Gearhart -Owen Powder ?

[Uncle Mike]

Hi,I was just given a can of G-O "Superfine Black Rifle Powder". Its size is unmarked.Can states "good for muskets,pistol & shotguns" but f's faded only g visible. Is there a rule of thumb as per size (ffg,fffg,etc.)or should I just eyeball it by comparing it to a marked powder? Regards,Mike

 

[roundball]

Hi,I was just given a can of G-O "Superfine Black Rifle Powder". Its size is unmarked.Can states "good for muskets,pistol & shotguns" but f's faded only g visible. Is there a rule of thumb as per size (ffg,fffg,etc.)or should I just eyeball it by comparing it to a marked powder? Regards,Mike

That's a somewhat old powder made by the Gearhart-Owen company before it became GOEX (GO=Gearhart-Owen, don't remember what the EX stands for).
I for one don't know which modern made powder to compare it to if we even could...but based on your quotes, if it was me I'd treat it as if it was 2F and use some vary light 20/30/40grn charges to get a sense for what I had there...then adjust accordingly.

 

[Uncle Mike]

Thanks Roundball, for your info.I definately will take it slow if I use it at all,regards,Mike

 

The Ex stands for Explosive which is the Division of G-O that makes black powder.

If it's been stored properly then you should have no problems, I'm on my last can of G-O dating from 1973. With respect to RB I would suggest loading it as if it were 3F just to be on the "safe" side. G-O had some minor issues in the old days with pressures.

 

[roundball]

With respect to RB I would suggest loading it as if it were 3F just to be on the "safe" side. G-O had some minor issues in the old days with pressures.

That's exactly why I suggested 2F...it generates LESS pressure than 3F...3F burns faster and can jump pressure faster than 2F :wink:

 

[paulvallandigham]

If I remember correctly, back in those days, Gearheart Owen called their 2Fg powder " Rifle Powder," and the 3Fg powder " Pistol Powder". If you have current GOEX powder in either grade, put a bit of each from the cans on a piece of paper in clear light, and compare the two for granule size. I can tell the difference between my 3F and 2F powders, when they are placed side by side, so I think others can, also.

 

[mazo kid]

Just a guess on my part, but Paul states G-O called their 2fg powder Rifle powder, so I would think that if the can says Superfine Rifle Powder that it should be 2fg. UNLESS...the can was used for something else. Further testing is in order, first to find out if it indeed is black powder! Emery

 

[pamtnman]

Only 17 years later…recently I was gifted some obscure old, dirty, bp cans. All are open, all are partially full of black powder, pulled from an old barn here in central PA. A few of the cans have faint “Gearhart Owens” markings on them. One says “Rifle Powder” but when it is poured out, the grain size runs from dust to probably 4F, a few 3F size grains included. Quite varied and inconsistent. These cans and their contents must be from 1972-1974 range. If this powder were used in a rifle at any real volume, it would destroy the gun barrel. No wonder US military grenades with G-O powder fuses had premature detonation problems back then.

 

[OLUT]

Pamtnman, I think that your obscure, dirty G-O powder can with mixed grain sizes was reused ... As a REALLY OLD black powder shooter, I'm finally using up my vintage stock of powders. I'm currently using Gearhart-Owens FFg from 1976 and FFFFg from 1973 . Both cans are identical marked "SUPERFINE BLACK RIFLE POWDER" and also "SUITABLE FOR MUSKET, PISTOLS & SHOTGUNS" ; they differ only with the addition of the appropriate granulation marking. These powders both have the correct and consistent grain size and both still perform well in my muzzleloaders after 50 years. (Likewise, my old "Hodgdon- made in Scotland powder" is still good)