njc110381 Posted November 5, 2009 Report Share Posted November 5, 2009 Right guys, next problem! I'm forming brass for the .17AH. I've magically got rid of the old loaded rounds and now have 70 cases to form, some N120 powder and some 20 grn bullets I've been told that 10.8grns splits cases, so I dropped back to 10. That split the case but only very slightly. So I backed off another half a grain to 9.5 and tried that. I now have two bigger splits and the shoulder isn't fully formed. So, would you say that's bad cases, poor choice of powder to do the job, or something else I've done wrong? The cases have splitjust below the shoulder which I assume is normal because that's where the most stretching is going on? I'm confused (but it's still fun!). Link to comment Share on other sites More sharing options...
pnse Posted November 5, 2009 Report Share Posted November 5, 2009 Right guys, next problem! I'm forming brass for the .17AH. I've magically got rid of the old loaded rounds and now have 70 cases to form, some N120 powder and some 20 grn bullets I've been told that 10.8grns splits cases, so I dropped back to 10. That split the case but only very slightly. So I backed off another half a grain to 9.5 and tried that. I now have two bigger splits and the shoulder isn't fully formed. So, would you say that's bad cases, poor choice of powder to do the job, or something else I've done wrong? The cases have splitjust below the shoulder which I assume is normal because that's where the most stretching is going on? I'm confused (but it's still fun!). try 11grns as a fireforming load,you may have to anneal the brass after forming,powder will not cause the splits work hardening of the brass is the culprit atb paul Link to comment Share on other sites More sharing options...
grahamfarmer Posted November 5, 2009 Report Share Posted November 5, 2009 hi njc , google 17 ackley and several links come up including a couple about forming and fire forming the cases most seem tosuggest using new brass and several powders are recommended but none mention n120 . eems your need to learn how to anneal as well . so keep us posted. graham. Link to comment Share on other sites More sharing options...
baldie Posted November 5, 2009 Report Share Posted November 5, 2009 Anneal the cases njc. As previously mentioned, the brass has work hardened, it doesn,t take much. You will never hurt a case by annealing, providing you dont come more than a third down the case. Folk who have it off to a fine art, sometimes enjoy up to 50 firings per case, when annealed every time, or couple of times. I,ve just built a case annealing machine, and am having great fun with it. It will do a hundred cases in 10 minutes. Link to comment Share on other sites More sharing options...
njc110381 Posted November 5, 2009 Author Report Share Posted November 5, 2009 I tried annealing a couple in a pretty basic and DIY manner. It worked, no more have split. I'll do the rest tomorrow. I did a bit of reading and it seems that if you don't cool the head end of the case it can be rather dangerous? I went with the tray of water method. Stood the cases in the tray, covered 1/2 to 2/3 or the case with cold water, cooked the top of each one with my butane torch for ten seconds then tip it over into the water. Worked a treat as far as I can see! Baldie, this machine you've made? How does it work? It sounds great, especially if you can just go off and leave it to it! Link to comment Share on other sites More sharing options...
baldie Posted November 5, 2009 Report Share Posted November 5, 2009 Here you go, i actually mailed these guys, and they would ship here, but wanted $200 on top of the $400 for the machine, to ship . I thought that was excessive, so copied it. I used a windscreen motor, and a speed controller, to make it all work. The hard part was marking out the big wheel exactly, and cutting all those holes and teeth by hand, keeping them all equidistant. It was good fun, and it works perfectly. Mine runs off a maplins 12 volt power supply. http://www.zephyrdynamics.com/page3.html 10 seconds for such a small case sounds a lot, but that depends on the size of your torch flame i suppose. Get your hands on a product called Tempilaq, its a paint that shows when the temp is reached, and comes in various levels of temp. Tim Hannams has it, i saw some on their shelves yesterday. Do a search on 6mmbr.com, for annealing....it has all the info you will ever need. Link to comment Share on other sites More sharing options...
MarinePMI Posted November 5, 2009 Report Share Posted November 5, 2009 Baldie, I've mentioned this on another web site, but I think a circular saw blade would work rather than having to cut all the teeth. Then you'd just have to worry about inset holes, which I'd wager could be punched out with a stamp of sorts... Just a thought... Link to comment Share on other sites More sharing options...
Andrew Posted November 6, 2009 Report Share Posted November 6, 2009 Baldie, I've mentioned this on another web site, but I think a circular saw blade would work rather than having to cut all the teeth. Then you'd just have to worry about inset holes, which I'd wager could be punched out with a stamp of sorts... Just a thought... Howdy Marine! I survived the hospital so you may have to wait a few years longer to get a crack at the .218 Bee! PS: Have you been seating the bullet into the lands to fireform? I got thinking about your circular saw idea. Brilliant. I would add that you could arrange the single cog to engage the teeth immediately after the drop out hole and before the spot where you set the case into the assembly. A thin sheet metal shoulder around the circumference of the blade would keep the cases from rolling out. Just a thought. Neat rig. I may build one to rework 357 Magnum to .256 Winchester Magnum.~Andrew Link to comment Share on other sites More sharing options...
baldie Posted November 6, 2009 Report Share Posted November 6, 2009 Marine.... Just after i,d finished several hours of sawing , filing etc.....i looked at it....and thought....this looks like a circular saw blade now...... I,ve never been the sharpest knife in the drawer. A blade would have to be de-tempered somehow i reckon, to be able to drill/punch the holes. If you look however, the holes are actually diamonds....for a good reason. As it turns, it automatically centres the case at the rear middle of the hole. Very clever idea. Link to comment Share on other sites More sharing options...
Cornishman Posted November 6, 2009 Report Share Posted November 6, 2009 I use 11.3g of N120 as my fireforming load and get no splits. That's with Remington brass which I've found to be best and withstands about 5 loadings with neck sizing before I have to anneal and f/l resize. Ten seconds in a butane flame seems to work for me (because after that my fingers burn even with gardening gloves on!) and I have some cases now on their 12th firing with no splits. Cornishman Link to comment Share on other sites More sharing options...
MarinePMI Posted November 6, 2009 Report Share Posted November 6, 2009 Baldie, Yep, I thought about the need to anneal the blade, but figured that was what the machine was for, so just build everything but the holes, and turn the torch on the blade itself to anneal it. Then, mark out the corners of the holes, drill and then broach with an arbor press. Clean up the holes with a small end mill to cut out the remaining metal and voila, put it back to gether and be done with it. Andrew, Dang, I've had my eye on the Bee for awhile now... Link to comment Share on other sites More sharing options...
njc110381 Posted November 7, 2009 Author Report Share Posted November 7, 2009 I use 11.3g of N120 as my fireforming load and get no splits. That's with Remington brass which I've found to be best and withstands about 5 loadings with neck sizing before I have to anneal and f/l resize. Ten seconds in a butane flame seems to work for me (because after that my fingers burn even with gardening gloves on!) and I have some cases now on their 12th firing with no splits. Cornishman That's interesting. I'm using a Rothenberger butane torch. It's got quite a wide flame with no pencil type inner flame which is designed to evenly heat copper pipe for plumbing joints. I've just picked up some MAPP gas for it (a propane/acetylene mix) which should reduce the heating time a little. Not that I know what I'm talking about, but I'm a bit concerned about the gloves method you mention. Do you not cool the base of the case whilst heating the top? I read that it's important to keep the bottom cool for safety reasons? I've just sorted a new method. Two pyrex bowls, one big and one small. I fill the large bowl with water then roll the smaller bowl into it upside down so there's something for the cases to stand on. Get the water level to 2/3 up the case and torch them, then knock them over. Give it a go, it will keep the base of the case cooler and save you burning your fingers! Link to comment Share on other sites More sharing options...
pnse Posted November 7, 2009 Report Share Posted November 7, 2009 the best method i have found for annealing my 17 ackley hornet cases is:- here are the tools i use no.1 a Rothenberger butane torch,no.2 a small hand screwdriver with a Sinclair case drive and holder combo Visit My Website with a lee auto prime shelholder. with these you can turn the case in the flame with the tip of the flame on the case neck whilst watching for the color change which will start on the neck and move down the case to where your shoulder will eventually form,with a bit of practice you will get to know the color you are looking for which has a blue/green tint when this has moved down the case dip the case in water and throw it on a towel and do another with this method you can do a 100 cases in about a half hour,when all the cases are done i dry them with a hair dryer here is a case between two that have been annealed [i hope you can see the difference] atb paul Link to comment Share on other sites More sharing options...
njc110381 Posted November 7, 2009 Author Report Share Posted November 7, 2009 This is my way of doing it which seems to work..... I fire the blowtorch directly down on the top of the case so the flame wraps itself around the case. The discolouration looks fairly even doing it like that and I haven't split any cases yet. From that I assume it's working ok! I dried my cases in the oven, ten minutes at 180c! According to what I've been reading you can take them up to 250ish without affecting the brass at all? Link to comment Share on other sites More sharing options...
Cornishman Posted November 7, 2009 Report Share Posted November 7, 2009 That's interesting. I'm using a Rothenberger butane torch. It's got quite a wide flame with no pencil type inner flame which is designed to evenly heat copper pipe for plumbing joints. I've just picked up some MAPP gas for it (a propane/acetylene mix) which should reduce the heating time a little.Not that I know what I'm talking about, but I'm a bit concerned about the gloves method you mention. Do you not cool the base of the case whilst heating the top? I read that it's important to keep the bottom cool for safety reasons? I've just sorted a new method. Two pyrex bowls, one big and one small. I fill the large bowl with water then roll the smaller bowl into it upside down so there's something for the cases to stand on. Get the water level to 2/3 up the case and torch them, then knock them over. Give it a go, it will keep the base of the case cooler and save you burning your fingers! OK, I guess I should fess up here and admit that I've only ever annealed Hornet cases (for my 17AH) not other types of cases. Working from ever-reliable first principles I figured that a low-pressure cases with thin brass should be relatively easy to anneal with a quick in-and-out of a blowtorch flame - not enough time for the heat to travel to the lower part of the case. I use gardening gloves to protect my fingers as I twirl the cases in the flame. Low tech but I've done many hundreds of cases and no problems. I'll try your way next time and let you know how I get on. Cornishman Link to comment Share on other sites More sharing options...
njc110381 Posted November 8, 2009 Author Report Share Posted November 8, 2009 Fair enough. If it works then it must be ok! You may be right about the thin brass, I just got a bit scared of weakening the case and having a head seperate on me so did mine in water to be on the safe side! I fired about 20 rounds today and none of them split. I'm pretty happy with my results Link to comment Share on other sites More sharing options...
Alycidon Posted December 28, 2010 Report Share Posted December 28, 2010 I have now acquired NJC's 17AH and am advised almost everywhere that annealing is the answer, Dave you mentioned this Tempilaq paint, what temperature do we need?, 475 ( C or F ?) seems to ring a bell somewhere?. Thanks A Link to comment Share on other sites More sharing options...
Foxshooter Posted December 28, 2010 Report Share Posted December 28, 2010 I have now acquired NJC's 17AH and am advised almost everywhere that annealing is the answer, Dave you mentioned this Tempilaq paint, what temperature do we need?, 475 ( C or F ?) seems to ring a bell somewhere?. Thanks A you want 475F/246C and buy a bottle of thinners while you are about it. I have been advised to remove the tempilaq before the brass cools to make it easier. Mark Link to comment Share on other sites More sharing options...
Elwood Posted December 28, 2010 Report Share Posted December 28, 2010 you want 475F/246C and buy a bottle of thinners while you are about it. I have been advised to remove the tempilaq before the brass cools to make it easier. Mark And good advice it is, I use a damp cloth and just wipe it off, if you let it harden after it liquidises then it's a wire wool job and a right pig. Link to comment Share on other sites More sharing options...
baldie Posted December 28, 2010 Report Share Posted December 28, 2010 Tim Hannam,s stock tempilaq, Geoff. Link to comment Share on other sites More sharing options...
Foxshooter Posted December 28, 2010 Report Share Posted December 28, 2010 Try these guys http://www.industrial-markers.co.uk/prodMain.aspx?rangeCode=TLAQ&br=14_118 I found their prices to be very good Mark Link to comment Share on other sites More sharing options...
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