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In your experience how many thousands over groove diameter does your ball and patch add up to?
Grooves, ball and patch question.
- Thread starter PineyCreek
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There's really no one answer to this, only a starting point for load development.
I will be assuming a tight load that will require a short starter to load.
My starting measurement is what is the bore diameter land to land?
Next what is the depth of the groove?
Let's assume we have a bore diameter of 0.500. I would select a ball of 0.490.
Next we have a groove depth of 0.008.
So I would want a patch that compresses to 0.005 and fills the groove of 0.008. Note: Using a short starter will compress the patch far more than we can compress with either a digital caliper or by abusing a micrometer.
I would want a patch of 0.018" of cotton drill cloth from JoAnn's which would be fairly tight. So for this case the patch would be 0.005" over the available space or 0.010" over the groove depth uncompressed. As the patch is pushed into the bore the material will bunch up so compression of the patch in the groove will not be linear. And of course, lubrication matters. Use of a wet lube will allow more compression than a dry lube.
The answer would be different if I started with a 0.495" ball.
Tell us what rifle you will be shooting, what caliber, what patch material, what lubrication and for what purpose.
I will be assuming a tight load that will require a short starter to load.
My starting measurement is what is the bore diameter land to land?
Next what is the depth of the groove?
Let's assume we have a bore diameter of 0.500. I would select a ball of 0.490.
Next we have a groove depth of 0.008.
So I would want a patch that compresses to 0.005 and fills the groove of 0.008. Note: Using a short starter will compress the patch far more than we can compress with either a digital caliper or by abusing a micrometer.
I would want a patch of 0.018" of cotton drill cloth from JoAnn's which would be fairly tight. So for this case the patch would be 0.005" over the available space or 0.010" over the groove depth uncompressed. As the patch is pushed into the bore the material will bunch up so compression of the patch in the groove will not be linear. And of course, lubrication matters. Use of a wet lube will allow more compression than a dry lube.
The answer would be different if I started with a 0.495" ball.
Tell us what rifle you will be shooting, what caliber, what patch material, what lubrication and for what purpose.
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An in depth response, thank you. I am shooting a .54 cal. Lyman Deerstalker. Bore dia. is .542, groove dia. is .558. Using a .535 ball with a .012 linen patch. Lube is a mix of 75/25 bees wax and canola oil. Performance has been poor.
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I forgot to add that all I do is punch paper.
longcruise
70 Cal.
Without going into a lot of math, I'd say that your .012 patching is too thin. Have examined your fired patches? You might want to try some .015, .018 and even. 020.
Also, Lyman barrels are notorious for cutting patches when new. Smoothing the bore might be in order as well as smooth the radius at the muzzle.
Also, Lyman barrels are notorious for cutting patches when new. Smoothing the bore might be in order as well as smooth the radius at the muzzle.
Col. Batguano
75 Cal.
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Many people report it may take 100-200 rounds through a bore before it stops cutting patches and finally "smooths in". I had that issue with my FCI 38 cal. It was 200-250 rounds before I could even FIND a patch, and that was with a LOT of experimenting. It was only then that I could start getting serious about working up a decent load combo for it.
While I like linen as a patch since it holds together better than cotton, it seems that your linen may be too thin.
Lets play with my musings.
You have a 0.535 ball in a 0.542 barrel leaving 0.0035 (0.542-0.535)/2 windage to apply compression to the patch.
The groove depth is 0.008" (0.558-0.542)/2.
That gives a depth to fill of 0.0115" to fill. That's a lot of compression over the lands and none to fill the grooves. Between the gas cutting through the grooves and the compressive land cutting there is likely quite a bit of patch damage.
From a starting point for load development, a ball of 0.530" diameter nd 0.022" patch using your bee's wax and oil lube. You will have 0.006" between the ball and the lands with 0.014" to the bottom of the grooves. That will load fairly tightly and fill the grooves. Its worth a try.
Lets play with my musings.
You have a 0.535 ball in a 0.542 barrel leaving 0.0035 (0.542-0.535)/2 windage to apply compression to the patch.
The groove depth is 0.008" (0.558-0.542)/2.
That gives a depth to fill of 0.0115" to fill. That's a lot of compression over the lands and none to fill the grooves. Between the gas cutting through the grooves and the compressive land cutting there is likely quite a bit of patch damage.
From a starting point for load development, a ball of 0.530" diameter nd 0.022" patch using your bee's wax and oil lube. You will have 0.006" between the ball and the lands with 0.014" to the bottom of the grooves. That will load fairly tightly and fill the grooves. Its worth a try.
hanshi
Cannon
Well, let's see. I can give an example or two that works for me. My favorite .45 flintlock has grooves of .010" or .012", just don't know which one. When using either a .440" or .445" ball (both work) and a canvas patch, .023" compressed, and lubing with either mink oil or Hoppes BP Lube It loads with the wood rod and shoots very accurately. Fired patches could be used a second time. My .50 has .016" grooves and uses a .490" ball and the same canvas patch for excellent shooting.
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Thanks so much for your analysis. I have some .530 balls and some .020 pillow ticking.Will give it a try this next week. Thanks.
Tinhorn
40 Cal
I'm having the same problem, and my CVA Belt Pistol in .50 cal. and my Browning Mountain Rifle (.50 cal) seem to take different diameter balls. It seems to be .495" for the rifle, and .490" for the pistol. I use pillow tick (.018") from Walmart. Here's a good lube, the Machinists' favorite- 25% mineral oil in water. Best bullet lube I've ever used, dirt cheap, and if machinists use it to cool cutters on machines that cost as much as a new Cadillac, it must be OK for steel barrels.
Try some and you'll see. I'm ordering a .495" RB mold from Midway to try and cure my own blowby issue. My .490" roundballs go in the barrel with finger pressure. They must be too small. But they shoot fantastic accuracy, and destroy every patch.
Try some and you'll see. I'm ordering a .495" RB mold from Midway to try and cure my own blowby issue. My .490" roundballs go in the barrel with finger pressure. They must be too small. But they shoot fantastic accuracy, and destroy every patch.
Tinhorn, Is it blow by or are the lands cutting the patch? Is it the Browning Mountain Rifle or the CVA pistol. I think it may be time to take the edge off the lands.
First though, get a reasonable digital caliper to measure the bore. I think the CVA will have a smaller bore land to land than the Browning. In a muzzle loader caliber designations are a suggestion, not a standard with tight tolerances. I have a CVA 50 caliber Mountain Pistol that requires a 0.490 ball and my favorite 0.017 Cotton drill cloth. The Browning needs a 0.498 ball and the same patching. Both get my mix of 1 part water soluble oil to 7 parts of water.
The Browning should have a very nicely rounded crown, so the crown shouldn't be a problem. The gun with the patch shredding issue should get the land smoothing treatment. Get a 45 caliber jag and some 0000 steel wool. Run a wad of the steel wool up and down for about 100 strokes and see what happens to the patch. Clean the gun very thoroughly to get all the shavings and grit out of the barrel.
First though, get a reasonable digital caliper to measure the bore. I think the CVA will have a smaller bore land to land than the Browning. In a muzzle loader caliber designations are a suggestion, not a standard with tight tolerances. I have a CVA 50 caliber Mountain Pistol that requires a 0.490 ball and my favorite 0.017 Cotton drill cloth. The Browning needs a 0.498 ball and the same patching. Both get my mix of 1 part water soluble oil to 7 parts of water.
The Browning should have a very nicely rounded crown, so the crown shouldn't be a problem. The gun with the patch shredding issue should get the land smoothing treatment. Get a 45 caliber jag and some 0000 steel wool. Run a wad of the steel wool up and down for about 100 strokes and see what happens to the patch. Clean the gun very thoroughly to get all the shavings and grit out of the barrel.
Sidney Smith
58 Cal.
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I use the same .018 patch for my .530, as well as .535 balls. Of course the latter is tight but it still goes down. That's as far as I go. I don't get into the fine measurements.
Tinhorn
40 Cal
You folks are right, the CVA has a much tighter bore, which is OK for a belt pistol carried inverted on the belt!
I went over to a friends' house last night, and we tried his box of Speer swaged .495" RB in my rifle, and they loaded so-so with a .016 tick patch and mineral oil/water patch lube. Not real tight, but maybe tight enough. I will buy a box of swaged .495s and see how they run. HOWEVER- If I get them too tight then reloading after 25 shots or so at a Rondy will be an issue for sure. So I need to balance patch performance and fouled barrel loading for the best from-the-pouch trailwalk success. As for the pistol, I may just play with patch thickness, and use the same ball, if I can. Thanks for the help, this has been an issue with this heavy offhand Browning I use for paper punching. I have a rifle bag, and a smaller pistol bag for trailwalk, so different ball, powder, etc is no issue. Tinhorn
I went over to a friends' house last night, and we tried his box of Speer swaged .495" RB in my rifle, and they loaded so-so with a .016 tick patch and mineral oil/water patch lube. Not real tight, but maybe tight enough. I will buy a box of swaged .495s and see how they run. HOWEVER- If I get them too tight then reloading after 25 shots or so at a Rondy will be an issue for sure. So I need to balance patch performance and fouled barrel loading for the best from-the-pouch trailwalk success. As for the pistol, I may just play with patch thickness, and use the same ball, if I can. Thanks for the help, this has been an issue with this heavy offhand Browning I use for paper punching. I have a rifle bag, and a smaller pistol bag for trailwalk, so different ball, powder, etc is no issue. Tinhorn
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Tinhorn,
first of all, if your patches are being destroyed, you are NOT getting your best accuracy. Second, with a proper Tight patch, ball, lube combo, your 25th shot should load as well as your first.
A loose load will produce more fouling than a tight one. A tight load cleans the barrel every time you load it.
first of all, if your patches are being destroyed, you are NOT getting your best accuracy. Second, with a proper Tight patch, ball, lube combo, your 25th shot should load as well as your first.
A loose load will produce more fouling than a tight one. A tight load cleans the barrel every time you load it.
It is not a failure on your part to wipe your bore as the barrel fouls. There is no requirement to fire 25 shots at a Rendezvous without wiping the bore.
I know many people who shoot Wood Walks and Rendezvous who wipe the bore to keep loading easy. One of the better competitors at Woods Walks will run a cleaning patch down the bore between stations to keep fouling under control and accuracy to best performance. I will wipe the bore even though I am not one of the top competitors.
I know many people who shoot Wood Walks and Rendezvous who wipe the bore to keep loading easy. One of the better competitors at Woods Walks will run a cleaning patch down the bore between stations to keep fouling under control and accuracy to best performance. I will wipe the bore even though I am not one of the top competitors.
Tinhorn
40 Cal
Got out today, Memorial Day, and busted caps. My rifle had issues, but loved the .495 ball. I slugged the barrel for about 2" down the muzzle, and got .516" in the grooves, and .508 or so on the lands. But pillowtick and .495s loaded great, and hit claybirds laying on the ground at 40 paces, if I held steady. My barrel was wobbly in the stock, ( I have no idea why walnut from Browning would shrink and warp after 35 years.....) and showed a distinct lack of DuckTape. So after .017" of tape at the breech, and .008" behind the nose cap, I could hit half a claybird at 40 paces offhand. With the wobbly barrel, I missed by 4 inches or so. So I'm a happy kid. Cheers!
Tinhorn
40 Cal
DIFFERENT SUBJECT- To all Amigos at the Campfire..... I just got off the Chat feature of MIDWAY USA, and the lady said that once you place an order, it's done, No Changes at all! So they have my wrong credit card info in their database, and I offered to help her change it, and she declined. She said "Wait until the order is Declined for Payment, and re-order from us." And I learned their PH# goes nowhere, and they don't answer it anymore.
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