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View Full Version : PP and Metford segmental rifling



martinibelgian
03-25-2007, 03:01 PM
I wonder if the man was on to something... I just came back from the range, shot some cobbled-together PP rounds today - the bullet was harder than a woman's heart (50/50 lynotype/lead), patched to groove diameter, about 540 grs.
http://users.pandora.be/Gert.Claes1/Metford%20bullet.jpg
this was patched to groove diameter, seated quite deeply in the (45-70) case, compressing the 67grs of swiss 1 1/2grs quite a bit, without lube cookie, just a card overpowder wad - I only lubed the visible part of the patch (about 1/2" at most)
I shot 10 of these with just blowtubing between shots, and I was extremely surprised at the accuracy I got - I did have a horizontal spread, partly due to me no doubt, but these bullets sure wanted to group! Even the very last shots were showing no loss of accuracy at all!
What's more, when cleaning the barrel after 10 rounds, I was very much surprised at the lack of fouling in the barrel - actually much less than when shooting GG bullets. Basically, everything was wrong - bullet .451, patched to .458, hard alloy, no lube cookie, no wiping between shots - but it WORKED! I'm puzzled, but agreeably - and I'll try this again, even if I am quite sure after 10 rounds that this isn't a fluke....

45 2.1
03-25-2007, 07:01 PM
I wonder if the man was on to something... I just came back from the range, shot some cobbled-together PP rounds today - the bullet was harder than a woman's heart (50/50 lynotype/lead), patched to groove diameter, about 540 grs.
http://users.pandora.be/Gert.Claes1/Metford%20bullet.jpg
this was patched to groove diameter This is what saved you, you patched so you didn't need it to bump up., seated quite deeply in the (45-70) case, compressing the 67grs of swiss 1 1/2grs Swiss is fairly clean burning. quite a bit, without lube cookie, just a card overpowder wad - I only lubed the visible part of the patch (about 1/2" at most)
I shot 10 of these with just blowtubing between shots, and I was extremely surprised at the accuracy I got - I did have a horizontal spread, partly due to me no doubt, but these bullets sure wanted to group! Even the very last shots were showing no loss of accuracy at all! The patch cleaned most of the fouling out on each shot. If you do this again, try lubeing the whole bearing surface of the patch.
What's more, when cleaning the barrel after 10 rounds, I was very much surprised at the lack of fouling in the barrel - actually much less than when shooting GG bullets. Basically, everything was wrong - bullet .451, patched to .458, hard alloy, no lube cookie, no wiping between shots - but it WORKED! Wrong only in that you didn't use the methodology used with common blackpowder PP loads, BUT this is the methodolgy used with smokeless paper patched loads and it works well as you have seen. I'm puzzled, but agreeably - and I'll try this again, even if I am quite sure after 10 rounds that this isn't a fluke....

Buckshot
03-26-2007, 01:06 AM
..............You did pretty much what I do using PP'd slugs and smokless. A bore or bore+ .001" slug, wrapped to a over the patch diameter of .459". The barrel looks like it had just been cleaned and patched dry.

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

martinibelgian
03-26-2007, 03:26 AM
2.1,
What surprised me most was the fact that I could chamber without any problems and shoot with accuracy without cleaning between shots - the quantity of lube used on the patch was minimal, so basically there almost no lube anywhere in the equation. And still it worked... Common wisdom indicates that I would foul out after 2-3 shots, not being able to chamber the next round - which didn't happen: the last round chambered as easily as the 1st.
Mind you, this bullet and patch is something I believe was the brit technique of shooting PP with BP, at least as far as I could determine from contemporary writings and cartridge drawings (the bullet actually is a copy of the Metford match bullet of the late 1880's). And maybe that segmental rifling has something to do with it too... I will certainly explore this venue mor in depth!

45 2.1
03-28-2007, 09:16 AM
What surprised me most was the fact that I could chamber without any problems and shoot with accuracy without cleaning between shots - the quantity of lube used on the patch was minimal, so basically there almost no lube anywhere in the equation. I think its the paper doing the cleaning here. I suggested lubeing the whole bearing surface to keep to a minimize the papers abrasive properties. When this (paper patching and twist rates with black powder) was still in its infancy, steel slugs were also used via paper patching to use against other ships, so your hard slug isn't anything new. and still it worked... Common wisdom indicates that I would foul out after 2-3 shots That is the common wisdom (?????) of the current users (from past use on american bison), not what was developed and forgotten from the past masters of the paper patched boolit over 100 years ago in the long distance matches in England and America. They are the ones who knew a lot more than anybody now. We are just rediscovering what they used. Current reprints of participants methods do not touch much on this either., not being able to chamber the next round - which didn't happen: the last round chambered as easily as the 1st.
Mind you, this bullet and patch is something I believe was the brit technique of shooting PP with BP, take a look at the illustrations from some of the military ammo of the day and you really don't see a lube wad, a cupped beeswax wad yes, but not anything that is soft like they use now. If you experiment with those beeswax wads, you will find they don't melt or lubricate much, but scrap the bore and take up space. What needs to be found is what the long range match shooters did. at least as far as I could determine from contemporary writings and cartridge drawings (the bullet actually is a copy of the Metford match bullet of the late 1880's). Is it a true copy as to diameter? Do you have all the pertinent dimensions? And maybe that segmental rifling has something to do with it too... The segmental rifling appears to be a very good form for this use. I will certainly explore this venue mor in depth!

martinibelgian
03-28-2007, 10:47 AM
2.1, If you want to, I can send you a Kynoch shop drawing for a .45 500/450 #2 musket cartridge + bullet, giving dimensional info - basically, the bullet I used is a later version, but I applied the same design principles as in the Kynoch drawing to generate the Metford bullet copy - just PM me your email address...
Also, I gathered much info from J.H. Walsh's book (Stonehenge) piblished in 1888 - he mentions the use of unlubed PP bullets, and paraffin wads (even harder than beeswax), and Metford's claim as to being able to shoot without any lube... Not cleaning between shots, of course!
What I did gather is that there are 2 schools:
1. Bore diameter, pure lead of very soft, relying on upset (US)
2. Groove diameter, and harder (UK)
Mind you, I have no conclusive proof that this was in general use i nthe UK, just that Kynoch shop drawing giving me an indication...

45 2.1
03-28-2007, 10:59 AM
Also, I gathered much info from J.H. Walsh's book (Stonehenge) piblished in 1888 - he mentions the use of unlubed PP bullets, and paraffin wads (even harder than beeswax) They might be harder than beeswax, but they melt as fast or faster when flamed. and Metford's claim as to being able to shoot without any lube... Not cleaning between shots, of course!
What I did gather is that there are 2 schools:
1. Bore diameter, pure lead of very soft, relying on upset (US)
2. Groove diameter, and harder (UK)
Mind you, I have no conclusive proof that this was in general use i nthe UK, just that Kynoch shop drawing giving me an indication... This is the point that needs some illumination, if it can be found in print. PM sent also.

martinibelgian
03-28-2007, 01:01 PM
Bob,

I for one don't believve in the wads melting - you can even recuperate card overpowder wads, or patching paper without any burn marks (unless you have blowby!), and that stuff would flame quite a bit earlier. I have even recuperated lube cookies which to all intents and purposes were undamaged, just engraved with rifling. To me, there are 2 theories here (yes, again...)
1. lubeing the bore with the cookie at the barrel contact point
2. Scrubber wad, which, more like wipes the fouling out of the barrel, maybe leaving a thin layer or 'matter' preventing the successive fouling to adhere to the barrel walls.
Still, there is another factor - no lube, no 'soap' in the barrel when moistening (blowtubing) - and everyone tells me this is the way we can control fouling. So why can I shoot without one of the 'soap' ingredients? Maybe I should try sooting some bullets absolutely dry, to see what gives...

BTW, email reply sent with some files.

martinibelgian
04-01-2007, 07:50 AM
I just returned from the range, and shot the last 10 rounds of the PP ammo - however, this time I left the patches dry.

The rifle was my Greener GP .45-70 with Holbrook front and rear sights. The barrel on the rifle, as said before, is Metford segmental rifling, 1:18 twist.
Load information as follows:
Metford 540gr PP bullet (naked .451, patched up to .458) cast 50/50 lino/lead
Card overpowder wad
67grs of Swiss 1 1/2Fg
WLR primer
5-6 breaths between shots with the blowtube

All shots prone, with sling, no support. distance 78m, on the ISU pistol target. result?
Shot 1: 9, 12:00 (barrel fouler)
2: 9, 3:00
3: 8, 3:00
4: 9, 4:00 (after which I changed my position a bit...)
5: 10
6: 10
7: 10
8: 10
9: 10
10: 7, 4:00 (I pulled the last shot!)

the 5 consecutive shots in the 10 actually all cut the X-ring. Pity about that last one, that was a nut-behind issue :roll:

To me, this conclusively proves that in my rifle, I can perfectly shoot dry PP bullets with blowtubing only and without any loss of accuracy. All rounds chambered with perfect ease, and cleanup afterwards showed very little fouling in the barrel, and (of course) no lead. Unfortunately, I am not able to recuperate some patches after firing, but judging from the accuracy, I doubt whther there was any blowby
Remember, these were shot unlubed, no lube cookie either, no wiping - just blowtubing.