BB, camera still hates you! What am I looking at? Did those used to be gas seals? Maybe the Blue Dot is a better choice? Mine look like I could use 'em again.
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BB, camera still hates you! What am I looking at? Did those used to be gas seals? Maybe the Blue Dot is a better choice? Mine look like I could use 'em again.
The 70g charge of 4759 also trashed the wads. I am going to order some new 3" hulls and decide what wads to use in place of the x12x gas seals.
BB
bikerbeans,
Find some tight hull fitted shot wads, cut the overpowder part of the wad and use it in place of the x12x or any other factory gas seal (they simply do not work because of faulty design). Adjust the free hull place using hard (nitro) cards and felt wads.
BB:
What are you doing using jellyfish under zlugs? Wait, those used to be gas seals!?! Well, they look like jellyfish (or at least the remains of jellyfish) now anyway.
I've had some bad blowouts but nothing that looks quite like that. it looks like gas was blowing by and stripping plastic along with it.
Longbow
BB,
I have 000 experience with that powder but lots with x12x seals. I've loaded some Bazooka loads and never had a failure like that. Almost like they were canted over the powder - or something. Anyway, it just don't add up I tell ya!
It looks like the x12x gas seals are a bit too small in diameter for the bpi hull. I have used their x10x seals over 95g of 4759 with a 740 HB slug without this problem but I was using federal hulls. I will go though my collection of wads and hulls and try to find a tighter fitting combo.
While I am waiting to get the Zlugs powder coated I will try the 770g WW-Zlugs. I also have a bunch of 730 grain HB slugs so i better call blue cross and get pre-approved for rotator cuff surgery.
BB
It could be a sign of too high muzzle pressure, gas blowing them as they escape the bore and shredding them.
i had that when i was working on my 20ga Tri-ball loads, and RMc said that they had a similar problem unless they reduced the powder charge by a grain or so (of Blue Dot, not 4759) or else used a barrel 24" long (as opposed to 20"); both reduced the muzzle pressure to the point where the seals didnt fail.
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"...the civil libertarians and rationalists who are ever on the alert to oppose tyranny "failed to take into account man's almost infinite appetite for distractions." In 1984, Orwell added, people are controlled by inflicting pain. In Brave New World, they are controlled by inflicting pleasure. In short, Orwell feared that what we fear will ruin us. Huxley feared that what we desire will ruin us. This book is about the possibility that Huxley, not Orwell, was right.” -N.Postman
Isn't that what Greg warned about with slower powders?
I got it from RMc, but i bet ya 3-and-a-half cents, give or take a nickle, Greg knows it too.
____________
"...the civil libertarians and rationalists who are ever on the alert to oppose tyranny "failed to take into account man's almost infinite appetite for distractions." In 1984, Orwell added, people are controlled by inflicting pain. In Brave New World, they are controlled by inflicting pleasure. In short, Orwell feared that what we fear will ruin us. Huxley feared that what we desire will ruin us. This book is about the possibility that Huxley, not Orwell, was right.” -N.Postman
Well, I guess I missed that one! Generally I have not had the problem using Blue Dot or SR4756. The only time I have shredded plastic like that was when I decided to use up some old shotcups I had cut the gas seals off for wad slugs using nitro card wads over the powder. Yikes! There is a lot of gas leakage past nitro card wads let me tell you... cut those shotcups up badly.
I never thought about high muzzle pressure as being a problem but then I have not had many gas seals blow out badly except Win AA Reds.
I will use good gas seals under the Brenneke zlugs which hopefully will be shot this weekend.
Longbow
I had some PT1205 wads look like that the other day when shooting Lee 1 oz slugs over 49 grains of BlueDot.
Are those signs of over pressure?
How did ur Tri Ball loads turn out? I'm messing around with them now.Originally Posted by cpileri
That seems like a huge load of powder to move 1 oz. Looks like the wads think so too. Any trouble ejecting hulls? Is the brass marked hard by the extractor? Any sign of leakage around primer? If yes to any come off that charge.
What kind of Hard Cards are You Guys using between the Zlug and the Seal?
Good Cards make a great deal of Difference. BPI has some Waxed Cards that hold up under Pressure.
Circle Fly has some 1/4" Cards that do well, but shred upon leaving the Barrel. Your Probably getting some Blowby in the Hull, because the Walls are so Thin on some Brands. You could proably even use a Waxed Card in place of the GS. X12X are great Seals. The OB12 can also work, but it depends on the Hull. If cost isn't an Issue the Ferderal .090" Hulls are the best on the Market. They also have the most internal Capacity on any currently available Hull.
Greg
AKA 12 Bore
Yeah, 49gr is a lot of blue dot to move 1oz. what load data did you base that on?
Anyway, in the pic of three wads: the one on the left seems to have the skirt mangled, which could be a sign of gas blowby. It could also be mangled by a rough bore or by hitting something on the ground. the other two have skirts that are OK, but the rest of the wad is pretty well banged up.
The 20ga tri-bal turned out pretty well: 20gr Steel in PT wads, group nicely, still have to test them for penetration; which I plan to do when I test the zlugs. I am saving newspaper to make wetpack now.
http://castboolits.gunloads.com/show...20-ga-Tri-ball!
C-
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"...the civil libertarians and rationalists who are ever on the alert to oppose tyranny "failed to take into account man's almost infinite appetite for distractions." In 1984, Orwell added, people are controlled by inflicting pain. In Brave New World, they are controlled by inflicting pleasure. In short, Orwell feared that what we fear will ruin us. Huxley feared that what we desire will ruin us. This book is about the possibility that Huxley, not Orwell, was right.” -N.Postman
49 gr of Blue Dot is the max charge for 1 oz Lee slugs in the data provided with the mold, but it's for WAA12 wads. PT wads have a much bigger and more efficient gas seal, so these are almost certainly over 1800 fps. I don't know all the details of this load, but it's probably OK pressure with Blue Dot, just more than the wad can handle, since it's designed to handle 1 oz at 1300 fps.
If its a max load w 1oz slugs, I'd back off: worried abt the pressure. Changing wads can change the pressure, and you do have evidence that its high. It MIGHT be the same and might even be lower, but why chance it? that might help your wad mangling problems too.
____________
"...the civil libertarians and rationalists who are ever on the alert to oppose tyranny "failed to take into account man's almost infinite appetite for distractions." In 1984, Orwell added, people are controlled by inflicting pain. In Brave New World, they are controlled by inflicting pleasure. In short, Orwell feared that what we fear will ruin us. Huxley feared that what we desire will ruin us. This book is about the possibility that Huxley, not Orwell, was right.” -N.Postman
I got the load data from Lee slugs except I substitute WAA12 for PT1205. I have no other signs of pressure.
I'll drop the charge on the next batch. Thanks guys!
And can someone explain to me why shooting shot has more pressure than shooting slugs of the same weight?
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