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Posted By: LGF Curtis and Harvey BP modern equivalents - 02/27/21 10:07 PM
The charge card for my 1885 10 bore specifies Curtis and Harvey No. 4. What would be the modern Goex equivalent?

Thanks.
Posted By: SKB Re: Curtis and Harvey BP modern equivalents - 02/27/21 10:14 PM
I bet you can get 1&1/2 F Olde Eynsforde to work out for you.
Posted By: pamtnman Re: Curtis and Harvey BP modern equivalents - 02/28/21 05:25 AM
LGF: What SKB says. Olde Eynsford 1.5FG is pretty much the best modern equivalent to the old rifle powders. Swiss 1.5 is really nice too, just more expensive
Posted By: LGF Re: Curtis and Harvey BP modern equivalents - 03/01/21 07:55 PM
Thanks Steve and pamtnman.

This weekend I chronographed a dozen 10 bore 3.5 and 4 dram loads with 1.25 and 1.5 oz shot, trying both Goex F and FF in RMC shells with lubed fiber wads. The Pro Chrono works fine for nitro loads but I got nonsensical readings for half the BP shots; the other six were in the 950-1000 fps range, with loads that should yield around 1200.

Two questions: 1) I have not found instructions for chronographing BP shotgun loads and would be grateful for advice; and

2) given the poor reliability, I have no idea if the 950-1000 readings are accurate. If they are, could the low speed be a result of using Goex rather than a higher grade BP?
This does not address your question, but should be of interest
1896 Rules of Proof Black and Nitro powder Service and Proof Charge Pressures
https://books.google.com/books?id=inQCAAAAYAAJ&pg=PA296&dq

[Linked Image from photos.smugmug.com]

Curtis & Harvey “T.S.” (Treble Strong) No. 6 (84 grain = 3 Dr. Eq.) was coarse Black Powder somewhat similar (but not equivalent) to Fg.
“T.S.” was developed in 1871 for the .577/450 Boxer-Henry cartridge used in the Martini-Henry rifle. It was a precursor to “R.F.G.2” (Rifled Fine Grain 2) manufactured at the Royal Gunpowder Mills, Essex, adopted in 1873.
C&H, “T.S.” No. 4 (82 gr. = 3 Dr. Eq.) medium grain similar to FFg
C&H, “T.S.” No. 2 (72 gr. = 3 Dr. Eq.) fine grain similar to FFFg.

Sporting Guns and Gunpowders, “Tests Of Strain On Breech Actions”, 1892
1 1/4 oz. 3 1/2 Dram Bulk Smokeless Pressures in 2 3/4” case
https://books.google.com/books?id=inQCAAAAYAAJ&pg=PA86
Long Tons/ sq. inch converted to PSI by Burrard’s formula
(Proof) with 6 1/4 Drams “Tower Proof” Black Powder and 1 2/3 oz. shot – 4.51 Tons = 14,034 psi
3 1/2 Drams Curtis & Harvey’s No. 4 T.S. Black Powder – 4.2 Tons = 12,992 psi
“Schultze” – 4.28 Tons = 13,260 psi
Posted By: Flintfan Re: Curtis and Harvey BP modern equivalents - 03/01/21 08:59 PM
I've never done it, but when I was reading Sherman Bell's articles regarding his testing of black powder loads he mentioned having to make some sort of cardboard shield with a small hole cut into it that he fired this loads through before they passed through the chrono. There is so much ejecta with a blackpowder load that it would cause havoc with the chronograph, like you found.

Unfortunately I don't remember any specifics such as distance to the cardboard shield or the shield's distance to the chrono, and he might not have given any.

Might be a starting spot for some experimentation though.
It's not that difficult.

Pick a day when there's some wind.

Place the chrono about 6 feet away, at right angles to the wind.

Done.
Posted By: KY Jon Re: Curtis and Harvey BP modern equivalents - 03/02/21 03:59 PM
Use a baffling board and set your chronograph about six feet away is the only way I was able to measure black powder loads. To check my results I shot a couple smokeless loads I had previously tested across the same setup for comparison. If a 1200 FPS read 1090 FPS in my new setup I knew the black loads were most likely understated a bit as well. Mine were about 10% understated but yours may vary.
Posted By: LGF Re: Curtis and Harvey BP modern equivalents - 03/02/21 07:30 PM
Thanks very much for all the advice. I got the expected results when firing 1200 fps smokeless loads so don't know how to interpret the results from the 50% of BP loads that produced any data at all. Jon, not sure what you mean by a baffling board - similar to the shield mentioned by Flintfan?
Posted By: Lorne Re: Curtis and Harvey BP modern equivalents - 03/03/21 05:20 PM
Eynsford should work fine, but is significantly more expensive than Goex or Schutzen, or Graff (current Goex, used to be Schutzen) if you can get it. If you're going through a pound or two a year it's not an issue, but I go through a can in a week or ten days during the summer, and I find that Schtuzen, Goex, and Kik (when it was available) all worked fine for shotgun (I've connect on a website with people who swear by skirmish powder for shotgun). For match shooting with a rifle, I would go right to Swiss or Eynsford.
Posted By: KY Jon Re: Curtis and Harvey BP modern equivalents - 03/03/21 05:50 PM
Yes. I built mine with two boards about ten inches apart. Hole bored through both. You only need one. Boards were 90 degrees to flight path of load. Shot passes through the hole. They limited the amount of non shot stuff which passes over the chrono screens. Without them the mass took too long and gave results which were extremely slow. Shot might have been 1100 fps but because of the entire train it was recorded as 820 fps. With the baffle I got just under 1075 fps. You need to figure adjustment in velocity because the screens are moved away from the muzzle. I love shooting black powder shells. I get a lot of WHAT the HECK was that questions.
Posted By: LGF Re: Curtis and Harvey BP modern equivalents - 03/03/21 10:43 PM
Thanks Jon, I'll try that and report back.
Posted By: Flintfan Re: Curtis and Harvey BP modern equivalents - 03/04/21 01:02 AM
You may also want to try 3F as well. I have been shooting 4 1/2 drams of 3F Goex in a heavy Parker 10 gauge hammer gun for many years, and it performs wonderfully. I use 1 1/2 oz of bismuth, brass cases, and fiber/wool wads. Again, it was Sherman Bell that turned me on to using 3F in all shotgun loads. Through his testing he determined 3F was the closest granulation to matching the quality of "sporting powder" that was originally used in the late 19th century.

Never have been able to have them tested, and was always curious.
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