777 3f Dram Equivalents

[JJohnson2023]

I am looking to figure out dram equivalents of 777 3f to 2f black powder. I'm looking at a 12 gauge velocity chart that is denoted in drams, and would like to match these loads with 3f 777. What would be the best way to go about this? I would like 60, 70, 80, and 90 gr equivalents if possible. I appreciate anyone's input.

 

[BoomStick]

Divide grains by 27 to find drams, or multiply your chart's drams values by 27 to set your measure in grains. 777 and other synthetics say to use equivalent volume as you would for black powder. I'm sure there's plenty of debate if equal volume of a synthetic gives equal energy, but the makers of those products say they are.

Going from 2F to 3F is generally 10% less by volume. So 2 drams is 55 grains of 2F, or 50 grains of 3F -assuming 3F is more energetic and requires slightly less.

 

[BoomStick]

Should also mention in larger bores a larger grain size is preferred (again with some folks having a preference for 3F as well). Larger bore is more efficient at burning powder, so a smaller granule will burn even quicker and the pressure rises very quickly. This may cause shot deformation or holes in your pattern, depending on the load. All loads should be tested to ensure you're getting the density and velocity you want for your target distance.

A chart is a good place to start, but some validation of the results is needed.

 

[SDSmlf]

I am looking to figure out dram equivalents of 777 3f to 2f black powder. I'm looking at a 12 gauge velocity chart that is denoted in drams, and would like to match these loads with 3f 777. What would be the best way to go about this? I would like 60, 70, 80, and 90 gr equivalents if possible. I appreciate anyone's input.

Believe Hodgdon published info years ago when T7 came out (you will have to confirm, I didn’t check their website for current information) was to reduce your load by 15% (volume) as a starting point for similar ballistics.

The following has been repeatedly credited to Hodgdon for nearly 20 years, though I cannot say with certainty it is currently on their website.

Triple Seven is a high energy product designed to provide the muzzleloading hunter with higher velocities when used in the same VOLUME as blackpowder. To duplicate a blackpowder load velocity using Triple Seven, you must decrease the powder charge by 15%

Also remember reading that Hodgdon’s initial data was based on a 3F granulation, but again, you may want to confirm.

Personally, I found that the velocity difference between equal charges of T7 and Swiss was minimal, while there was a much greater velocity difference between T7 and Goex for example. It will come down to your tests in your guns. There is no simple chart to convert charge volumes across the board, there are just too many variables. Time to get out your chronograph.

 

[ppg1949]

Believe Hodgdon published info years ago when T7 came out (you will have to confirm, I didn’t check their website for current information) was to reduce your load by 15% (volume) as a starting point for similar ballistics.

The following has been repeatedly credited to Hodgdon for nearly 20 years, though I cannot say with certainty it is currently on their website.

Triple Seven is a high energy product designed to provide the muzzleloading hunter with higher velocities when used in the same VOLUME as blackpowder. To duplicate a blackpowder load velocity using Triple Seven, you must decrease the powder charge by 15%

Also remember reading that Hodgdon’s initial data was based on a 3F granulation, but again, you may want to confirm.

Personally, I found that the velocity difference between equal charges of T7 and Swiss was minimal, while there was a much greater velocity difference between T7 and Goex for example. It will come down to your tests in your guns. There is no simple chart to convert charge volumes across the board, there are just too many variables. Time to get out your chronograph.

SDSmlf is absolutely correct on stating Hodgdon tells you to use 15% less powder by volume on Triple 7. I’ve used the stuff since it first came out and the warning was on the can. Good luck.

 

[BoomStick]

Current hogdon literature doesn't mention reducing the charge for 777, but does say it's only intended for modern inlines and cartridge arms. Load data for loose 777 does not give patched ball or shot, just a bunch of sabots and bullets. Seems only pyrodex is recommended for sidelock muzzleloaders.

 

[TFoley]

Current hogdon literature doesn't mention reducing the charge for 777, but does say it's only intended for modern inlines and cartridge arms. Load data for loose 777 does not give patched ball or shot, just a bunch of sabots and bullets. Seems only pyrodex is recommended for sidelock muzzleloaders.

Pyrodex RS [Rifle and Shotgun] is the recommended stuff.

 

[JJohnson2023]

Current hogdon literature doesn't mention reducing the charge for 777, but does say it's only intended for modern inlines and cartridge arms. Load data for loose 777 does not give patched ball or shot, just a bunch of sabots and bullets. Seems only pyrodex is recommended for sidelock muzzleloaders.

I like 777 in my sidelock, but I think you need to use caps that are a little hotter to reliably ignite it, and 3f is easier than 2f to do so.

 

[JJohnson2023]

Thank you all for the responses. So theoretically when converting 2f BP loads to 3f 777 loads, it needs to be dropped roughly 15%. So a 60 grain 777 charge is equivalent to about 70 grains of black?
BTW the ratio I like right now is 1.4 grains of shot for every grain of 777, so 85 grains of shot to 60 gr of powder and 100 grains to 70 gr of powder.

 

[Poguetx]

There are plenty of universal weight converters available. Here's the first one that came up when I googled:

https://convertlive.com/u/convert/drams/to/grains#1

Just be sure you select GRAINS and not GRAMS!

And the comments are right about BP substitutes being equivalent in volume.

 

[JJohnson2023]

There are plenty of universal weight converters available. Here's the first one that came up when I googled:

https://convertlive.com/u/convert/drams/to/grains#1

Just be sure you select GRAINS and not GRAMS!

And the comments are right about BP substitutes being equivalent in volume.

I am under the impression that at least with 777 that is not the case. I have a brass shell loading manual that shows 777 being considerably hotter than BP and necessitating less powder for equal velocities with the same shot load.

 

[BoomStick]

Almost sounds like Hogdon changed their formula for 777 over time. Older literature says reduce volume by 15%, my 3-year-old bottle (I don't use it often) says to use equal volume but not for cartridges, and current info on website says only for modern inlines and cartridges.

I suppose one reason why I don't use it often...