How low can you go?

I was out doing a training session with two newbie BP shooters, using reduced loads to let them get control of the loading procedure and safety before trying anything serious. One gun a .45 that I built, the other a .50, both 36" long and both flinters. I was using 30 grains Goex 3f and PRB in both guns. We were shooting at playing cards on a 1/2" thick plywood frame at 25 yds, and doing about average, when I realized that the balls were bouncing off the target frame!

This did not just happen once, but numerous times, in both guns, with us being able to recover the balls undamaged and almost good enough to load again. The balls all showed good fabric imprint and rifleing impressions, they just didn't have enough umph to punch through the plywood. I jumped up to 60 grains and got normal performance from both guns.

60 grains is a full charge shoots to the sights load in the .45 I built so I had figured that 30 grains being a full load in my .44 C&B pistols, and plenty powerful, it should make a good half load in the long guns, WRONG! I know "half loads" are a popular way to go these days, but you can get into safty problems with a load that is too reduced.

A feller could bounce one of those balls off a tree limb and smack a knot on his head! I can see the squrrils laughing themselves silly. Would probably fall off the tree limbs amd hurt themselves.

 

[Ohio Joe]

That's interesting, and I could see where this could happen. Plywood is as we know made in layers and glued together which causes a spring effect. Shooting in high humidity as I have found out in the past seems to reduce the effectiveness of the load after a few shots. That added in with reduced loads most likely enhanced the negative effect you experienced. I perfer to use 'tar board', or 'cardboard', as it doesn't splinter and should eleminate this "bounce" effect... I expect this training session had some folks scratching their head?

 

[Stumpkiller]

60 grains is a full charge shoots to the sights load in the .45 I built so I had figured that 30 grains being a full load in my .44 C&B pistols, and plenty powerful, it should make a good half load in the long guns, WRONG! I know "half loads" are a popular way to go these days, but you can get into safety problems with a load that is too reduced.

Sumpin's happening?? 30 gr with a .45 cal, as you noted with your pistols, should be stout enough to beat the plywood. How large a vent hole do you have in those flinters?

I remember reading that Turner Kirkland did a test with a barrel he was selling (I think for the Belgian flinter he used to sell) and tapped and plugged both ends of a 12" section. He added 200 gr of powder and put a cannon fuse in the 1/8" vent and ducked for cover. The entire explosion escaped through the vent without damaging the barrel! I'm thinking something like that is happening with your light loads. They're expending a goodly portion of their energy out the vent. I up my .54 charges about 15% for 'vent loss' when going from percussion to flint.

 

[BrownBear]

Don't know diddly about flinters, so I'll doff my hat to Stumpkiller on vents. Something is definitely going on with your setup, because 30 grains behind a RB in my 54 GPR capgun pierces 3/4" plywood through and through at 50 yards, and you have to dig a bit to find the ball in the dirt behind it. It's my favorite small game load, and I shoot a whale of a lot of them at targets, too.

 

[Ohio Joe]

Stumpkiller's reply sounds pretty much on the money... I didn't think about my kids shooting their muzzleloader's, (both .45 caliber) with reduced loads, (20 grains of 3fg Goex), at a swinging 1/2 inch plywood target I made for them. They shoot at 20 yards and their ball penetrates through the plywood... In my first post I was remembering a friend of mine shooting at 100 yards with his .45 caliber rifle on a rainy humid day while I was spotting for him under the covered firing line. Through my scope I actually saw one of his .440 round ball's peter out just before it got to the target... I told him we could walk down range and I could show him exactly where his ball landed... He laughed, we walked, I showed him his .440 ball laying a little better then halfway in the mud, about ten feet from the target where it had skidded to a stop... This was from a percussion rifle no less. He obviously had an awfully fouled load...

 

This was a sunny day. temp in the mid 70s and no intense humidity. The touch hole I bored is 5/64 and the other flinter was smaller (I drilled it out since then). The only thing I can figure is that the powder was from a previously opened can left from the fall hunting season. Could have lost some of its umfh due to humidity over the winter, though I never had the problem before. It had normal recoil and power when I increased the loads and shot to point of aim. Hope I didn't have a RB stuck in the bottom of my measure or something! I did use a different measure for the full charges. Guess I better check out the shooting box for debris.

 

ghost... another thought; are you sure it was plywood and not particle board. Particle board has some very, very strong resins in it that make it pretty hard. I've worn out steel saw blades pretty quick on that stuff. Went to using carbide blades and they only fair a little better. It's like trying to saw thru glass. :shocking:

 

[Stumpkiller]

I'm at a loss. 5/64" is perfect.

I have some FFFg powder that I am ashamed to say is 10 years old (in a 3 lb coffee can - takes a while to use it up at my current .36 revolver usage). Still pops when I pull.