Patch not confetti-ing. Help!

[303Guy]

What the heck is going on?

http://i388.photobucket.com/albums/oo327/303Guy/RIVITINGDEEPSEATED1822205208WGSMALL1.jpg

The previous shots with the same powder charge and boolit weight all worked fine. The one above decides to be different. But why?

Here's the previous one.

http://i388.photobucket.com/albums/oo327/303Guy/181gr2205Dacron208grseateddeep6.jpg

There was a tail ring of the patch still attached to the boolit which indicates the sides of the patch disintegrated just fine. In fact, that one had Dacron filler as opposed to wheat germ for the intact patch which of course means the pressure was way lower. But the others that worked also had wheat germ filler.

[geargnasher]

Is you test tube disrupting the muzzle blast enough to prevent patch shucking?

Gear

[6.5 mike]

Think Gear may be right. Can you take it somewhere & fire a couple rns to check for patch fragments in the air or on the ground ? Do seem to remember you insert the muzzle into your tube. :Fire:

[303Guy]

Yes, the muzzle gets stuck into the device. But if that were the case I would expect most of them to do that but they don't. I should mention that the filler (wheat germ - which I'm beginning to like) was fairly well compacted under the boolit. It's pretty springy stuff that wheat germ and it leaves the bore squeaky clean and so far no rings left in the case. That could mean there was no muzzle blast acting on the boolit to blow the patch off. But why only the one? Could it be that this one was tight in the bore and up against the rifling so there was no shearing on the driving edge to cut the patch? If so then we have a new perspective on how a patch actually behaves in the bore. There was a lot of filler - like 60% of the case volume. That would make a long wad column behind the boolit (except it would be somewhat compressed). That same load with wheat bran filler confetti'e the patch just fine and was actually an accurate load. One other thing, the boolit was seated below the neck for a specific test. (Which might explain the riveting I was getting .... mmm!)

[geargnasher]

Maybe the wheat germ filler cushioned the boolit TOO well and it didn't "bump" to fit the bore tight enough to slice the patch. I don't know what your core dimensions are or exactly how thick the patch is, but I don't see any slice marks on that intact patch at all. If your soft lead relies on powder pressure to slug it up tight in the bore, and that pressure is insulated by several inches of wheat germ filler, I would think that the action of bumping as well as the normal gas blast as it leaves the crown would be very much mitigated, thus the patch might survive until a few feet from the muzzle when air resistance would surely peel it away.

Gear

[303Guy]

Yeah. I wonder how far it would go before it came off and ruined the accuracy? Firstly I would have to check that it reliably stays on then head out to the field and do a series of tests.
Aw shucks - see what you've gone 'n done!:mrgreen:

Actually, it was a random patched boolit lying around that I selected but I do know it only went so far into the throat and that's how deep I seated it. It was a fatty, that's all I know. By the way, it was fired in my BSA&M carbine which has a smooth but worn bore. The driving edge of the rifling lands are well rounded toward the breach. It's my cordite modified bore rifle.

This one.
http://i388.photobucket.com/albums/oo327/303Guy/BSAM003.jpg

[6.5 mike]

Without a good air flow around the core & the long filler collum, it may just not have had enough time in flight to shed the patch. Looks like a trip to the great outdoors [smilie=w:.

[303Guy]

I'm am itching to take that little rifle for an outing! But it will be pitted against some potentially fair sized piggy's so I wouldn't want to miss or something. It'll be the back-up rifle so it only actually only needs to put down a maveric charging (or wounded) pig. As long as I can take it for an outing!:mrgreen:

By the way, that patch that survived is soft printer paper.