Wild inaccuracy with CVA .50

Muzzleloading Forum

Help Support Muzzleloading Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I had my flintlock start throwing wild shots, and told myself I hadn't changed anything. Then I realised I had been using biggish patches and folding them over the ball to reduce bruising with the short starter. That meant they were not letting the balls fly free of the patch at the muzzle!
Consistency with components and how you load them will always be your friend.
 
Well I have tried several more things.
Weighed all balls and removed outliers from 3 standard deviations.
Rattled the balls in a bottle with water and detergent to obliterate sprue lines.
Bought an endoscope and took pictures down the bore, but it wont focus on the rifling. Darn it!

Recovered patches from experiments.
All patches were measured with micrometer, generally 0.016" on the ratchet and .011"-0.013" compressed.

Tried Dutch Schultz dried lubed patches (20% soluble oil plus a drop of detergent in water, dried in sun beforehand);
tried beeswax/olive oil grease;
tried Ballistol 20% in water

1: duck fabric: recovered patches were shredded.
upload_2020-2-22_14-2-13.png


2: New 'ticking' looks like calico with ticking inked pattern - shredded
upload_2020-2-22_13-57-42.png

So I went back to my yellow hi-vis workshirt, which has much denser weave.
2 groups of patches: upper, soaked with 20% Ballistol, over polenta and a 55gn charge PPP black powder (Similar to FFF but narrower size range).
Lower group, same patch, lube and filler but 69gn PPP, increasing charge to get faster spin and I hoped more stability.
1&2 patches -polenta-milk-55gPPP_&_69gPPP.JPG

Groups from these shots were group 1 marked blue, group 2 marked orange. 50 m on standard pistol target, 8" dia black.
Please note that as I shot these 12 shots there was increasing tightness of fouling about 8" up the barrel.
The wilder shots were later in the strings. In the past a good wet patch or a wet patch above the rammer meant no increase in tightness over up to 45 shots.
I believe this thickening fouling comes from using PPP instead of PP, which did not give this problem but powder is hard to get here.

1&2 -polenta-milk-55gPPP_then_69gPPP.JPG

The groups, 8" off a benchrest at 50m using a familiar rifle, are appalling. I expect to see 4" or better if I do it right, as I do 1.5" with a .22.


1&2 patches -polenta-milk-55gPPP_&_69gPPP.JPG
1&2 -polenta-milk-55gPPP_then_69gPPP.JPG

Finally I did the same 55+filler+Ballistol but cleaning between shots. There was heavy fouling removed each time, but now there was no feeling of constriction at 8" above the charge.

Patches are much better, but group size the same.

3-polenta-milk-cleanbetweenshots.JPG

4-polenta-milk-cleanbetweenshots.JPG


CONCLUSION: Nothing gave markedly better groups!
 
Last edited:
Next actions: I ordered pre-cut patches from a distant BP dealer. I didn't question closely on price and I am now out $60 plus pp for four bags of 100 patches!
 
Last edited:
Do you wash your patch material ?

Is your bore rusty ? pitted?

No, the new materials were not washed. However the hi-vis shirt was well secondhand so many times washed!
The endoscope was to get a look at the bore. I suspect pitting further down, but cleaning between shots it wasn't grabbing. I have been shooting this rifle maybe 10 years, and never got a good look at depth in the bore.
 
Did it use to shoot good? I have had a time frame about 3-4 years ago where I couldn't shoot a group with my fav CVA. NOTHING worked. Nothing changed and suddenly one day I shot my 2" group at 90 yds and it still shoots??? Weird stuff. Dont give up. Can you group with other rifles? Is it YOU?
 
No, the new materials were not washed. However the hi-vis shirt was well secondhand so many times washed!
The endoscope was to get a look at the bore. I suspect pitting further down, but cleaning between shots it wasn't grabbing. I have been shooting this rifle maybe 10 years, and never got a good look at depth in the bore.

I've never needed an endoscope to tell if the bore was pitted, I can feel it on my ramrod. That's one of the reasons I use a wooden rod, better sensitivity. Another way to tell is to run a light cleaning patch on a jag up and down the bore. I use fruit of the loom T-shirt material. If the bore is rough the cleaning patch will snag or tear.

New shooting patch material has a loose weave and sizing in it, washing and drying removes the sizing and tightens the weave. New material with sizing has a tendency to burn through and shred.

I do all my testing at 25 yards first, it's easier to get a good sight picture at that distance and eliminate the human variable.

Like Britt said your barrel may need lapping or polishing if the lands are just sharp, but the patches look more like pitting to me.

What is your patch thickness ?
Most CV's like between .010 and .015 thick

What powder are you using ?

Lastly, I notice your white colored patches turn green. what's making them aqua green ?
 
Did it use to shoot good? I have had a time frame about 3-4 years ago where I couldn't shoot a group with my fav CVA. NOTHING worked. Nothing changed and suddenly one day I shot my 2" group at 90 yds and it still shoots??? Weird stuff. Dont give up. Can you group with other rifles? Is it YOU?

I had the same thing happen, I forgot how to shoot it.
 
What is your patch thickness ?
Most CV's like between .010 and .015 thick

What powder are you using ?

Lastly, I notice your white colored patches turn green. what's making them aqua green ?

Yep. I use the micrometer, and .013 to .016 is where they fall before I choose to try them.
Powder is now WANO PPP, which I have used for years but had recently used 2 cans of Pyrodex. However from memory the rifle seemed to work better with PP than PPP - less fouling. I am going into the Nationals at Easter and Pyrodex is not acceptable.

As for the 'white patches turning green', I think my photo order has misled. The white with grey stripes are only shown in one pic, unfired, beside a duck unfired patch that was dark green. The subsequent pics are all patches that were originally yellow work shirt.
 
How do scotch brite green/maroon scratch pads do with polishing a bore, compared to fine steel wool?
Could you possibly post a closeup photograph of your barrel crown?
I have been very annoyed to find I cant hit a bull in the bum with my CVA, since the old ticking I used for patches ran out.
Did the accuracy go away from one shot to the next? Or did it occur at the start of a new shooting session? Is it possible you didn’t clean the bore properly between sessions? The patch material change can impact accuracy, but if it’s only somewhat close to the old ticking you should see such large groups. Based on the photographs of your patches it sure appears to be a rough (very rough) bore or crown. CVAs with a smooth bore and crown tend to be easy to get shooting well.
 
How do scotch brite green/maroon scratch pads do with polishing a bore, compared to fine steel wool?
Steel wool is usually made of a low carbon steel which makes it about the same hardness as the steel your muzzleloading barrel is made from. Since it is the same hardness, it doesn't exactly cut away material in the common sense but it wears away sharp edges like the ones found on new rifling.
It takes a lot of work to remove much but I've found that 20 to 30 minutes of pumping a jag covered with steel wool while changing the steel wool about every 5 minutes is enough to dull up the rifling grooves so that they won't cut a good cloth patch when it is loaded or fired.

Scotch Brite pads on the other hand are coated with hard abrasives (Aluminum Oxide or Titanium Dioxide) that will cut away the steel the barrel is made from. Think of it as a very fine sandpaper.

The sandpaper grits for Scotch Brite pads are:
Tan # 7440 = 160 grit
Maroon # 8447 = 380 grit
Green # 74 = 600 grit
Gray # 7448 = 800 grit
White #7445 = 1200 grit

Which one to use is up to you but generally speaking 160 grit will remove metal fairly quickly. 380 grit takes a lot of work to remove much metal. 600 grit is more of a rough polishing grade on metal. 800 and 1200 grit are closer to polishes.
 
Well I have tried several more things.
Weighed all balls and removed outliers from 3 standard deviations.
Rattled the balls in a bottle with water and detergent to obliterate sprue lines.
Bought an endoscope and took pictures down the bore, but it wont focus on the rifling. Darn it!

Recovered patches from experiments.
All patches were measured with micrometer, generally 0.016" on the ratchet and .011"-0.013" compressed.

Tried Dutch Schultz dried lubed patches (20% soluble oil plus a drop of detergent in water, dried in sun beforehand);
tried beeswax/olive oil grease;
tried Ballistol 20% in water

1: duck fabric: recovered patches were shredded.
View attachment 24695

2: New 'ticking' looks like calico with ticking inked pattern - shredded
View attachment 24694
So I went back to my yellow hi-vis workshirt, which has much denser weave.
2 groups of patches: upper, soaked with 20% Ballistol, over polenta and a 55gn charge PPP black powder (Similar to FFF but narrower size range).
Lower group, same patch, lube and filler but 69gn PPP, increasing charge to get faster spin and I hoped more stability.
View attachment 24689
Groups from these shots were group 1 marked blue, group 2 marked orange. 50 m on standard pistol target, 8" dia black.
Please note that as I shot these 12 shots there was increasing tightness of fouling about 8" up the barrel.
The wilder shots were later in the strings. In the past a good wet patch or a wet patch above the rammer meant no increase in tightness over up to 45 shots.
I believe this thickening fouling comes from using PPP instead of PP, which did not give this problem but powder is hard to get here.

View attachment 24690
The groups, 8" off a benchrest at 50m using a familiar rifle, are appalling. I expect to see 4" or better if I do it right, as I do 1.5" with a .22.


View attachment 24689View attachment 24690
Finally I did the same 55+filler+Ballistol but cleaning between shots. There was heavy fouling removed each time, but now there was no feeling of constriction at 8" above the charge.

Patches are much better, but group size the same.

View attachment 24691
View attachment 24692

CONCLUSION: Nothing gave markedly better groups!

Hi ChrisPer. I kinda went down that same road with accuracy problems in a Lyman deerstalker. It was my patch lube that was given me the trouble. It's the last thing I thought of. Now I have a setup of six different lubes applied To precut patches. Everything from hand cleaner to MAP. My groups went from 8 to 10 inches to 3 inches with nothing more than a change of patch lube. Does that make sense? I don't really know but it worked for me. All of the lubes I used were all with bought en .018 pillow ticking cut patches. The same powder charge and the same round balls. I tried to eliminate all other variables except for the lube. Now I'm just waiting for good weather to test my new percussion traditions 50 caliber. It's pointless to tell you what's one worked the best for me, if anyone wants to know I will certainly pass it on, but there's a good chance it might be different for you. It was one I ordered from Tennessee. It looked just the same as other ones I have tried, so I know that this does affect some things.
Squint
 
Hi ChrisPer. I kinda went down that same road with accuracy problems in a Lyman deerstalker. It was my patch lube that was given me the trouble. It's the last thing I thought of. Now I have a setup of six different lubes applied To precut patches. Everything from hand cleaner to MAP. My groups went from 8 to 10 inches to 3 inches with nothing more than a change of patch lube. Does that make sense? I don't really know but it worked for me. ...
Great info thanks Howard! I am not that confident in my lube - I was using soluble oil and detergent in water, and then Ballistol in water. Minie grease was no improvement. The water is great for softening fouling and in the past I was able to keep shooting several cards of 13 shots without cleaning. I also tie that to using PP instead of PPP (similar to FFg vs FFFg).
On this note I will try a much higher ration of Ballistol, maybe 65% instead of 20%.
 
Did the accuracy go away from one shot to the next? Or did it occur at the start of a new shooting session? Is it possible you didn’t clean the bore properly between sessions? The patch material change can impact accuracy, but if it’s only somewhat close to the old ticking you should see such large groups. Based on the photographs of your patches it sure appears to be a rough (very rough) bore or crown. CVAs with a smooth bore and crown tend to be easy to get shooting well.
Good questions!
-I suspect I did not notice accuracy getting worse until real outliers came up, because I am shooting many different guns in different matches and had not benched this rifle for a few years. Perception is potentially clouded.
- Here are some grabs from my endoscope down the barrel. The thing seems to focus just beyond the brightness of the light, unless there is auttplug in front of it. I would go back and take better shots but I am away at work so these were my first experiments with the endoscope.

In this shot we see a fairly crisp image where the rifling meets the plug, but it isn't sharp enough to see what the brown speckle is, if pits or oxide staining or what.
upload_2020-2-24_11-41-46.png

The muzzle - could be a better focused shot
upload_2020-2-24_11-57-57.png

Rifling came fairly focuses 6" down from the muzzle due to external light
upload_2020-2-24_11-59-7.png

A ways up from the breech
upload_2020-2-24_12-0-36.png
 
You might to see if you can get a 45 degree mirror for the end of your endoscope, or invest $50 in a real borescope :
Amazon Teslong Rifle Bore Scope, 0.2inch Gun Barrel Borescope Camera with Side-View Mirror and Semi-Rigid Cable, for Windows, Mac and Android Smartphone
by Teslong
 
Back
Top