Black Powder Pressures and Velocity chart
 

Hi,

I re-found this information amoungst my "pile o' stuff". I though perhaps it might find some interest here. I readily admit it is fairly old. I found it in a Nov 1993 issue of Guns and Ammo. And it only tests Real Black and Pyrodex (hey, it was all there was back then:D). I wish I could scan and insert the pressure curve chart. It's quite a bit slower and lower than modern smokeless powder.

Bullet Powder Charge Velocity(fps) Pressure(psi)

435gr Buffalo 90grs Ffg 1290 8100
100grs Ffg 1350 10,000
110grs Ffg 1430 11,700
120grs Ffg 1490 12,600

435grs Buffalo 70grs Pyrodex RS 1350 10,100
80grs Pyrodex RS 1435 11,800
90grs Pyrodex RS 1500 13,600

435grs Buffalo 80grs Fffg 1300 11,800

435grs Buffalo 70grs Pyrodex Select 1300 9200
72.5grs Pyrodex Select 1395 12,000
75grs Pyrodex Select 1500 14,600

Speer 225gr 90grs Ffg 1520 6000
.44 JHP in 70grs Pyrodex RS 1615 7000
MMP .54/.44
White Sabot

Test rifle: Knight .54cal barreled action. Direct reading piezo-electic pressure pickup and a strain gauge connected to an Ohler Model 43. Tests conducted by Bob Forker

Dale

RE: Black Powder Pressures and Velocity chart
 

They seem pretty low no wonder they are pushing the envelope higher these days. I would love info on modern rounds I fear they do not give us that info to save us from ourselves. lol!!!

RE: Black Powder Pressures and Velocity chart
 

I personally have no desire to shoot some of them big concials with that much powder behind them. But the information is real interesting. The thing that I find amazing is the down range energy of them big conicals at say 100 yards compared to most other projectiles...

good information..

RE: Black Powder Pressures and Velocity chart
 

Hi,

Sorry about the formating of the chart[:@]! I didn't check it after I posted it. My fault!

cayugad, them big old lead slugs really carry well down range. My 15yr old CVA Hawkens really likes the 385gr Hornady GreatPlains bullet. But the recoil with that skinny little brass buttplate can be quite painful!! I use 80grs of FFg under them for about 1100fps. More than enough energy to shoot clean through a 170lbs deer at 150yds.

Dale

RE: Black Powder Pressures and Velocity chart
 

I made the mistake of shooting some 426 grain Buffalo Bullet conicals one time out of the T/C Renegade .54 caliber and stuck 110 grains of Pyrodex Select under that. Renegades are a great rifle but the stock design will bite you in the cheek bone if the recoil is strong. I walked around for three days with a sore face from that one...

I did the same thing. I dropped them to 80 grains..

RE: Black Powder Pressures and Velocity chart
 

I was told by one of the techs at Knight a few years back that the pressures generated by the magnum loads (three Pyrodex Pellets with a sabot) ran around 30,000 c.u.p.

RE: Black Powder Pressures and Velocity chart
 

Hi,

I didn't think about this when I posted the chart. But pressure ratings and measurements are often taken by different methods and use different scales. Unfortunately, there is no way to convert one scale, (say psi to CUP), to another. And there is no standard method from one manufacture or country to another. An example, is British proof pressures for guns are often given in LUPs (lead units of pressure). We used to use Cups (Copper units of pressure) in this country. Now due to the avaialbility of piezo-electric sensers, we've pretty much switched to psi.

So we have to be careful when talking about the pressures that a load might develope, to be talking about the same units of pressure.

Dale