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Bigjohn
05-13-2006, 04:13 AM
This one will possibly bring out the darkside in some of us[smilie=1: but it is one subject I have not seen discussed here. Sometime ago I read an article by a writer whose name has escaped me, mention that (possibly in his opinion):coffee: accuracy from a bottleneck cartridge was in some way hindered.
Now, as I read a lot of different articles and books from UK, USA and Ozzie writers I believe he was refering to Cartridges of the Black Powder era rather than the modern type. (If correct this may have same effect upon smokeless powder shooters, so all are welcome to place their thoughts here).

Having read most of what Paul Matthews and others have written about BPCR; the only possible way which I could see that shoulders on a bottle neck case would effect accuracy is if the shoulders create some sort of trubulence with the powder and gases trying to rush into a constricted opening.

The theory as I understand it is:-Upon ignition the projectile and the rapidly burning powder commence to move up the barrel. This is in effect a projectile which is rapidly losing weight. If you are shooting a straight tapered case, then it is simply an easy run towards the muzzle but in a bottle necked case there is the bottle neck to negotiate which may require the consumption of more powder to overcome.

Unfortunately, due to poor fiscal planning, my inability to win the lottery and outright lack of wealthy nearly deceased cousins or family I do not have the equipment to run side by side testing. (But if someone could see their way clear to the appropiate loan for research purposes:kidding: I would gratefully undertake the required research and post it here first).

As I said at the start; this may bring out the experimenter in all of us, hence all opinions are welcome and will be considered.

martinibelgian
05-13-2006, 10:57 AM
or in more direct terms, 'hogwash'. However, it is true that BN cases and BP listen to a different set of rules to get them to shoot.
Here's another theory:
Because of the constriction, you can get more pressure with less (and slower) powder in a case of the same capacity, which will give you a more efficient powder burn, hence better MV (I also just address what you are addressing with your theory - MV, not accuracy)
Also sounds plausible, no?
And why would it be different with nitro powders - which are most BN's...
Also, at the end of the B¨P era most countries were using BN rounds - not straight-walled cases (the US being the exception), so there must have been a good reason for it.
Mind you, lots of compression will give you not-too-good accuracy in BN cases, but they can be made to work indeed, using a different set of rules. As soon as I have my 500/450 #2 Musket match rifle up and running, we'll talk again...

Greetings from Belgium,
G.

Bigjohn
05-13-2006, 05:29 PM
Welcome aboard martinibelgian,

As I recall (from some of the dim dark regions of my mind) there was an article which retold of a test conducted late 1800's early 1900's which used three rifles. One, a Trapdoor Springfield 45/70/500 Govt.; two, a Martini 577/450/85/480 and the third (I cannot recall as my interest lay with the Springfield and Martini). The shots were fired over a distance which exceeded the sight settings on the military sights (Approx. 2.5 miles). The Springfield came out the winner with the greater number of hits. This was achieved with 15 grs less of powder in the case.

I acknowledge that most Military adopted the BN case form for their service rifles including the Martini Henry. One snippet of information on the Martini is the original case was a straight case containing the same charge and projectile combination as the bottle neck case, the BN case is referred to as the "Short Chamber Martini". It is referred to as such in B. A. TEMPLE's book on the Boxer Cartridge in Military Service.

The military has different requirements to the sporting or target shooter and it should be noted that Sharps chambered a great number of their rifles for BN as well as ST cases. In the target world it appears that mainly the ST cases have survived and continue to excell today. Notwithstanding all that I have said, it may only need a little experimentation to have the BN case reappear on the shooting scene. I am not intending to knock the BN case (I shoot some myself but not in BP yet) rather I would like to confirm the performance figures in comparison to ST cases of a simular capacity.

I believe the military adopted the BN case for the Short Chamber advantage, eg speed of reloading under fire. Most of the information I quote is still stored within my library but it would take years of re-reading to locate it. Memories of what I have read is what I am checking out on this forum and any opinions are welcome and will be considered. I will do some research in my library and see what Mr Temple says on the difference between the short and long case Martini 450.

I hope you enjoy your time with us on the forum and learn as well as contribute further.

John

Bigjohn
05-13-2006, 05:53 PM
As a footnote to the above entry; Library-primary rack #1, shelf number 2 fourth from left (The Boxer Cartridge in the British Service/B. A. Temple)
Page 66 "Cartridge, Small Arm Ball, Boxer Henry,0.45-inch, Martini Henry Rifle, Long Chamber (Mark A); Intro 1869. Overall length 3.750; case 3.220; projectile 480grs Paper patched; charge Black powder R.M.H. or C&H #6 wt. 85 grs.

Page 69 "Cartridge, Small Arm Ball, Boxer Henry,0.45-inch, Martini Henry Rifle, Short Chamber (Mark 1, 1st Pattern); Intro 1870. Overall length 3.150; case 2.320; projectile 480grs Paper patched; charge Black powder C&H #6 wt. 85 grs.

Unfortunately no MV's were listed or offered.

Buckshot
05-14-2006, 03:38 AM
..........Big John, you're refering the trials conducted at Sandyhook, NJ of 1879 I think it was. I have the old article from a 'Rifle' magazine. Before, or just as David Minshall was setting up his LRML e-list we got permission from Wolff publishing for him to include it on his website.

..............BTW, Martinibelgian, welcom to the board, and nice to see you here. I post on the British Militaria board as Whitworth (or Whitworth92374 depending upon how E-Z board is acting :-).

As it was in the test the std army issue 45-70-405 petered out after a decent showing, and the winner was the 18" twist Trapdoor 45-85-500. These results lead the ordnance folks to go with the 500 gr slug. HA! Guess they called up Ideal and ordered a bunch of 457125 moulds :-).

So far as the 577-450 went, I don't think the British were ever really satisfied with it's overall accuracy. No one ever said they felt it was underpowered though!

I don't know from personal experimentation because I have only 2 BN cartridges of the BPC era to use, and have never been enamoured of the after action case cleaning chores. Smokless being so much easier to deal with in that regard, and in loading. One is the 577-450, and the other is the .43 Spanish which is a facsimile of the Remington 44-77.

I do have to add the recent use of the 577 Snider, although not really being necked as we think of it. Then there is the 11.5x42R Comblain. The later never having been used by me with BP. However it DOES have a neck, after a fashion. A bit more definative then say a 44-40, but there none the less. What I have read in passing is that necked cases using BP produce a greater amount of fouling in the barrel ahead of the casemouth.

In shooting BP in a muzzle loader there is fouling the length of the barrel, yet the concentration becomes heavier the closer we get to the breech. Even in my Whitworth or Rigby with thier comparatively high pressures, using the excellent Swiss powder, you will eventually get a fouling ring deposited in the area of the top of the powder column and the wad. That is unless you wipe to the breechface after each shot.

If in fact it is true with BN cases that the fouling is heavier at the casemouth then it is with straight cases, it follows that for some reason the addition of the BN constriction is the culprit. It is a fact that the Sharps Rifle company moved away from BN cases early on and did not encourage customers to spec rifles chambered for them. I believe they also sited increased fouling.

..................Buckshot

Bigjohn
05-14-2006, 08:53 AM
Buckshot, that sounds fairly close to my recollection of what I read. It is possible that Paul Matthews made mention of the test in one of his books to illustrate a point but I can not recall which one. In reference to the first comment I made in my first post re the alleged effect on accuracy, most writers express an opinion in their articles; sometimes they are right, sometimes not.

I have and shoot several single shot rifles, most of them are in the 45/70 chamber. I do have a Martini Henry Carbine 577/450 which I have yet to fire. Recently acquired a set of LEE dies for this calibre. I have the molds for the projectiles, lubed or Paper patched type. Hope to have it going soon.

Today, I fired my Martini Enfield Mk1 .303 converted to 45/70 with 65grs ffg and 500 gr LEE projectile. Due to the over all length of the cartridge I had to manipulate the lever to allow the cartridge to fully enter the chamber. This I believe is one reason why the British adopted the Short Chamber version of the cartrdge.

As you mention in your post there may be valid reasons why Sharps for example attempted to steer their customers away from BN cases. Otherwise there is no reason which I can see that if all other requirements for an accurate rifle are meet, for BN cases to fall short in the accuracy stakes.

Here in OZ we can find it difficult to obtain some of the other calibres suitable for single shot rifles. But we are a resourceful lot down here, give us a chance and we could just about do it. Take Bertram Brass for example. It would be interesting to do a side by side comparison say with a long chamber Martini and a Short Chamber Martini. Powder and charge, projectile and all other procedures to be closely followed?

John:coffee:

martinibelgian
05-14-2006, 10:16 AM
Buckshot is right - the round that won the Sandy Hook trials was NOT the issue 45-70, but rather what we would call the 45-90 - same powder charge as the 577-450 (85grs), but heavier bullet and faster twist - and at long range, bullet weight will prevail... You have to read the report carefully to find this, as it is somewhat hidden between the lines (national pride, I presume). Also, don't forget that these were match rifles - not standard military issue stuff. The 45-70-405 was actually the 1st round/rifle to drop out, and one of the reasons to adopt the 500gr slug afterwards by the US.
And don't forget to look outside the US when looking for target cartridges - rounds like #2 Musket, 461 gibbs etc. were quite popular and very accurate. Also, I believe that the 1,000 yds Creedmoor highest score was held for quite a long time by the .40-90 What Cheer (yes, another BN case) in the US, untill dethroned by the smokeless gang.
And the fouling issue - I don't buy it. Just today I shot 18 rounds of 577-450 with blowtubing, just like my 45-70, and I didn't have any more fouling, no crud ring. It just is, as I already stated, that these rounds need another reloading logic: Horse down on the powder column, and you will get Large ES spreads, lots of fouling and whatever. Same when you use too fast a powder. OTOH, use no compression or very little, and things start working. I have never experienced that infamous crud ring when respecting these rules, and I do shoot quite a few BN rounds (mainly 577-450 and #2 Musket, and soon 8mm Guedes).
Hearsay and urban myths usually go hand in hand. 1st hand experience is another thing entirely...
Mind you, an abrupt shoulder (like 577-450) is not that good an idea with a BP round - a gentle, sloping shoulder is much better. And for case cleaning? if you use an ultrasonic cleaner, no problem at all...
Also, rounds like 40-90 straight etc were also known for fouling issues - one of the culprits cited being excessive case (powder column) length. But some BN's like 40-50 Sharps BN are reported to be very easy rounds to shoot, and to work up accurate loads. Just don't make the mistake to compare a modern match rifle with perfect bore to a well-used military rifle with a well-worn bore...
Also, the modern use of almost exclusively straight cases is a typical US phenomenon - that and the availability/price of 45-70 of course... Still 40-65 (yes, necked 45-70 - or should that be tapered?) is working quite well in silhouette, so??
FWIW, the long-chamber martini round afterwards went on to become the 45-3 1/4" express - an excellent hunting round, but also known as a barrel fouler...
The rules for BN's are :
1. use a slower, coarser powder than in a straight case with similar capacity (like Fg instead of FFG)
2. None or very little compression
3. No neck tension, and bullet seated into the lands (rather difficult with a standard issue MH, I agree - but they weren't made as precision rifles)

Trying to use a straight-case logic with BN cases will get you fouling and other problems - but that is not the fault of the case shape itself.

Getting of my rocking horse now...:)

kodiak1
05-14-2006, 09:35 PM
Jeez Guys keep writing I am taking notes. I shoot a 4-90 SBN mostly smokeless but am starting to play more with the Black Powder. It seemed to shoot fairly accurate with both but I can see a few steps that I am going to implement when reloading next time.
FG instead of FFG
Way less compression on powder.
Let them leads stick into the rifling.

Thanks Guys this is one damn informative site. Ken.

wills
05-14-2006, 10:55 PM
Articles

http://www.researchpress.co.uk/targets/sandyhook.htm

http://www.riflemagazine.com/magazine/article.cfm?tocid=1094&magid=78

StanDahl
05-15-2006, 12:18 AM
Some of the guys on the old Shooters BPCR site were heavily into bottlenecks for BPCR - 40-70, 40-50, 38-56, 44-77...I have saved some of those threads - PM me if you have an interest. One finding was that compressing black powder wasn't working for bottle neck cases due to uneven compression, and that leaving it umcompressed worked better for extreme velocity spread. Some found it easier to work up a load with a BN case than a straight case. Stan

martinibelgian
05-15-2006, 10:23 AM
There is nothing wrong with these cases, but the rules we know for reloading straight BP cases do not really apply and if used will not really yield optimal results.
But they can be made to work, and actually are the final development of BP cartridges, with rounds like the 9.5 x60 mauser, 8mm Guedes, .402 martini-enfield and yes, even .303 british, originally a BP round...

Bigjohn
05-16-2006, 01:26 AM
By starting this thread, I had hope to pick up some information from the shooters at the (black powder) coal face on reloading BN cases and any advantages or disadvantages they may have. History has shown that BN cases can be shot as well as if not better than ST cases but history appears to have been cruel to the BN by the fact that they appear more as a specialized chambering in the modern firearms.

It is also unfortunate that the shooters who originally used them saw little or no value in recording the detailed information about reloading and shooting these cases or anything to do with shooting firearms of their era. Hence today, we are effectively rediscovering the wheel. Maybe they saw no need to record this information because each new development was seen as better than what they were using, and any such publication would have no value to anyone in the future. Let us not make the same mistake. Regarding those shooters that did publish material at the time, they seem in some cases to use terminology which is strange to us. Language does evolve as we progress.

IMO, If the rifle maker, the reloader/caster and the shooter have done their work correctly, then the form of the case should not affect the accuracy of the shot be it for game or target.

In this thread a post or two mention problems with compression of the powder. I can agree and see why compressing a charge in a BN case would give rise to problems. Take the 577/450 Martini; case neck will admit a compression post of 45 cal. only but the powder can spread out to approx. 577 cal.. All you would be compressing is a column .45 cal in diameter.

An option here would be to fill a BN case via drop tube and then apply case to centre stub of a vibratory case clean to settle it further??? An observation I have made on the powder charge in an original boxer cartridge for the 577/450. I have over the years needed to disassemble several of these rounds due to their poor condition. Under the projectile which was the paper patched version, the wad(s) were still sound and doing their job. Once I removed them I had to use a 'pick' to get the powder out. It was not solid as in one lump but simular to powder clumping, it came out easily but would not pour. The powder was still potent as I burnt it off afterwards to dispose of it, it could have been placed in and ML and fired with out problems.

Some of the problems the British experienced with this cartridge could have been due to fouling as IMHO there is NO effective control of fouling within the case. They were loaded with a wax cup between two millboard disc's immediately behind the projectile. There is a train of thought that they may have applied lube to the paper patch but I have found none that could be effective in controlling fouling. Maybe if the British had bought several Ideal 457125 molds and used a lubed cast projectile instead.:kidding:

There is another aussie shooter who posts here, B.A. Wallace, and who shoots the Martini rifle with a cast projectile. It may be worth our while to ask him for some details.

Fouling is known to effect accuracy to some degree and if we are aware of how to manage it we should achieve our aims. I would be one person who would line up for a BN BPC Rifle if they were available more than they are at present. I have the dimension drawing here for the chamber reamer in 577/450, all I need now is an action, a barrel and some funds. Oh I have some cases too plus the molds.

It does seem a bit of a shame that the shooting scene is 'Hogged' by the ST cases but with a bit more work maybe that could be turned around. I know they are out there but we don't seem to hear much from them.

martinibelgian
05-16-2006, 05:25 AM
IMO, If the rifle maker, the reloader/caster and the shooter have done their work correctly, then the form of the case should not affect the accuracy of the shot be it for game or target.

I agree - and adoption by major military powers should indicate that there was no disadvantage to using the BN case, be it fouling or accuracy

In this thread a post or two mention problems with compression of the powder. I can agree and see why compressing a charge in a BN case would give rise to problems. Take the 577/450 Martini; case neck will admit a compression post of 45 cal. only but the powder can spread out to approx. 577 cal.. All you would be compressing is a column .45 cal in diameter.
Which in all probability is the reason for the erratic performance
An option here would be to fill a BN case via drop tube and then apply case to centre stub of a vibratory case clean to settle it further???

Yes, that would certainly be an option, although not with 577-450, where one would rather look into ways of getting less powder into the case - modern drawn brass will easily hold 95-100 grs of Swiss Fg, without any settling whatsoever

An observation I have made on the powder charge in an original boxer cartridge for the 577/450. Once I removed them I had to use a 'pick' to get the powder out. It was not solid as in one lump but simular to powder clumping, it came out easily but would not pour.

Could just be age and/or moisture - but the original cases had less capacity than the modern brass

Some of the problems the British experienced with this cartridge could have been due to fouling as IMHO there is NO effective control of fouling within the case. They were loaded with a wax cup between two millboard disc's immediately behind the projectile. There is a train of thought that they may have applied lube to the paper patch but I have found none that could be effective in controlling fouling.

The bullets, including paper patch, were actually dipped in molten beeswax and then passed through a die to remove the excess - like most cartridges of the era
OTOH, one should also notice that most of the "fouling problems" also occured with defeats - Isandlwana reportedly had fouling Martini's, but Rorke's drift the very next day knew no real problems: strange, no??


Fouling is known to effect accuracy to some degree and if we are aware of how to manage it we should achieve our aims. I would be one person who would line up for a BN BPC Rifle if they were available more than they are at present. I have the dimension drawing here for the chamber reamer in 577/450, all I need now is an action, a barrel and some funds. Oh I have some cases too plus the molds.

I only have (and shoot) a few original 577-450's. However, when spec'ing a reamer, make sure to redefine it to whatever you want - original barrels were NOT .458 groove, but somewhere between 462 and 465. Also, if you go for accuracy, the throat should be redesigned: the original throat design emphasizes reliability, not accuracy

It does seem a bit of a shame that the shooting scene is 'Hogged' by the ST cases but with a bit more work maybe that could be turned around. I know they are out there but we don't seem to hear much from them.

I should have 2 new rifles online soon - 8mm Guedes and 500/450 #2 Musket. Martini's, of course![smilie=1:

Cliff
05-16-2006, 08:52 PM
Don't forget the 11MM Mauser which is a proven cartridge. They did use a paper patched bullet and got good accuracy, with mine (smokeless-sorry) it will do under an inch at 100 yards. Also Mauser did a lot of experimental work and did come up with the 9.5X60R which was claimed to be the most efficient designed case and caliber for black powder. It was only available for a few years and used by Turkey, until smokeless powder pushed black out of the military. The ballistics looked good using 70 grains of black powder for a velocity of 1758 FPS on a 285 grain bullet. These were used in the Peabody-Martini as well as the Mauser bolt action of the time. ATB

martinibelgian
05-17-2006, 04:39 PM
Yes, the Mauser BP rounds do have a reputation for accuracy - the 11mm has good accuracy potential, and the 9.5 is Herr Mauser's idea of the perfect BP round. I'm not sure it will get advertised velocities, but even if it comes close, it would be impressive... And a cartridge that was standard military issue in a major military power of the time for sure would not have been accepted had there been fouling issues or similar with it...

Bigjohn
05-17-2006, 08:16 PM
G,day again from Downunder.......In reference to the cartridges I had to make safe; age, moisture and other effects could have contributed to the powders condition. The fact that one could have loaded it and shot it off is a statement for it's resilience.
I have never been able to find any written report or book on the Battle at Rorke's Drift. At this time I do have a copy of the movie but it is known that some producers use a little bit of artistic licence and it is difficult to determine if any was taken in the movie. The only other material I have seen on the battle was a program which refered to what happened to some of the survivors after the battle.

As to fouling being the cause of the defeat at Isandlwana, with out historical data I could not comment but I do believe they had trouble opening the ammunition boxes due to an alleged lack of screwdrivers, and hence supply problems to the soldiers on the line. But I was not there and I don't think there were too many survivors, unfortunately, on the British side.

One advantage I can see with the BN case is powder capacity in a shorter case. As to capacity (powder), have you experienced getting more than the 85grs into a case. I would have thought that due to the modern drawn case construction powder capacity would have been close to the originals (577/450). I know the 45/70 Govt case in the modern drawn versions has a lesser capacity due to the thicker base. Currently I struggle to get any more than 62grs into my cases (WW & Rem).
Boxers construction methods used a base wad to hold the roll case together. I have not tried this but I believe it is possible to almost completely disassemble boxer cases by removing the primer? I am not going to take down my one surviving original sample just to prove it but if I get some more to make safe maybe?


Yes I am aware that the bores on the Martini's were aleast .463 and the molds I have cast for that diam. I would envisage attempting to obtain a .458 barrel for a target rifle and keep the other models etc for the Military versions. Two batches of cases, one for target, the other for the Military.
John

martinibelgian
05-18-2006, 03:07 AM
Bigjohn,
BP when stored under decent conditions usually will not deteriorate, and will keep quite a while - so I would presume the powder you emptied would have been perfectly useable. Also, If you look around, you will find quite a bit of literature on Isandlwana and Rorke's drift, even DVD's... Just have a look at the Martini Henry forum on gunboards.com. Or do as I did, and go there!:mrgreen:
The original 577-450 case was foil, and usually quite wrinkled and undersize, also lined with paper - so case capacity was considerably less than modern drawn brass.
BTW, as to 45-70, with the right bullet and powder, you can get considerably more powder in the 45-70 than 70 grains.... My LR load is a 521 bullet with 80 grains of Swiss 1 1/2 Fg: WW brass, unsized, a bit of compression...

At to a 5770-450 with a .458 barrel: don't forget to redimension throat and neck on your reamer, otherwise you'll run into trouble with a chamber dimensioned for
.463 and a .458 bore - particularily as the reamer is already on the 'generous' side for the original bore! You can forget decent accuracy if the bullet has to be squeezed down considerably to enter the bore...

Bad Ass Wallace
05-18-2006, 07:20 AM
G'day all,
Yeah, I'm probably the only fool whose interest in 577/450 has lead me to spend more money to buy bollit moulds than the original rifle cost:roll:

Present load is 80gn Wano 2P black powder settled in the case buy touching the centre stub of the case cleaner, then add "Polenta" (corn meal) to within 3mm of the top settle again, card wad then a 520gn .462 CBE bullet liberally finger lubed with straight "Lanotek" grease.

This load has shot a 10shot off bench at 50m of just one ragged hole 1.25". Supprised myself (and the other competitors) in '04 by shooting a 141.13/150 in a service rifle match. Even got a 9/10 pigs on the sillywet range one day. That this load shoots therefore is without question but just why.

20years ago, I had all the same problems you have all described, excessive fouling and blamed the powder. I bought Goex, Wano, Swiss, C&H - FG, FFG, FFFG, Pryodex etc. Nothing would shoot well. Then I bought an adjustable PP mould and started to get results but only if I cleaned after each round. This PP with 2 wraps of 'bank' 60gms paper measured .463".

I then bought a CBE (Cast Bollit Engineering) mould #462.500. Fired unsized and just lubed they really started to group well but only with excessive cleaning. This was very puzzling because all the time my 45/70's would shoot 20-25shots with no such problems.

Then I discovered "Lanotec". This 'off the shelf' grease is made from sheeps lanolene (wool grease) and is really slippery, waterproof, and KEEPS BLACK POWDER FOULING SOFT!:drinks:

Now I can shoot a whole 40 shot match without cleaning and at the end, a clean dry patch pushed through the bore brings it back to bright metal without scrubbing. The problem all the journey was simply to get a lube that will keep the extra fouling of a BN case soft :Fire: :Fire:

http://img.photobucket.com/albums/v152/BAWallace/BPCartridges.jpg

http://img.photobucket.com/albums/v152/BAWallace/My_577_450_2.jpg

martinibelgian
05-19-2006, 03:10 AM
B A,

How about telling us some more about that grease? I found the website of the company, but apparently you Aussies keep it all to yourselves.... If the stuff is as good as you claim it to be, then I would be very interested in trying it. What are the other components besides lanolin?

Bad Ass Wallace
05-19-2006, 06:08 AM
Here is the details. Where do you live?

http://www.conbear.com/Lanotec%20MSDS%20Type%20A%20Grease%20version%201.p df

It says 90% lanolene so there must be some other smart operator in your part of the world with similar stuff. I also use the spray for long term storage on the collector pieces; it don't run off like gun oil:-D

45 2.1
05-19-2006, 07:22 AM
How about a picture in the container, on a boolit and otherwise so we can see just how stiff or goey this stuff is????

Bigjohn
05-20-2006, 11:39 PM
G,day again everyone.... I've been up to my armpits in reloading these last couple of days; 9mm Para. With my large hands they are a PITA to reload and single stage as well. Still not finished yet and would you believe it, I won't be firing one of them.

Back to the topic we are discussing; BAW:- Good to see you pop in and post in this thread, I was hoping you would having seen your posts elsewhere on the 577/450 Martini. I have never thought of LANOTEK, I know some farmers who have used it as a rust inhibitor but as a BPC Lube! Worth a try.

These past few days I have had my case cleaner working overtime but no chance to try powder settling with it, next batch maybe.

Martinibelgian:- I believe you mentioned case cleaning with an ultarsonic cleaner? I presently clean the 45/70 with test tube cleaning brushes and I have wondered about the bottleneck cases. I purchased a small Ultrasonic cleaner to try (Small outlay cash wise), it has two power settings but did not seem to want to work for me. Any hints? I have friend up north with a large ex medical service unit. Several years ago there were a couple of articles in TARGET GUN from the UK on the Subject of BP case cleaning. I believe I still have these issues in my library must find them and refresh my memory.

45 2.1 :- I will see what I can find out for you on Lanotek. Us aussies can be a resourceful lot, need to be at times due to the difficulty of finding a source of materials which other countries can buy of the shelf. With have some good home grown mold and barrel makers down here. I have one of CBE's adjustable PP bullet molds, a work of art. :castmine:

:drinks: Until later,
John

martinibelgian
05-21-2006, 02:58 AM
Bigjohn,

Ultrasonic case cleaning is NOT magic, but it requires the right parameters to be efficient:

temperature
solution

I use a lightly acidic solution with an industrial cleaning product, but I presume something like citric acid would work too, with some detergent added. 2-3% concentration is ample.
Also, you need a warm solution (somewhere between 40-60 Celsius), meaning a unit with a heater, preferably big enough (2-3 liters minimum, best with 2 transducers - the medical units. are good for the purpose) My routine is as follows:

decap
rinse in warm water
dump in cleaner at 50 degrees for 30 minutes
when done, thoroughly rinse in water with detergent to neutralize
dump in tumbler for 20 minutes


No need to handle each case individually, and scrub the insides - serious saving in both time and aggravation, AND the insides are MUCH cleaner.

349-C
07-07-2006, 12:07 AM
Bottle Neck vs Straight Tapered Cases

I don't think that straight cased BP cartridges are intrinsically more accurate than bottle necked cases, but straight cases do seem to produce less troublesome fouling.

Several years ago, John Schoffstal at C. Sharps Arms told me that a load of 65 grains of GOEX BP in a 40-70 bottle necked case produced no more fouling than a similar load of BP in a 40-70 straight case. But he cautioned that a load of 70 grains which would be well tolerated in a 40-70 straight case would produce a ring of hard fouling right in front of the mouth of a 40-70 bottle necked case.

During the Frankford Arsenal experiments that led to the development of the 45-70 government cartridge, Major Treadwell found that a 70 grain load of musket powder and a 400 grain bullet in a bottle necked case produced a breech pressure of 18,500 psi, while the same load in a straight case produced only 16,300 psi, a difference of 2200 psi or 12%.

Althoughconventional wisdom says that case shape has little effect on the peak pressure generated by a load of smokeless powder, it appears that this is another area in which BP behaves differently from smokeless. We could speculate why bottle necked cases cause increased pressures with BP, but we won't really know until some sophisticated ballistics lab decides to investigate the question.

Bill Knight said that the 19th century "rule of thumb" for determining whether a given load of rifle grade powder would produce excessive fouling was to multiply the caliber by 1.5. If the powder weight is increased beyond this "rule of thumb" amount, fouling problems will become significantly worse. For a 40 caliber, the rule of thumb maximum would be 60 grains, for a 50 caliber it would be 75 grains.

This multiplier of 1.5 applies to rifle grade powders, which have a density like modern GOEX. For a softer, faster burning sporting powder like Swiss, use a multiplier of 1.4. For a denser, slower burning musket powder like Elephant, use a multiplier of 1.6. According to Pete Mink's experience, a 50-70-450 loaded with dense musket powder can shoot all day with minimal fouling build up.

If you have a load that produces excessive fouling in a bottle necked case, you could try reducing the load's peak pressure. That means using a little less powder. Or using a slower burning powder, one that is coarser (like substituting 1Fg for 2F) or one that is denser (like Elephant). You can also vary the bullet weight. Heavier bullets produce a little more fouling near the throat, while lighter bullets produce a little more fouling near the muzzle. Or you could find a miracle lube. Where can we buy lanotek in the US?

Another point about accuracy with bottle necked cases concerns the bullets. If bottle necked cases produce 10%-15% more peak pressure than comparable straight cases, that means the bullets you use with bottle necked cases will probably have to be a little harder or have a somewhat shorter nose than those you've used in straight cases so that the increased pressure will not cause nose slumping or bend the bullets in the bore.


All the best,

Dick Gunn

KCSO
07-07-2006, 10:52 AM
Ned Roberts in THE SCHUTZEN RIFLE and Mayer in his biography both said that the reason for the decline in popularity of the bottleneck cases was simply the ease of reloading and the availibility of everlasting cases for the straight cases cartridges. Some of the best Creedmoor records were shot with the 44- 77 Remington. And one of Neds early favorites for 200 yard shoooting was the 40-50 Sharps B/N.
All other things being equal I see no reason that a bottleneck case should be any less accurate than a straight case.

Idaho Sharpshooter
07-19-2006, 12:14 AM
not to offend MartiniBelgium, but the facts in modern day BPCRS simply do not support your conclusions worth diddly! There are a couple thousand shooters here in the 'States using all sorts of BP original cartridges with all kinds of bullet designs/weights and they share one uniform conclusion: BN cartridges absolutely have not been able to shoot targets that anyone wants to show anyone else.
Another thought RE your case design thoughts: the accuracy proponents here have evolved a generally supported theory; short and fat...is where it's at! It is why the 6mmPPC has supplanted the 6x47 (aka 6-222Mag) at copper-tubed bullet benchrest matches. Supposition is that a powder column that is no more than two and one half times the case diameter in height is optimal for ultimate accuracy on a repeatable basis in aggregates. It is reflected in cast boolits by the CBA where the 308X1.5 or 30BR reigns where rules allow. For the same reason the 308 is the king in production classes..particularly in a Savage 12BVSS with a twiddled with accu-trigger.

I have owned most of the worthwhile BP cartridges, most in single shot rifles. Currently a pair of LRE Shiloh Sharps reside in my vault, 40-65 and 45-70. A Hiwall and M1886 lever action Winchester in 50-110, a Stevens 44 1/2 in 38-55, and a Frank Wesson #1 long range in 38-90WCF being prepared for a run at the idea of being able to use one rifle for BPCRS and Long Range (800/900/1000yds) and the Quigley Match. The rifle has a 1:12" twist and will be shooting a 385gr Jones Creedmoor modified by me to insure it hits 385gr out of 20:1 alloy at somewhere near 1525fps with about 90gr of Swiss 1 1/2. I have a few others, but those are the highlights on the tour.

regards,

Rich aka the Idaho Sharpshooter

martinibelgian
07-19-2006, 02:57 AM
Rich,
Maybe it would also be worthwhile to look to the past - for a long time, the US LR top score (which apparently held quite long) was shot with a 40-90 What Cheer - A BN if there ever was one...
Also, the most popular and proven LR target cartridge in the UK was the .461 Gibbs, with a stellar accuracy reputation - BN again. 44-77 also was held in high esteem, and there are more examples. Most countries at the end of the BP era went to BN BP rounds, must have been a good reason for that. May be we need to relearn some lessons from the past?
Most people shooting BN cases do try to apply straight case loading technology to them, and that won't work for sure... It's a different beast, and needs to be handled differently. But they will work, and shoot accurately if you go to the trouble of learning what they like. Compression is something they don't like for sure.
My experiences with 500/450 #2 Musket and 577-450 have been quite positive (granted, after a rather steep learning curve) - but if you can get a bog-standard original military rifle to consistently hit the 1,000 yds target 1st time out with the original open military sights (firing a BN round), something must be working.
The next one I will be trying will be 8x60R Kropatschek, and there is a match rifle in #2 Musket in the near future...
I do have to admit that something like a 45-70 is easier to load for, but then again, where is the challenge in that? :-) Modern-day BPCR is indeed mostly about straight cases - call that the US tradition. But there might be other things that work too....

martinibelgian
08-03-2007, 03:48 AM
#2 Musket, 78 meters, prone with sling, no support, 7-shot group fired while developing a LR load for the rifle:

http://users.pandora.be/Gert.Claes1/2007-8-02-test%20LR%20load.jpg

90grs of Swiss no.4
Paper overprimer wad
550gr Minigroove bullet
CCI BR2 primer
Vegetable fiber overpowder wad

All of that assembled in Bertram #2 Musket brass, neck-turned and fireformed, bullet seated out to seat into the rifling. No neck tension used, bullets are a tight slip-fit into the fired cases. And yes, did feel that shot go to the left.

I rest my case...

MtGun44
08-03-2007, 01:49 PM
As far as why the US Army chose straight case, the lower pressure
compared to a comparable bottleneck is reported to be the reason. Also,
the actual force applied to the breech face is higher if you make the
casehead larger in diameter (press x area), WITH THE SAME PRESSURE,
so with a marginal strength action (trapdoor) this may be an issue -
more pressure AND higher force for a given pressure because of (likely)
larger head diameter.

OTOH, about 50 zillion Rem Rolling Blocks didn't blow up with many
different types of BP bottlenecks run by many different countries, each
no doubt with their fair share of knuckleheads operating them, so
the BP BN concept can't be unsafe. I wonder how the real world
strength of a RB REALLY compares to a trapdoor action?? We consider
both to be old and weak, but I wonder if they are comparable in
strength or is the RB actually a bunch stronger?

Bill

Cimarron Red
08-20-2007, 07:56 AM
Martinibelgian,

I have no experience loading or shooting BN cases, but I have shot with and spotted for some very good shooters who have done so with great results. For example, the current long-run record holder on turkeys (32) in BPCR silhouettes used a .40-50 SBN. I also agree that different loading practices are called for when loading BN's.

But most shooters in the BPCR silhouette game prefer to concentrate on the challenges presented by the shooting, not the loading. Others have different priorities and that's fine for them. For me silhouette shooting is plenty difficult without the extra loading challenges.

martinibelgian
08-20-2007, 01:34 PM
CR,
It actually is no more a challenge to load for BN rounds once you know what to pay attention to - load development time is essentially identical, and you can still concentrate on shooting. FWIW, the very 1st test load I tried in the rifle shot like a house afire! I even used it to win a match... The very next one did the same. If anything, this rifle has been easier developing loads for than my 45-70.
No, the issue is rather that most shooters want to be certain that have a performance-proven cartridge, so they go whith whatever shoots well nowadays, and hesitate to try anything else. Not me...

Cimarron Red
08-20-2007, 02:12 PM
MB,

I agree that most shooters hesitate to follow lightly-traveled trails -- me among them. Some day I may be overcome by the urge to try a BN cartridge. Thanks for all your insights

martinibelgian
08-21-2007, 05:52 AM
Should you ever decide to go that way, pay particular attention to reamer design and tolerances - quite a few of the 'more exotic' rounds can be a bit faulty in this respect, which gives them the reputation of troublesome rounds. However, with everything correctly dimensioned....