Roundball and patching question please? Patches releasing?

[bgf]

Many thanks to all for the shared knowledge.
I got by JoAnn fabrics yesterday and bought cloth for heavier patching.
The warnings here were indeed correct - I only found four bolts out of 20 that were straight 100% cotton. All others had varying degrees of synthetic in them. Many bolts omit the fabric weight.
I bought some 11.5 oz blue denim, and two variations of "bull denim" that had no weight shown but were very close to the 11.5 but slightly thinner. I am guessing this is the 10 oz. It came in white and tan with slight variation in texture.
I washed it all last night, and plan to cut some sample patches tonight.
Thanks again, and best wishes, Marc

I found the bolt end of my bull denim, and it is 10 oz.  It is a bit over .020", probably about Daryl's .0225" after washing in HOT water.  I can only measure approximately right now and by comparison with known .020 patches.  That said, my barrels are GM and have slightly reduced rifling depth compared to your rice (?).  Assuming the holes are not from wire edge on new rifling, the 11.5 oz might be a better fit.  Either way, you are on the right track!  Keep looking at patches after you shoot, as intact patches are the best sign you have a good combination.  If reducing the charge changes the patches significantly for the better, the patch is marginal and will fail either with higher charges or under some conditions.

[Daryl]

Many thanks to all for the shared knowledge.
I got by JoAnn fabrics yesterday and bought cloth for heavier patching.
The warnings here were indeed correct - I only found four bolts out of 20 that were straight 100% cotton. All others had varying degrees of synthetic in them. Many bolts omit the fabric weight.
I bought some 11.5 oz blue denim, and two variations of "bull denim" that had no weight shown but were very close to the 11.5 but slightly thinner. I am guessing this is the 10 oz. It came in white and tan with slight variation in texture.
I washed it all last night, and plan to cut some sample patches tonight.
Thanks again, and best wishes, Marc

I found the bolt end of my bull denim, and it is 10 oz.  It is a bit over .020", probably about Daryl's .0225" after washing in HOT water.  I can only measure approximately right now and by comparison with known .020 patches.  That said, my barrels are GM and have slightly reduced rifling depth compared to your rice (?).  Assuming the holes are not from wire edge on new rifling, the 11.5 oz might be a better fit.  Either way, you are on the right track!  Keep looking at patches after you shoot, as intact patches are the best sign you have a good combination.  If reducing the charge changes the patches significantly for the better, the patch is marginal and will fail either with higher charges or under some conditions.

Spot-On = bgf!!!!  Perfect bullseye.

If I cannot re-use the patch for at least one more shot or even 4 shots with the lighter loads that cause less fraying at the edge (from muzzle blast) - the patches lack integrity - too thin or not strong enough.

My new calipers read the 10 ounce denim as - .021 one way and .0225 the other - the tines squeezed together over the fabric as hard as I can with forefinger and thumb.  I try to orient the material exactly the same each time I load but perhaps is not a big deal unless group shooting.

The 8 ounce runs .0185" and .0195".

The calipers are sold by Hornady at Wholesale Sports  ($35.94) and feel just like many high quality calipers, Mitytoyou or Sterrets - & maintain 0 which is nice. For the price, they are VERY impressive. Time will tell.

[Dphariss]

Use a pretty damp patch using both sides then a dry patch both sides. This should cure the fouling problem. As the patch runs down the bore is puts water on the surface and the patch gets drier as it goes down the bore. Experiment to find the right wetness. Many store bought patches do not work as well as diaper flannel from the fabric store.

I would use 80-90 gr of powder. Often more powder will reduce blown patches.
I would go to a .495 and a thicker patch.
Many people cutting round bottom grooves are cutting them far too deep IMO. Square grooves need only be .008-.010. They seem to cut round grooves for looks. You can also try putting a patch over the powder behind the patched ball.
Patches will not stay on a ball in flight unless glued on.

Dan

[Marcruger]

Thanks Dan,

I have shifted to the .495 roundball, and thicker patching. 

This week I bought JoAnn fabric 10 and 11 oz denim, cut patches, and lubed them. 

Rain today, so no range time. We need the rain though. 

Best wishes,     Marc