Musket cap blow out

deer655 · 06-08-2010, 05:36 PM

I have hunted with musket caps for years without any problem. This morning was 61 degrees here so I had an itch to go shooting. I worked up 8 speed load tubes; 4 with 260gr noslers,hph12 sabots and 100gr equiv of black mag3,, and 4 with 300gr harvester pts with 100 gr equiv of black mag. It was without a doubt the best shooting I have ever done. I was shooting 80 yards back. My first shot with the noslers was 1 inch high which I expected since I am sighted in around 100 yards. My next 3 shots were right over the first but in the same hole. I had never shot a cloverleaf pattern before. The 300 gr harvesters did almost as good;the first 2 went into the bullseye,the next 2 were an inch over this.What blew me away was that every musket cap had a small hole blown right thru the center. I had never had anything like that before. The only diference was that I had jb bore paste the barrel a month earlier but had thoroughly cleaned it out. The other difference was that I tapped my powder measure till it quit falling and then leveled it out with powder. Do you think by doing this that I was going beyond what a musket cap can handle. I would imagine that this would only add 5 to 10 gr equiv more to my loads. These were rws musket caps which are great quality. I need to learn how to load pictures as the ol mk85 was barking good today.

MountainDevil54 · 06-08-2010, 05:39 PM

pretty much normal. #11's and muskets normally explode into pieces for me.

cayugad · 06-08-2010, 05:43 PM

It could be that the extra little powder did this, but I doubt it. I would really hate to guess what was going on. Perhaps the super cleaning with the bore paste added pressures in the barrel. Or you had a bad batch of top hats. With that kind of accuracy you describe, I would not worry about it.

flounder33 · 06-08-2010, 06:05 PM

I wouldn't worry about a thing when you are shooting like that. The mk-85's rule.
Art

lemoyne · 06-08-2010, 06:52 PM

If the restrictor in your nipple is flame cut it will cause more blowback.

HEAD0001 · 06-09-2010, 09:59 AM

I have a musket cap ignition system on my MK-85 also. But to be honest I have never looked at the musket cap after firing, but it is pretty well destroyed. And for my elk load I shoot 120 grains of 3F BP with a 525 grain bullet. So as we all know that is a very very stiff load. So I do not think you are in danger.

It takes a lot to get the JB out of the bore after you lap or try to lap the barrel. You may not have gotten all of that out.

You may have a nipple problem as stated above. Just change the nipple, and give the barrel another thorough cleaning to cut any paste out, if any is left.

And by the way you are right. The MK-85 is a fantastic rifle. Tom.

deer655 · 06-09-2010, 12:59 PM

Using the bore paste almost made my barrel look new again. I've had caps unfold,splatter to a mess but had never seen a perfect cap when I got thru but each had a hole blown out the center. If its means great shooting then so be it. Best time I have had shooting in a long time.