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Four Thaaangs by Ed Wosika© This is about a few things, none of which is worth an article in itself. All, however, concern CBs. Paco Kelly I became a CBA member around 1980 and immediately found a soul mate in Paco Kelly, whose writings were then featured frequently in TFS. Much later, certain rifle-only elements succeeded in displacing Glenn, as editor, for such heinous things as printing articles about CBs in sixguns (he’s not a shameless hussy. . . more like a shameless Hussar), and Paco migrated to other things in disgust. Well prior to then, I started corresponding with Paco and learned LOTS. He’s the one that got me started designing and making CB-gear — a redesigned version of his original tool, the FREECHEC (this one for plain-based CBs — the Mark IV PB FREECHEC die set), is again available from Hanned [The Hanned Line, P.O. Box 2387, Cupertino, CA 95015-2387, smith@hanned.com, http://www.hanned.com]. I just want to say that I, and we all, owe a great debt to this man for his exceptional CB pioneering spirit and vision. I’m proud to call the fellow-Shootist my friend. If you want to see what he’s doing now, check out his many CB-related articles at www.sixgunner.com. What’s Up With Ed What Paco started stoking me up, he recognized that the seed was already nascent . . . a love of the freedom of experimentation that CBs provide. Nobody can give you the success formula for any given rifle. You have to develop the successful loads yourself, but you can learn from various tricks that others have discovered and shared. If you apply them with care and good scientific observation, then you’ll end up with a really nice load. I don’t care much for competition — not that there’s anything wrong with it. I’m also not especially interested in what kind of accuracy you can obtain if your willing to fork over $3000 for a special purpose rifle — again, that’s fine for those who like it and I love to read what folks have discovered in that line of CB research. What has always interested me is getting the most out of the regular awful-the-shelf rifle, Contender, or sixgun. Most members don’t compete, but they DO own and shoot regular off-the-shelf firearms. I think they and their pieces deserve some R&D work. That’s where I’m coming from. I’ve never made more than really good bubble-gum money making or supporting CB accuracy products. Furthermore, when I write an article, I do it from the perspective that it’d BETTER stand up to repeated re-testing by CBA members. All I’m interested in is pushing out the edges of the CB performance envelope, as it applies to off-the-shelf firearms. Often, that means giving you references to where you can get a given accuracy- or velocity-enhancing gadget or service. I do that only when I feel you’d be well served by that reference. Here’s my challenge to you all. When you find a way to succeed with CB accuracy, please share it with the rest of us. Even a really righteous failure has lots to teach us, and the occasional success or discovery is also good article fodder. RIGHT AN ARTICLE ABOUT IT! For example, I’d really like to hear more about HOW you guys and gals that do so well in the Production category go about finding a rifle that does well and then how your develop your sweet load for it. Don’t keep it under a bushel. Write it up for the rest of us. You can count on me to tell, in my articles, only what I feel you’ll also find if you repeat my work. That’s the only way to do it. I feel that’s the only way for a TFS article to be. Thanks for your ear and your input. Initial Lube Loss Here’s something I’ve not heard discussed before. Tom Grey’s recent article on lube and initial CB seal (against by-passing hot gasses) got me to thinking — and here are the results. If your CB is, as it should be, a bit larger than the barrel’s groove diameter AND the CB is in a the usual jam-fit into the throating, then the additional force resulting from ignition will tend to keep the forward end of the CB rather well sealed from circumferential blow-by. Tom’s point that CB drive bands slightly-oversized for the throat cylinder (up to a half-thou) will help both sealing and guidance is well taken, but the front end of the CB, jammed into the leade-cone, provides the principal seal. However, my concern is about what happens to the lube in the grooves during the short time when before the entire drive band section has transitioned into the rifling. If you’re willing to take a leap of faith that we need to lube our CBs, then have you ever wondered about WHY lube grooves are as deep as they are? Why not deeper? Shallower? As any given lube groove, regardless of its axial length, transitions into the rifling, the lands intrude into the lube groove and displace lube. There’s only one place for it to go — to the rear (the front is sealed). How much lube? For simplicity, let’s talk percentages, 30 caliber, a barrel with 50/50 rifling (land to groove proportion), a 0.310" CB, and a 0.300" bore diameter. Most 30 caliber CBs have a lube groove diameter of between 0.275" and 0.280". Let’s just pick the latter dimension and call it 0.015" deep [ = (0.310"-0.280")/2], or a total depth (add both sides) of 0.030". When the rifling moves into the lube groove it displaces roughly 0.010" of this 0.030" or 1/3, but does this (given our reference barrel) on only half of the circumference. Therefore, it displaces roughly 1/6 of the lube. This lube is pushed to the rear of the CB and does little good except to act like a very small-volume V-Chec (it’s a viscous liquid that must be pushed forward by the gas until a clear gas-cutting channel is produced). The trick is to have enough lube left, AFTER engaging the rifling, to squirt out and float the CB all the way down the barrel as the CB collapses the lube grooves under axial compression from the high-pressure gas (the front of the CB act as a dead weight opposing this acceleration, with the result that the CB is pinched axially and the lube squirts out. . . that is, it does IF you have a CB hardness that roughly matches the load’s peak pressure).. As you can see, a lube groove diameter of only 0.300" would be a sad affair, expelling fully half of the lube upon engraving. I had a custom mould made for me once and didn’t specify the lube groove depth. I couldn’t get it to shoot, so sent it (and the rifle) to Paco. He couldn’t get it to respond either. He sent the rifle and mould back and said that the lube grooves were too cotton-pick’n shallow. I ordered the same design, but with deeper lube grooves. It shot fine from then on. THAT is how we’ve come to our CB’s typically lube groove depths — by finding that shallower ones don’t work. It’s empirical, but it’s valid nevertheless. Moral: Don’t accept any wooden CBs, especially if they have shallow lube grooves. Making A GC Mould A PB In experimenting with The Hanned Line’s new PB FREECHEC die, I’ve found myself hampered by not being able to have similar GC and PB designs to test against each other. That’s over now. Here’s a trick you can use to convert any base-pour GC mould to a PB mould (for use with PB FREECHECs). You’ll need a drill press with an adjustable stop table vise, and a "chucking reamer" of appropriate diameter from MSC [1-800-645-7270 || http://www.mscdirect.com/ ] or other machine-tool supply source. The reamer will run around $20 to $30, depending on maker and diameter. It’ll take you about 15 minutes to change a two cavity mould to PB configuration, and the results will be a very high quality conversion. Order the correct size of chucking reamer (the mould’s drive band diameter or up to 0.005" smaller). Mount your GC mould in the drill-press vice and make it as level as possible, by eye. Install the reamer in the chuck and lower the table until the bottom of the reamer has a bit of clearance above the mould. Lower your reamer and use it to adjust the mould’s location until the reamer is, by eye, dead-on-center (i.e., it doesn’t bend to one side when it meets the gas check shank hole in the mould). If possible, lock the table and vice in this position. Set the quill stop for a bit under a tenth of an inch of penetration (0.070", as that is the internal height of a PB FREECHEC). LEAVE THE MOTOR OFF!! While pushing quill down GENTLY, turn the chuck by hand in a clockwise direction. The reamer will advance smoothly to full depth and will then turn easily. Raise the quill and verify, visually, that you have about the right depth. Move the other cavity under the reamer (dead on-center) and do it. Both cavities will have just the same depth. It doesn’t hurt to leave some of the check shank alone, as this leaves room for a bit of lube ahead of the sized-on PB FREECHEC. What diameter of chucking reamer should you order? If you’re going to shoot the CB bare-ass, then match the CB’s as-cast band diameter. Otherwise, try the following ranges, but going for the smaller end of the diameter range will make it easier for the PB FREECHEC to size on and will not affect the check’s outside diameter: 30 caliber = 0.305" to 0.310" diameter chucking reamer; 35 caliber = 0.354" to 0.358"; 41 caliber = 0.405" to 0.410"; 44 caliber = 0.425" to 0.430"; 45 Pistol = 0.448" to 0.452"; 45 Rifle = 0.455" to 0.458". Don’t forget that you can pool the purchase of the reamer and then share it. If you spread the cost of the chucking reamer around, then the results is, for all purposes, a custom PB mould (not available for sale) for around $40. You can then make all the checks you want for it, from aluminum beverage can material, with your PB FREECHEC die set and can convert a new copy of each of your favorite GC moulds to use with it.
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