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huntingsgr8
06-06-2016, 07:13 PM
I'm looking to see if anyone knows the barrel pressure created by a full power 10 bore rifle load (10 dram, and 700gr round ball), I know that the modern pressure maximum is 11'000 psi for 10 gauge shotguns, but I was wondering what a heavy black powder load like that would produce in rifles. I've seen that particular load listed as a maximum, on average it seems that load would produce about 1500 fps.

Nobade
06-06-2016, 08:32 PM
10 Drams? Wow! I shoot 5 drams in my 12 bore and it's plenty. No idea what the pressure would be, but with a round ball it can't be too terribly high. Is this a muzzle loader or cartridge rifle?

-Nobade

huntingsgr8
06-06-2016, 10:28 PM
For a cartridge gun, I don't have one, but I'm curious.

Mk42gunner
06-07-2016, 05:25 PM
Sounds interesting, but I have no personal knowledge.

Maybe see if some of the European proof houses have any online info you can access?

Robert

Earlwb
06-07-2016, 06:11 PM
There is a book by Graeme Wright, "Shooting the British Double Rifle", third edition. It may have the information you are looking for. They do cover pressure testing for some of the guns in the book too.

But using something more familiar, the .45-70 for example, in the Trapdoor rifles, it developed under 18,000 psi. So I would think that the big double rifles, using black powder were probably in that same pressure range.

texasnative46
06-07-2016, 08:36 PM
huntingsgr8,

My guess is that IF you go to www.muzzleloadingforum.com (http://www.muzzleloadingforum.com) you will SOON have your correct answer. = The real muzzleloading experts hang out there.
(From personal experience, I can tell you that I get a lot of GREAT & CORRECT advice on that site & generally QUICKLY.)

What I find amazing is that a 10 gauge rifle was seen as a "firearm of moderate size" in the African hunting fields of the 19th Century. - Numerous well-regarded hunters of that era believed a 6 or 8 gauge double-rifle was "well suited to take dangerous game" & at least one professional ivory hunter had a 30-pound double-barreled TWO gauge, which fired a conical lead bullet of FIVE OUNCES.
(Even the THOUGHT of firing that monster makes my 69YO shoulder hurt!!)

yours, tex

Earlwb
06-08-2016, 04:39 PM
Quite a few of the fellows who fired the really big bore guns didn't do it any more than they had to, if that much. The recoil made them all gun shy. So they went with smaller caliber guns as quickly as possible when the guns became available.

Earlwb
06-08-2016, 08:42 PM
I was reading here http://www.armbrust.acf2.org/buffalo.htm
They were detailing loads for a 8 bore rifle. It had about 11,000 PSI chamber pressure using 10 drams of powder with a 880 gr round ball. So I think that your 10 bore chamber pressure is in the same range as the 8 bore rifle's chamber pressure.



Shell:
8 GA 3-1/4" Winchester Clear Plastic Yellow Plastic Base Wad (New)


Primer:
Win-209


Powder:
78 GR Alliant Blue Dot


Wads:
Gualandi 8 Petals Removed + 3/8" Hard Fiber + (2) .125 Nitro Cards


Bullet:
880 GR Round Ball Number 2 Alloy .850 Diameter


Crimp Roll:
OL 3.135


Volocity:
1563 FPS in 24" rifle
1636 FPS in 30" pressure barrel


Pressure:
11,070 PSI

texasnative46
06-08-2016, 09:37 PM
Earlwb,

I'm sure that you're correct. - In point of fact, there were SOME handguns that were built to very large BP rifle-caliber rounds.

Brigadier (later: Lord) Robert Baden-Powell, the founder of Scouting, had a double-barreled 8-gauge PISTOL when he was a CPT in the Boer War.

ADDENDA: Lord Baden-Powell's body servant killed a "night-prowling criminal" with the 8-gauge pistol. According to the Provost Marshal's report of the next day, the deceased prowler was "carried to his place of burial in 3 pieces".

Also a British COL , who was seconded to the Indian Army as a BG in the late 19th Century, had a FOUR-barrel howdah pistol custom-built in .577/450 Martini Henry caliber, for STOPPING wounded tigers/leopards at pointblank range, that fired the 2 top barrels with the front trigger & the 2 bottom barrels with the rear trigger.
(W.D.M. "Karamoja" Bell said of that 4-barreled monster, with typical British understatement, "The recoil & report of the weapon was considerable.")

yours, tex

Earlwb
06-09-2016, 07:32 AM
I think I copied the wrong data in the earlier post as it shows a alternative smokeless powder load. But in the article the highest pressures they got with the 8 bore rifle was 14550 LUP, at about 1494 FPS with the 1110 GR conical bullet using 10 drams of FFG Swiss and 12290 LUP at 1575 fps using a 880 grain round ball.

I think it was most impressive that they actually had a pressure gun to perform these tests with too.

But that smokeless powder load is sort of scary in its own right at them using 78 grains of Blue Dot smokeless powder and only getting around 11,000 PSI pressure with it. 78 grains is sort of phenomenal considering the little guns we normally use it in.

Ballistics in Scotland
06-10-2016, 05:04 AM
I think I copied the wrong data in the earlier post as it shows a alternative smokeless powder load. But in the article the highest pressures they got with the 8 bore rifle was 14550 LUP, at about 1494 FPS with the 1110 GR conical bullet using 10 drams of FFG Swiss and 12290 LUP at 1575 fps using a 880 grain round ball.

I think it was most impressive that they actually had a pressure gun to perform these tests with too.

But that smokeless powder load is sort of scary in its own right at them using 78 grains of Blue Dot smokeless powder and only getting around 11,000 PSI pressure with it. 78 grains is sort of phenomenal considering the little guns we normally use it in.





You also called that charge 10 grams, when in fact I think drams would be correct. A dram is about 27 grains or 1.77 grams. Anyone reading old books also has to beware of the apothecaries' drachm, occasionally spelt without the "ch", which is just over twice as big.

Ballistics in Scotland
06-10-2016, 05:41 AM
I'm looking to see if anyone knows the barrel pressure created by a full power 10 bore rifle load (10 dram, and 700gr round ball), I know that the modern pressure maximum is 11'000 psi for 10 gauge shotguns, but I was wondering what a heavy black powder load like that would produce in rifles. I've seen that particular load listed as a maximum, on average it seems that load would produce about 1500 fps.

10 drams is fairly heavy but safe in a rifle built to the nearly modern standard arrived by the end of the 19th century. 10 or even 12 is what Greener recommends for an 8ga. and only with spherical ball rather than the bullet of up to about 50% heavier that was sometimes used. He regards the 8ga with ball as the most useful weapon of this type, since with 20in. barrels it could be built to a weight of around 1½ pounds without undue discomfort. It was much handier than the 4ga. He says many sportsmen might prefer a large bore express (which meant black powder express when he was writing), and the advantages of the express were greater for 10ga downwards. The mathematics of weights and recoil would be the same for a 10ga as an 8ga.

He illustrates the group made with 8ga rifles, both made with 10 drams and ball. One in the "Field" rifle trials of 1883 is 2⅜
in. centre to centre at 50 yards, and another made in several sessions by a Mr. Henry of Saigon put 157 out of 163 shots in a twelve-inch circle at 110 yards. The 10ga was more popular in India than in Africa, as the elephants were smaller and less often hunted, and almost all the other hunting was of the tiger, leopard and deer species.

cpileri
06-10-2016, 06:25 AM
I own the book. ill check and report back


Sounds interesting, but I have no personal knowledge.

Maybe see if some of the European proof houses have any online info you can access?

Robert

Earlwb
06-10-2016, 07:33 AM
You also called that charge 10 grams, when in fact I think drams would be correct. A dram is about 27 grains or 1.77 grams. Anyone reading old books also has to beware of the apothecaries' drachm, occasionally spelt without the "ch", which is just over twice as big.

Thanks I corrected the typo earlier. yeah the measurements need to be carefully thought out before being used as the standards can change or be very different from today.