Volume vs weight 777

Thanks for all the replies here everyone. Based on your replies I have done some more research. Hodgdon says that "by volume" triple seven has about the same energy as black powder. But it weighs approx. 70% less because it's less dense. I want to shoot 120 grains of powder. 120 grains x 70% = 84 grains. So I think I will start with a weighed charge of 80 grains. Does this sound appropriate??

One person in my reading says that 100 by volume 777 weighs 77 grains. But maybe his measure is large or maybe hodgdons estimate is conservative. My muzzleloader will shoot 150 grains so aiming for 120 grain equivalent I believe I should be safe at a weighed 80 grain charge. I'd just like some opinions.

Thanks
 
For me............. I would be very skeptical about the 70% ordeal and wouldn't trust that. Dang, I can't find that conversion number.......

What I would do, which I'm not suggesting you do...... I would make sure that I had an accurate volume measure first, which can be a chore in itself. Over the years I've found that some can be off considerably. I had one that was actually 30grs heavy. In other words, if I'd have use that measure and wanted a maximum charge of 150grs, it would have actually been equilivent to 180grs. Dangerous! It appears that the one that is most accurate made today, is the T/C see through volume measure. In my experience, which may not be right so take it with a grain of salt, I verify my volume measures with actual Goex 2f. However..... I don't shoot T7 and only shoot BH209.

Then I would set the measure at 100grs and fill it 10 times, weigh each charge and record them. I would then average the 10 different weights and that would give me my starting point and the math will take over from there.

If I confirmed a volume measure by using actual 2f at 100grs, 110grs and 120grs, I would use the same process in confirming my 120gr preferred load.

However....... I AM NOT RECOMMENDING YOU WEIGHT YOUR CHARGES. YOU SHOULD FOLLOW ALL RECOMMENDATIONS OF YOUR RIFLE MANUFACTURER AND PROPELLANT MANUFACTURER. Safety first.....

I'll ask a couple guys I know....
 
777 is the only powder I have right now and I hate to go buy a powder I'm not planning on using just to check my measure. Measures vary so much how do you trust one. I guess I could go buy the clear one. Just seems like a waste to spend $20 to use it 5 times. I feel like weighing my powder would have to give me better accuracy than throwing compressed pellets down the barrel. I just need to find out how much to weigh.
 
777 is the only powder I have right now and I hate to go buy a powder I'm not planning on using just to check my measure. Measures vary so much how do you trust one. I guess I could go buy the clear one. Just seems like a waste to spend $20 to use it 5 times. I feel like weighing my powder would have to give me better accuracy than throwing compressed pellets down the barrel. I just need to find out how much to weigh.

I got a feeler out there........

Read this.......... http://www.thefreelibrary.com/Hodgd...corrosive+(almost)+muzzleloader...-a087413404
 
I appreciate the help. I did notice in that article that they tested the weigh / volume with 60 grains volume and it weighed 42 grains. I'm looking for 120. Twice that so the 84 grains I came up with earlier sounds appropriate to me.
 

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BP Conversion Sheet (revised December 2012)

Another....................

777 is very energetic, and should not only be measured in a VOLUME measure, but the volume charge should also be reduced 15% in FFg and 20% in FFFg as compared to FFg Black Powder or Pyrodex RS by VOLUME for equal velocities. In other words you get more bang for your buck because not only do you use 15% less VOLUME, but it is also 23% less dense by WEIGHT.

Example 1:

100 grains VOLUME 777 FFg = approximately 77.7 grains WEIGHT 777 FFg ( +/- depending on storage, humidity, Lot #, and volume measure used. It could be anywhere from 73 to 78 grains weight in my experience.)


Example 2:

100 grains VOLUME FFg Black Powder (100 grains WEIGHT +/- 5 grains approx) = 85 grains VOLUME (66.04 grains WEIGHT) 777 FFg. This is where your more bang for the buck starts to come in.


Example 3:

100 grains WEIGHT FFG Black Powder = approximately 66.04 grains WEIGHT 777 FFG.


Example 4:

7000 grains WEIGHT in a pound. Basically "70" 100 grain VOLUME/WEIGHT charges in a pound of Black Powder FFg. A pound of 777 FFg should net you "105" 85 grain VOLUME (66.04 grain WEIGHT) but (100 gr VOLUME equivelant) charges as compared to black powder or Pyrodex RS.



So if you want to convert any of your Black Powder VOLUME/WEIGHT charges, always measure a sample of 5 - 10 charges of 777 FFg by VOLUME first, then reduce by 15% VOLUME , then use that average for your WEIGHT measurement.


I hope I didn't lose you, 777 and Blackhorn 209 are almost identical in energy by VOLUME, but they are definately more energetic than Black Powder, Pyrodex or other BP Substitutes. If I did lose you, please ask for clarification. Make sure that young man gets a VOLUME powder measure and reduce loads by 15% -20%.
 
Thanks for all the help. I think I'll weigh some charges at 75 & 80 grains and give those a try. From all the reading and research you've helped me acquire I'm confident these will be completely safe in my gun. Both should be well under the 150 grain magnum load my gun is rated for. Ill post up some results when I get time to shoot them.
 
I second the suggestion that you trash the 777 and go to BH 209. Its cleaner, more consistent and really performs well. The BH209 web page contains sugested loads for a wide variety of bullets and a lot of other valuable info. such as suggested primers etc. They also sell charge tubes calibrated for BH 209 by volume to avoid any issues about overloading etc. I have 3 Knights, a Disc Elite, a Master Hunter and a Long Range Hunter all 50 Cal and all using bare primer conversions. I have tried almost all the saboted bullets on the market except for Knight's new Bloodline. I hunt west Texas where 150 yd plus shots are the norm rather than the exception. For this year I'm using 2 different loads. I use 110 gr. by volume BH209and a CCI 209M primer for both. One load is Hornady's 300 gr. SST and either MMP's or Hornady's 3 pedal easy load sabot. For the other, that I just use in my LRH and I use Harvester' s 300 gr PT Scorpion and their black crush rib sabot. I can routinely count on a sub MOA 3 shot group at 100 yds with all 3 rifles. Best group to date .297 inches. Both bullets do a great job on WT deer and the occasional Axis or Fallow we see on the lease. I use the 300gr over the 250 gr bullets because of a better Ballistic coefficient and better retained enegy down range. I sight in all by riflrs at 3" high at a 100 yds and that keeps me at point of aim out to 175 yds.
 
I thought I read somewhere that you have to have a special breech plug and primer to reliably set off BH209. Is that true? If so where could I get one? Or would it have to be special made?
 
I thought I read somewhere that you have to have a special breech plug and primer to reliably set off BH209. Is that true? If so where could I get one? Or would it have to be special made?

I believe you stated you have an Optima? Well CVA has behind the ball on propellants for a long time and still are.....

You can buy a replacement breech plug for your CVA to shoot BH209.... and it requires it. I think you can buy them right from Western (BH209).
 
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