Roundball accuracy

[bigted]

Been pondering this for a long time ... along with you all.

Wonder if I have come up with a fairly good theory.

I along with others can get 2 shots that almost touch at say 45 yards. Then the 3rd shot goes its own way ... even off a bench rest. I get open groups with 3 shots of around4 to 6 inch at 40ish yards consistantly. Tight patched .595 , .600 ball over the powder and wad over the top, powder charges from 60 grains 3F to 90 grains and 70 grains 2F up to 100 grains. Wads between powder and ball as well as ball right down on the powder. Nothing changes much between any combo.

My theory is such. Might it be barrel flex what with the thin long round portion of the barrel. Might the heat of the thin barrel begin throwing balls in a very short time ... say within 2 shots?

I wonder if a pretty rigid heavy barrel would give better accuracy with the smooth bore. Say a 1.125 inch breech diameter tapered to a 1 inch at the Muzzle. Maybe even heavier barrels or shorter more rigid barrels.

There is my spewage. My fevered wonderings have now been released. What say yee? Am I batty as a loon or do ya think my pondering has any merit?

Ted

 

[oldwood]

Have you slotted your barrel pinning loops. ??? The slotting keeps the barrel heat from torking the barrel . I've seen enough of this , that I just routinely slot all my barrel pin loops.

 

[bigted]

No have not slotted them. First I heard of that was Jim Kibler in one of his videos. Does it make a big difference? Makes perfect sense for it to effect a barrel. Guess I need to slot em and see if it does the trick. Might just act like a free floated modern rifle I would guess.

Ted

 

[LME]

All I know is riflings were invented to improve accuracy?

 

[NorthFork]

I've never slotted my barrel trunnions and yet I kill 3-6. deer a year with 0, and I said ZERO misses

 

[Buckskinquin]

Try seating your PRB with a moist patch. Takes a bit more time, but you assure your barrel is pretty close to the same condition as the previous shot. You’ll also be surprised how much fouling you pull out. I use both sides of the patch doing this on successive shots.

 

[bigted]

I've never slotted my barrel trunnions and yet I kill 3-6. deer a year with 0, and I said ZERO misses

I just went out and looked. Yes the trunions are slotted.

Can I ask you your normal range and load?

 

[bigted]

Try seating your PRB with a moist patch. Takes a bit more time, but you assure your barrel is pretty close to the same condition as the previous shot. You’ll also be surprised how much fouling you pull out. I use both sides of the patch doing this on successive shots.

I will try this also. Never thought about swabbing AFTER loading. I have not swabbed between shots with this smoothbore either. With the lubed patch of .018 wrapped round the .595 ball. Loads easy everytime so never thought of running a spit patch over the load.

Thanks, Ted

 

[NorthFork]

I just went out and looked. Yes the trunions are slotted.

Can I ask you your normal range and load?

Multiple rifles/smoothbores, both factory and custom. .45", 50", 63" and .72". Yes I said .63", not .62". From point blank to 125 yards. Load does vary obviously. For the common 50cal, I use a .015" TOTW mink tallow lubed patch and a .490" ball (actual cast size is .493"),and 80- to 100 grains of ffg real black powder. If you asked about a particular rifle I could be more specific.

 

[bigted]

Very interesting. Guess I would inquire about the 63 cal. Never ever imagined trying a 125 yard shot with my smoothbores. Bout all I can get so far is 4 to 6 inch at just this side of 50 yards. Tried a 100 pace shot once and never scratched paper with my .62.

 

[NorthFork]

Very interesting. Guess I would inquire about the 63 cal. Never ever imagined trying a 125 yard shot with my smoothbores. Bout all I can get so far is 4 to 6 inch at just this side of 50 yards. Tried a 100 pace shot once and never scratched paper with my .62.

My .63" smoothbore mikes at an actual .635" It is good to 75 yards on deer. I use 115 grains of Goex ffg then a bare ball measuring .613" actual diameter + a nitro card over top the bare ball to hold it in place for hunting. I don't trust a wool blanket wad or paper over shot card to do the same. 3-4" CTC 5 shot group at 75 yards.

 

[tenngun]

Dualist 54 has a vid shooting military cartridge in a 20 bore. He is deadly at 50 yards, gets three hits at a hundred and all misses at one twenty five. But all would have been too close for comfort if I was the target.
His target was a soldier drawing

 

[NorthFork]

Dualist 54 has a vid shooting military cartridge in a 20 bore. He is deadly at 50 yards, gets three hits at a hundred and all misses at one twenty five. But all would have been too close for comfort if I was the target.
His target was a soldier drawing

It's actually a reduced from life life size target. About 3/4.

 

[Brokennock]

My Early Virginia smoothrifle has a barrel that isn't all that thin. Not as thin as my Fusil des Chase anyway.
Either gun gets shot from the bench for load development testing. And, I wait quite a long time between shots to allow the barrel to cool.
So maybe the theory isn't too far off, if one isn't waiting for the barrel to cool.
However, at 50 yards my good load combinations don't have that much spread, and sometimes it is the 1st shot that is the outlier. And, I do see a big difference in load combinations at that distance.

 

[hep]

Been pondering this for a long time ... along with you all.

Wonder if I have come up with a fairly good theory.

I along with others can get 2 shots that almost touch at say 45 yards. Then the 3rd shot goes its own way ... even off a bench rest. I get open groups with 3 shots of around4 to 6 inch at 40ish yards consistantly. Tight patched .595 , .600 ball over the powder and wad over the top, powder charges from 60 grains 3F to 90 grains and 70 grains 2F up to 100 grains. Wads between powder and ball as well as ball right down on the powder. Nothing changes much between any combo.

My theory is such. Might it be barrel flex what with the thin long round portion of the barrel. Might the heat of the thin barrel begin throwing balls in a very short time ... say within 2 shots?

I wonder if a pretty rigid heavy barrel would give better accuracy with the smooth bore. Say a 1.125 inch breech diameter tapered to a 1 inch at the Muzzle. Maybe even heavier barrels or shorter more rigid barrels.

There is my spewage. My fevered wonderings have now been released. What say yee? Am I batty as a loon or do ya think my pondering has any merit?

Ted

i built nw trade guns for the green river forge in the 70's we used 30" sharon barrel 62cal. most popular load 60grains 2f .600 round ball and 10thou. patch. the guns we built were shipped all over the world and won shoots every where. sharon barrles are very stiff and stout. i believe that short stiff barrels is the way to go if you want accuracy. this just my opinion and you know what they say about opinions.

 

[Uncle Miltie]

Three shots is not adequate for working up a load. Groups should be 5 or10 shots to be effective.

 

[Brokennock]

Three shots is not adequate for working up a load. Groups should be 5 or10 shots to be effective.

Agreed. And even at a good 5 or 6 shot group,,, it needs repeating. I've had good groups at 50 yards with a load at the end of a shooting session, and when I come back another day and test that load again,,, they aren't as good.

 

[flintlock lover.]

Been pondering this for a long time ... along with you all.

Wonder if I have come up with a fairly good theory.

I along with others can get 2 shots that almost touch at say 45 yards. Then the 3rd shot goes its own way ... even off a bench rest. I get open groups with 3 shots of around4 to 6 inch at 40ish yards consistantly. Tight patched .595 , .600 ball over the powder and wad over the top, powder charges from 60 grains 3F to 90 grains and 70 grains 2F up to 100 grains. Wads between powder and ball as well as ball right down on the powder. Nothing changes much between any combo.

My theory is such. Might it be barrel flex what with the thin long round portion of the barrel. Might the heat of the thin barrel begin throwing balls in a very short time ... say within 2 shots?

I wonder if a pretty rigid heavy barrel would give better accuracy with the smooth bore. Say a 1.125 inch breech diameter tapered to a 1 inch at the Muzzle. Maybe even heavier barrels or shorter more rigid barrels.

There is my spewage. My fevered wonderings have now been released. What say yee? Am I batty as a loon or do ya think my pondering has any merit?

Ted

You could control barrel heat by setting a wait time between shots. Of course, this might introduce other variables such as fouling response to humidity ( saturation ), fouling hardness, shooter fatigue, ect...
Barrel rigidity's an interesting thought and maybe a thicker barrel might have an effect.
If nothing else it would slow down the tendency for you to have heat waver over the barrel while sighting. That a problem for me when shooting my large caliber (75 cal) smooth guns. I deal with this by having a bucket of water to dip the tip of the barrel in between shots.
I've found that for me, a fairly tight ball and patch combo over a tight shotgun was gives the best results with my thin walled barrel guns.
Picture below is of a 3D deer shot with a 75 cal Brown Bess @ 91 yards

 

[georgej72]

Been pondering this for a long time ... along with you all.

Wonder if I have come up with a fairly good theory.

I along with others can get 2 shots that almost touch at say 45 yards. Then the 3rd shot goes its own way ... even off a bench rest. I get open groups with 3 shots of around4 to 6 inch at 40ish yards consistantly. Tight patched .595 , .600 ball over the powder and wad over the top, powder charges from 60 grains 3F to 90 grains and 70 grains 2F up to 100 grains. Wads between powder and ball as well as ball right down on the powder. Nothing changes much between any combo.

My theory is such. Might it be barrel flex what with the thin long round portion of the barrel. Might the heat of the thin barrel begin throwing balls in a very short time ... say within 2 shots?

I wonder if a pretty rigid heavy barrel would give better accuracy with the smooth bore. Say a 1.125 inch breech diameter tapered to a 1 inch at the Muzzle. Maybe even heavier barrels or shorter more rigid barrels.

There is my spewage. My fevered wonderings have now been released. What say yee? Am I batty as a loon or do ya think my pondering has any merit?

Ted

Ted,
I ran into this problem a few years ago with my in-line. I could hit No more than three shots on paper at 100 yards. Spoke to a buddy of mine who is an avid bp guy and he advised that I swab my barrel after every other shot. I tried that and can now consistently hit 6” groupings at 100 yards. My barrel is riffled so there are differences but the concept is still the same; remove the powder fouling so that the bullet has a clean surface to travel down. Good Luck!
Jeff

 

[Comfortably_Numb]

you're having a fouling problem. Probably need more lube or a different lube.