BLOWN PATCHES

[leanin chair]

Trying to come up with a recipe for "Over-The_Log" and having problems with blown patches. Using pillow ticking with teflon as I've used before but end up with flyers. I've scrubbed the barrel out real good with Brownells J-B so I know the bore is nice and smooth. Tried both 3F and 2F with better results with 2F, but still getting some blown patches. Anyone else have this problem?

 

leanin chair,

I had a similar problem with traditions pre-cut lubed patches. They alwats looked like a burnt doughnut, and printed too widely on my targets. I went with some 100% cotton flannel P.J. material and Hoppes #9 lube and bore solvent cleaned the problem up tightened my groups. I was just experimenting with what I could get my hands on.
James Taylor

 

[paulvallandigham]

What caliber? What powder charge? What size ball are you using for the bore diameter of your gun? Chunk gun shooters tend to shoot heavy charges. You are going to burn patches unless you use a filler or OP Wad between the powder and the PRB. YOu don't tell us what thickness of patch material you are using? Teflon is wonderful, but if the patching is too thin to fill the grooves, gas is going to get by and tear and burn the patching. So, tell us what groove diameter your barrel has?

 

[roundball]

A spare lubed patch (or an oxyoke prelubed wad) over the powder before seating the PRB will fix the problem.

If thats too cumbersome for an over-the-log situation, get a tighter weave patch material and/or use liberal coatings of something like Natural Lube 1000 or Hoppes No9 BP PLUS as a patch lube.

 

[leanin chair]

40 cal. rifle. .395 balls. 85 grains 2 F. .015 teflon paatching.

 

[paulvallandigham]

What lube are you using on the patching? Teflon is a surface supplement, not a SUBSTITUTE for lube.

That is a very hot load you are using. 60 grains should get you well over 1900 fps. That 90 grain ball is only going 60 yards, friend! YOur barrel would have to be 59 inches long to efficiently burn that 85 grain powder charge.

 

[rabbit03]

I would go to .400 sized balls and or 20 - 23 thousands teflon patching. Remember, not all teflon patching is the same.

When we shoot competition (which is what your fixin to do) we use the teflon patching from Texas Patching.

Unless your bore has some rough edges in it from being new, then I would suspect that this will work for you and fix your problem.

rabbit03

 

[rabbit03]

Sorry Paul, but teflon patching is a substitute for lube!

rabbit03

 

[paulvallandigham]

Not with the people I know who use it. Spit, water, or some liquid lube is used to dampen the patch, and the teflon side is place out so it contact the bore. I suspect that the dampening helps the fabric flex( stretch?) under the tight diameter balls being used.I would recommend this guy try .395, and even .400" ball in his .40 caliber rifle, as these are some of the dimensions of balls being used in the chunk gun shoots. Its takes a good whack with a mallet to seat the PRB, and only the teflon coated patching will take that blow without tearing, but once the ball is re-shapened into an oval, it goes down the barrel fairly easily, particularly in a choked barrel.

 

[longcruise]

40 cal. rifle. .395 balls. 85 grains 2 F. .015 teflon paatching.

Even knowing that, it's a bit tough to determine what kind of patch/ball fit you are getting, since not all bores are exactly what the maker says they are. Could be tighter or looser. I don't shoot a .40 but would consider 85 grains to be pretty heavy. Feel like I'm shooting a big load when using 60 3f in my .45.

But, that said, If the barrel condition is good and the patch is tough and a tight fit, you can probably get away with that load. I'd look first to the quality of the patch material and maybe try something thicker and/or tougher. Also, regardless of how carefully you lap your bore, the crown can wreck your patch before you ever push it down the barrel if it's not "right". If it takes a lot of effort to start the ball but then it goes down fairly easily in a clean barrel, the crown is probably not "right" and may be damaging your patch when you start the ball. Lighter loads may not finish the job of tearing the patch up but the heavier loads will.

I see a lot of guys saying that their gun shoots great until they get to xx grains of powder and then their groups go to heck. Often xx is not a very heavy charge at all. I suspect that in many of those cases the crown is damaging the patch upon starting the ball and while it shoots ok with the light charges, the heavier ones that should be just fine with an undamaged patch will "blow out" or "burn out" a damaged patch.

 

[rabbit03]

Did you get my private message yesterday?

Bonnie will send you some free samples of what she has and it will cure your problem.

rabbit03

 

[rabbit03]

Not with the people I know who use it. Spit, water, or some liquid lube is used to dampen the patch, and the teflon side is place out so it contact the bore. I suspect that the dampening helps the fabric flex( stretch?) under the tight diameter balls being used.I would recommend this guy try .395, and even .400" ball in his .40 caliber rifle, as these are some of the dimensions of balls being used in the chunk gun shoots. Its takes a good whack with a mallet to seat the PRB, and only the teflon coated patching will take that blow without tearing, but once the ball is re-shapened into an oval, it goes down the barrel fairly easily, particularly in a choked barrel.

Well Paul, old habbits die hard perhaps and the need to wet a patch might be one of them. However it is not necessary. The folks I shoot with as a rule don't use any wetting agents and their results speak for themselves.

But we are also on the same sheet of music for this fellow about the ball size as I had already stated. And he really needs a tight patched combo for the kind of accuracy he is wanting. Minute of deer aint a gonna get it at one of these over the log matches.

rabbit03

 

[paulvallandigham]

Rabbit: I will pass on your advice on dampening the patches. I suspect that most people should be checking the crowns on their barrels. Its fairly easy to eliminate this as a cause for torn patches. Just take a strip of patching, leaving enough on both sides of the barrel to allow your fingers to take a firm grip, and seat a ball in the barrel with your short starter, centering the ball in the middle of the strip. Then, grab the two ends firmly in your fingers and pull the ball back out of the barrel. Now, examine the strip of cloth. If it has holes in it, those HOLES were cut by the front of the lands, and that needs to be changed to eliminate the tearing. If no holes appear, then the holes are being caused by either burrs, or the wrong thickness of patching for the depth of the grooves, and too hot a load.

We are in deed on the same page. :thumbsup:

 

[nchawkeye]

That's just too dang much powder in a .40, drop down to 40-50grs FFF...I use 25 for squirrels, shoots flat out to about 50 yards...

I'd also go to WalMart, buy their pillow ticking, make up some of Stumpy's lube and try again...