Reloading with Pyrodex - What am I doing wrong?

[senormik]

Hello all,

I'm fairly new to reloading, and have no experience with black powder or substitutes.  I'm shooting a Chaparral 1876 in .40-60 Winchester.  Firing Buffalo Arms smokeless rounds, I get about 1.5" groups at 25 yards.  But shooting my Pyrodex RS reloads, I'm ending up with about 8" groups at the same range.  Not sure what the problem is, but because the smokeless rounds seem to shoot tolerably well I figure that my problem must be with my reloads.  I'm using Buffalo Arms 210 grain .406 diameter bullets cast for this caliber, lubed with SPG.  I'm filling the case through a drop tube to the point at which the powder is compressed about 1/8 of an inch when I seat the bullet.  Not using a wad.  Federal 210 large rifle primers.  Other than switching to real black powder (trying to use what I have on hand), can anyone suggest what I should do differently to get better results?

Thanks for your thoughts!
Michael

[Trailrider]

It's been awhile since I shot Pyrodex RS, but I wonder about your crimp.  Pyrodex requires good bullet "pull" which depends on both the tightness of the case neck and the crimp.  Obviously you don't want to crimp so hard that you collapse the case, but you should be able to see the curvature of the case mouth into the crimp groove.

Another variable might be to change to magnum rifle primers.  And while Pyrodex does require a slight compression, you may want to try going to, say, 1/16" or 3/32" compression.

You should be doing better than 8-inch groups at 25 yards!  You might just need to switch to something else, like 777.

Hope this helps a bit.

[Wolfgang]

I'd personally look to the bullets and the barrel before looking to alter the load. 

What does your barrel slug ?   What are the diameters of the bullets in the factory loads and the ones you are using in your hand loads. ?   How deep is the rifling ?  If the rifling is shallow hard cast bullets may shoot fine but soft cast ones not stabalize.  Just my thoughts on what I would look for first.   

[Aggie Desperado]

With groups (or patterns  ) that large, it's likely a combination of several things.  All the above suggestions are excellent.  I think I'd particularly check bore diameter to make sure you have the correct bullet size (from exact bore diameter to 0.001" over bore diameter) cast from a soft alloy (20:1 or softer).  You might also try an overpowder wad.  I've also found I get significantly better groups with Pyrodex Select powder.  For real black powder, I like Goex Express for best accuracy.

[senormik]

Thanks for your thoughts on this.  One thing that I'm particularly curious about is why the Buffalo Arms smokeless powder rounds shot MUCH better, using the same bullets and cases?  Assuming that the bullets are properly lubed for black powder, could the simple switch between smokeless and pyrodex really make that much difference?

[Aggie Desperado]

It could.  All the items mentioned can have a major effect on accuracy with black powder.  Amount of powder compression, overpowder wad, amount of crimp, granulation of powder, Select or Express versions which are more uniform in grain size.  A combination of all these things can make a tremendous difference.

One thing that just occurs to me is: did you thoroughly clean your gun after shooting smokeless ammo and before shooting the black powder loads?  The combination of the smokeless and BP fouling makes an incredible gunk that will quickly foul the bore so that you couldn't hit a barn at 50 yards.  For cleaning BP fouling, I like a 10:1 dilution of Ballistol and water.  Folks term this "moose milk".  Don't clean BP fouling with oil based solvents and lubricants.  Ballistol or similar materials work very well instead.

[senormik]

Ah ha.  I did actually shoot some smokeless rounds just before firing the black powder rounds.  I'll be sure not to do that next time, and will try some loads of varying compression.  Thanks for the info!

[Aggie Desperado]

Let us know what happens.  I'll be curious to find out.

That happened to me the first time I loaded and shot BP ammo.  Not knowing any better, I shot my rifle with smokeless as part of load development.  I then changed and started shooting ammo loaded with BP.  After a few rounds I couldn't hit the target at 25 yards and later had to hammer a cleaning rod down the bore.  I took me quite a while to figure out what happened - it was long before I found this forum.