat around in my gunsafe for probably 20 years or so. I got it for a retirement project. I retired 14 years ago.

Hopefully a year from now I will be packing my bag getting ready to head to SA and make this gun earn its keep. Standby for pictures...
 
21 - 40 of 68 Posts
Top