November 5, 2017, 07:30 PM | #26 |
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The Amp is the Cadillac of case annealing machines for sure. It is supposed to give the perfect anneal. With my budget I will settle for getting consistent and convenient anneals.
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November 5, 2017, 11:23 PM | #27 |
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One reason I went with the AMP is because I now reload inside the house. I use to use my shed but thieves broke in and stole my scales. That's all they took. So now I'm inside and open flame is a no no. It takes very little time to anneal 50 cases. They are also promising an auto loader for about $300. I'm not interested in the loader because I have plenty of time on my hands. I also only work with two cartridges. I am also in a small room and the AMP unit is fairly small. I also have a little crow trimmer and it is very accurate and quick. I know there are places where I could shorten my reloading process. I choose not to short cut it.
Right now I'm trying to see the difference changes make. I'll start with the bolt guns and move to the semis. |
November 6, 2017, 08:12 AM | #28 | |
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Annealing is just one facet of case preparation. Along with other techniques it can lower the SD of your velocities. Unless you are shooting at medium to long range ( 300 +) with a .5 or less rifle or you are a benchrest shooter who already shoots .25 or less 5 shot groups already at 100 - 200 you won't see much if any difference
A good article on real world results from lowering the SD can be found here http://precisionrifleblog.com/2015/0...oes-sd-matter/ Quote:
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November 6, 2017, 10:58 AM | #29 | ||
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RC20,
I'm curious why the paint and stick results would be any different? In the past I actually filed some dust off the stick and mixed it with alcohol to apply it in order not to have to pre-warm the case to get a smooth application. Seemed to work fine, too. If you feel unsure about the liquids, you can bracket them with several temperatures at a time. See which ones melt simultaneously with the stick you like. Quote:
With the Sinclair tool, I use an entirely different approach. I either uniform the primer pocket depths or measure and sort them. I gently do the same with primer height. I then subtract the primer height from the pocket depth and add 0.003" to the result. I use shim washers between the Sinclair tool's body and the case clamping collar to set the protrusion of the primer ram protrusion to match that resultant number. I then prime by pushing the handle all the way to reach that depth setting. As Dan Hackett reported in '95, you can get your velocity SD's down this way. Quote:
BTW, I found in the past that if you look closely (magnifier) at the case mouths of some commercial ammo, you can find copper scraped off the bullet in a little ring at the case mouth. This is due to the edges of the case mouth being sharp. The same happens with a freshly chamfered case. Despite the angle, the the corner it makes with the ID of the rest of the neck frequently has a wire edge burr and scrapes bullets and coatings. I found I could take a freshly chamfered case and insert and then pull a moly-coated bullet, and the pulled bullet would have no visible moly below the case mouth line. I also found burnishing the chamfer eliminated the problem. Bart Bobbit was familiar with this and suggested using an E-Z Out screw extractor in a drill for this. It has a left-hand conically tapered coarse "thread" pattern for extracting stuck screws. I polished one up that covers .22-45 cal case mouths. After trimming and chamfering, brief contact with it burnishes the sharp edge off. However, a little additional time in the SS pin tumbler after sizing and trimming and chamfering will do the same thing for you and allow coated bullets to keep their coatings.
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November 6, 2017, 12:49 PM | #30 |
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After trimming and deburring, I have noticed the tumbling does indeed polish the edges and allow easier seating without shaving the bullet. I will probably try my spray on case lube on my next series of reloading.
Stupid me I lost my large primer stem for my sinclair primer tool, and have ordered a Frankford Aresenal tool that has an adjustable seating depth built in. I look forward to trying this tool when it arrives. The measuring primer depth and subtracting primer height has me confused. I suppose you could only measure on the outside of the cup because the height in the center is affected by the anvil. I also look forward to moving to my lapua brass which is palma brass. I should have my first test tomorrow for ES on annealed brass. Need to build bullets and shoot. Thanks again to everyone. The deeper I get into this subject the deeper it gets. Thanks. |
November 6, 2017, 04:09 PM | #31 |
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Interesting info on the primer seating. After reading this thread I went back and checked a bunch of cases that I had just primed and with the help of a dial indicator and a hastily rigged jig I found that indeed the primers were not uniformly seated. I put the priming arm on the press and went back and reseated them using "moderate" force. On rechecking they are all at least seated at a uniform depth. If it is like most aspects of shooting the key would be consistency. These cases are too be used in a load test of a new powder possibly on Thursday so I will take the chrono and see how my SD's look. Anything that may eliminate a flyer is a good thing
I guess sooner or later I may end up with one of these http://www.xxicsi.com/stainless-steel-priming-tool.html edit - that was also a interesting idea on the burnishing. Using the chamfer tool in a cordless drill ran counterclockwise seemed to do a decent job. I bet a countersink likewise ran backwards would also probably work
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November 6, 2017, 04:28 PM | #32 |
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You might also look here:
https://www.sinclairintl.com/reloadi...prod37732.aspx I ended up with: https://www.midwayusa.com/product/58...d-priming-tool The latter does not have as tight of tolerances, but good feel. It is also tray fed. So far I rate it good for the price. |
November 6, 2017, 05:08 PM | #33 | |
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At the moment I have my SD under control and to the point I wanted it to be. Just as the article I linked earlier pointed out that lowering the SD has a diminishing return. I have hit that diminishing returns point now and my toy money is best spent on bullets, powder, primers and practice more practice and even more practice and maybe a new stock for Christmas Please keep posting on your quest for low SD's, I enjoy these diuscussions and always seem to pick something up from the thread. It took me a couple of months of small changes for me to start hitting single and low double digits on my rounds and the best advice I can offer is try and make every round just like every other round in every aspect from the primer to the bullet
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November 7, 2017, 02:01 PM | #34 |
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Jugornot,
The primer height I am referring to is from the bottom of the cup to the tops of the anvil feet. The feet are what touch the bottom of the primer pocket and the anvil tip needs to be forced 0.003" deeper into the priming mix during seating. You measure primer height gently so you don't accidentally get a bad measurement by starting to compress the anvil into the cup. Consolidation (assembly into a unit) of the cup, mixture, foil, and anvil happens at the primer factory. Reconsolidation is that additional 0.003" of compression of the anvil into the foil and mixture. It optimizes sensitivity and consistency of the mixture combustion by pre-loading any cushioning by the foil (actually made of paper these days; the old cap and ball percussion caps used actual metal foil as a moisture seal and retaining cover) and uniforming the amount of priming mix filling the gap between the inside bottom of the primer cup and the tip of the anvil, which also affects cushioning of the firing pin.
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November 7, 2017, 02:49 PM | #35 |
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Good News and then what the heck:
Series Shot Speed 9 1 2886 ft/s ---- ---- ---- ---- Series 10 Shots: 5 Min 2868 Max 2886 Avg 2876 S-D 7.6 ES 18 Series Shot Speed 10 1 2876 ft/s Group Size O-t-O C-t-C 10 2 2868 ft/s 0.98 0.68 10 3 2881 ft/s 10 4 2886 ft/s 10 5 2869 ft/s ---- ---- ---- ---- Series 11 Shots: 5 Min 2880 Max 2897 Avg 2884.6 S-D 7.1 ES 17 Series Shot Speed 11 1 2881 ft/s Group Size O-t-O C-t-C 11 2 2881 ft/s 0.82 0.52 11 3 2880 ft/s 11 4 2897 ft/s 11 5 2884 ft/s ---- ---- ---- ---- Series 12 Shots: 5 Min 2855 Max 2904 Avg 2880.6 S-D 21.0 ES 49 Series Shot Speed 12 6 2900 ft/s Group Size O-t-O C-t-C 12 7 2855 ft/s 0.71 0.41 12 8 2904 ft/s 12 9 2868 ft/s 12 10 2876 ft/s ---- ---- ---- ---- First 2 groups were improvement on a good scale. The last was a disappointment. The only thing I did differently from normal was the primer seating. Because I did not have my new priming tool yet, I seated these primers on my press. It was the first time I had ever used the press for this purpose. I will conduct another test probably this weekend or next week. A cold has kept me from other chores for the past few days. I mention the primer difference because I was amazed at the difference in pressure required for the press. I know it is mechanical advantage that makes the hand seaters feel easier, but I had to reseat several of the primers because they were not level. Next test will rule primers out to some extent. Still working on a measurement for primers below head. |
November 7, 2017, 07:23 PM | #36 |
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Keep a running average of the SD's. Just as one 5 shot group does not make or break a 5 shot SD can go to extremes also. Right now you have a running average of 12. That is below factory which averages 15 FPS deviations. I kept a spreadsheet going for a couple of months and still log the results when I am shooting from the bench and have a chrono set up
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November 11, 2017, 11:43 PM | #37 |
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on the primer seating. I am not sure if it was the double seating of the primers, the new powder I was testing, or the neck lube or all three but I did a load test yesterday and three of four sets I chrono'ed were several FPS lower than normal. Not sure what happened at 44.0 gr
Name: Nosler Range Test Notes: Powder test 44.1gr Shots: 5 Average: 2731 FPS SD: 8 FPS Min: 2721 FPS Max: 2743 FPS Spread: 22 FPS Barometric Pressure: 30 Temperature: 50 -------------------------- Name: Nosler Range Test Notes: Powder test 44.5 gr Shots: 5 Average: 2728 FPS SD: 4 FPS Min: 2726 FPS Max: 2737 FPS Spread: 11 FPS Barometric Pressure: 30 Temperature: 50 -------------------------- Name: Nosler Range Test Notes: Powder test 44.3 gr Shots: 5 Average: 2739 FPS SD: 10 FPS Min: 2721 FPS Max: 2749 FPS Spread: 28 FPS Barometric Pressure: 30 Temperature: 50 -------------------------- Name: Nosler Range Test Notes: Powder test 44.1 gr Shots: 5 Average: 2730 FPS SD: 7 FPS Min: 2726 FPS Max: 2743 FPS Spread: 17 FPS Barometric Pressure: 30 Temperature: 50 -------------------------- Name: Nosler Range Test Notes: Powder test 44.0 gr Shots: 5 Average: 2681 FPS SD: 43 FPS Min: 2609 FPS Max: 2721 FPS Spread: 112 FPS Barometric Pressure: 30 Temperature: 50 --------------------------
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November 15, 2017, 02:07 PM | #38 |
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I went to the range yesterday. I was trying some load development for my bolt gun using my 308 palma brass. I did two 10 shot ladders with 175 and 168 smk. It was during the loading of these that I became frustrated with my scales. I have a Lyman gen 5 auto dispenser, a Lyman 1500 electronic scale and a smartweigh cheapo .02 grain scale. Some background info. I was an apprenticed instrument tech/electrician. I later was an instrument tech. All of this over a 40 year career. I have calibrated scales from 10,000 lbs to tenths of a gram. All this said I know when a scale has problems. The most reliable of my 3 scales is the Lyman 1500. The gen 5 is consistently .1 or .2 grains low. this is ok because I would trickle to a final weight. But I was trying for better accuracy with the smartweight. This is a replacement for a Gempro 250 which was stolen along with my first gen 5. Any way a new A&D FX120i is on its way with an auto trickler. I am lerning the old adage buy once cry once time and time again. The cheap .02 grain scales vary up to .2 tenths when zeroing the pan.
I know this was originally about my annealer, but it is morphing into a precision reloading thread. Anyway thanks for all the help and any more is welcome. Thanks again guys. |
November 15, 2017, 03:59 PM | #39 |
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getting back to annealing for a minute.
I am a huge fan of Bryan Litz and own a couple of his books but do not own Modern Advancements in Long Range Shooting Vol. 2. Apparently he did some annealing tests in this volume and came to the conclusion that annealing has no benefit on group sizes. I myself have seen tremendous improvements in my SD's over the last few months along with fewer and fewer flyers. Pretty much the ones I do see are due to operator error and generally called before I see them. I see shooters obsess over neck bushings, trimming, and even turning necks to get what they feel to be the proper neck tension. It baffles me why the condition of the metal would have no benefit since obviously it does affect the springback of the necks. Granted I have also been working on getting more precise with the neck trimming, and other preparations as well as my range techniques at the same time so the annealing every firing may not be as necessary as I think. I am saving my shooting money right now for a new stock and scope or I would buy the book just to read that one chapter. I would love to find out what method he was using and how often. If any here have the book and would like to educate us on the method used and how frequently along with the results it would be appreciated. Regardless with my current equipment it is a pretty easy operation and as I am fond of saying "if it works for you then don't change it without a good reason " so I will most likely continue to anneal after every firing.
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December 15, 2017, 10:43 AM | #40 |
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Went to the range yesterday. Trying to roll all my techniques into a ladder process. It includes annealed brass and seating primers to .003 crush. The brass is no longer a problem as it resizes and trims like new. The new scale is much better than either the Myweigh or Smartweigh scales. The autotrickler works great. So many things coming into focus and I received some of the lowest SD and ES ever. So here's the data.
--------------------------------------------------------------------------------- Min 2782 Max 2818 Avg 2800 S-D 18 ES 36 Series Shot Speed 1 1 2802 ft/s 1 2 2782 ft/s 1 3 2818 ft/s ---- ---- ---- ---- Series 2 Shots: 3 Min 2809 Max 2814 Avg 2811 S-D 2.6 ES 5 Series Shot Speed 2 1 2814 ft/s 2 2 2809 ft/s 2 3 2810 ft/s ---- ---- ---- ---- Series 3 Shots: 3 Min 2811 Max 2815 Avg 2813 S-D 2 ES 4 Series Shot Speed 3 1 2814 ft/s 3 2 2815 ft/s 3 3 2811 ft/s ---- ---- ---- ---- Series 4 Shots: 3 Min 2815 Max 2837 Avg 2824 S-D 11.5 ES 22 Series Shot Speed 4 1 2820 ft/s 4 2 2837 ft/s 4 3 2815 ft/s ---- ---- ---- ---- Series 5 Shots: 3 Min 2811 Max 2844 Avg 2826 S-D 16.6 ES 33 Series Shot Speed 5 1 2844 ft/s 5 2 2824 ft/s 5 3 2811 ft/s ---- ---- ---- ---- Series 6 Shots: 3 Min 2845 Max 2858 Avg 2851 S-D 6.5 ES 13 Series Shot Speed 6 1 2850 ft/s 6 2 2858 ft/s 6 3 2845 ft/s ---- ---- ---- ---- Series 7 Shots: 3 Min 2842 Max 2869 Avg 2855 S-D 13.5 ES 27 Series Shot Speed 7 1 2869 ft/s 7 2 2842 ft/s 7 3 2854 ft/s ---- ---- ---- ---- Series 8 Shots: 3 Min 2853 Max 2863 Avg 2859 S-D 5.2 ES 10 Series Shot Speed 8 1 2863 ft/s 8 2 2861 ft/s 8 3 2853 ft/s ---- ---- ---- ---- average Shot 1 Shot 2 Shot 3 2800 45 2800 2802 2782 2818 2811 45.2 2811 2814 2809 2810 2813 45.4 2813 2814 2815 2811 2824 45.6 2824 2820 2837 2815 2826 45.8 2826 2844 2824 2811 2851 46 2851 2850 2858 2845 2855 46.2 2855 2869 2842 2854 2859 46.4 2859 2863 2861 2853 From the graph I attached, if I would pursue a load I would load 10 or 15 at 45.2, 45.3, and 45.4. Thanks to all who replied, especially Hounddawg and Unclenick. I know they are only 3 shot groups, but they are the lowest spreads and deviation I have ever shot. |
December 15, 2017, 02:20 PM | #41 | |
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If I get the time I will pursue that with Templiq, but the difference is significant and I found it unreliable. Crayons are not the best answer either, you have to catch the case at max heat and then you have the cool off factor as well as the cooling affect of the crayon. Not an issue on dense metals, but thin brass, I don't think its spot accurate. Ergo, I have taken a creep up approach. I find the rough timing, push it over the edge to where I get a minimal glow (dar4k room) drop that down, significant time wise, then cross check with a crayon. It seems to work. I believe its bringing them in a bit below ideal temperature but I am not worried about that , I am annealing often enough that no cracks yet. My take is this is a very hard area to get provable results short of quasi factory setup like Jeephmmaer has. Therein lies the rub, you need that to actually prove your results with a quality control process if you want to say 100% your efforts are there. Mine are good enough for amateur work.
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December 15, 2017, 04:51 PM | #42 | |
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Quote:
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December 16, 2017, 11:45 AM | #43 |
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Jugornot,
Congrats on the lower SD's. That's the result you get when seating primers correctly and if you handle the cartridges so the powder position in the cases is same for every shot. The next thing to learn is if your POI and velocity sweet spots coincide. Either the Audette Ladder (under Incremental Load Development) or Dan Newberry's OCW round robin can tell you that. RC20 and Jeephammer, Have either of you guys applied same-temperature crayon and liquid to a case and verified they turn at the same time in a flame, but not at the same time in an induction annealer? Or at the same time when heated slowly, but not when heated quickly? Since these compounds are basically high temperature waxes, and since, even if there were metal particles in them, the particles would be small and separated by insulting wax and therefore unable to carry eddy currents to make heat (insulated particulate composition is how eddy current heating losses in the ferrite core materials are prevented), it should make no difference other than to thermal conductivity of the material. What I can imagine, without conducting the test myself, is that the dried liquid and crayon would have differing intimacy of contact with the metal surface and differing thermal conductivity. This would result in different response speeds, thus appearing to turn at different temperatures during fast heating when one of them is actually just responding faster than the other can do. If there is actually some difference, just grind up some Tempilstik and mix into a slurry with alcohol and paint on. Works fine.
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December 16, 2017, 12:54 PM | #44 | |
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I did a test a few years ago ( data not in front of me ) that showed changing how you hold the rifle effects ES/SD significantly .The rifle was a 308 Savage model 10 . Now these were only 5 shot test but were using the exact same ammo I loaded . They were all the same components loaded at the same time , stored and transported in the same way from bench to range . I ran two test with both test using a front and rear bag as the rests . First test was holding the rifle VERY tight and hard into my shoulder . That test produced something like an ES 30 with a SD 17 . The second test was done with virtually no hold or pressure on the rifle and letting it freely recoil . Just my finger on the trigger and my arms and body around the rifle but not touching to control the rifle from flying off the table . That second test ( using the exact same ammo ) just 15 min later had a ES of 12 and a SD of 5 . This was done with a 14lb rifle that has a muzzle brake so it was pretty easy to control on the free recoil part of the test I'll add this was through a well fouled barrel of at least 50 rounds and I let the barrel cool 15 min before the second test . I used an inferred thermometer and believe the barrel temp differences were 3 degrees . The reason I did the test was for a couple reasons but the main one was I was consistently having my first shots in groups shoot 10 to 15 fps slower then the next 4 and that was blowing up my ES/SD numbers . It was recommended to me by BartB that my rifle hold was the problem . At first I did not even give it a thought but one day I went ahead and ran the test just to see how much rifle hold effects velocity . Boy was I surprised , I'll add that the test with the tight grip also averaged a higher velocity as well . It was not much but was recordable . This test changed how I shoot , really because how you hold the rifle is a huge factor on your shooting .
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December 16, 2017, 02:27 PM | #45 |
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While its no nearly as fact driven as MG, I had one of my best shooting days in come really cold weather.
Ie. lots of layers and easier to let the rifle free recoil. Bart B made that observation a number of time and I agree, consistent hold is one of the bit key item.
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December 16, 2017, 02:53 PM | #46 |
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Unclenick:
This is not being argumentative let alone for argumentative sake. Solid data which I have learned to pay attention to (from my work) I have two temperature of the paint on Templiaq, 750 and 800. Templiaq sent me two more when I had issues with the 750 melting before the 800. Same result. Timing wise with a very precision setup for the case in the coil same height, same mfg cases. I am not a metallurgist, I do have a lot of mechanical experience as well as tech work with electronics, relay logic, power systems. When I have encountered a disagreement in data, I go back and check and test. When it holds consistent as this did I won't use it (maybe as a ballpark guide). The Annie is settable down to tenth of a second, the 800 was clearly taking more time to melt than the 750. I eliminated error as best I could with an entire different bottles of both the 750 and 800. So its a bit of Kentucky windage and shooting low rather than high. I have made more than one mistake in my work when I did not believe the data I collected and went off in the wrong direction. I pay attention to those details as they are always very relevant. I have had a few of times of the factory techs telling me I was wrong, but when the evidence says otherwise, you throw the mfg out. Happy to get ideas, but at this point I don't know where to go.
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December 16, 2017, 05:46 PM | #47 | |
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Also, as the temperature increases, heat is being lost to air faster, slowing the rate of temperature increase, so you'd expect the 800 to melt second and to take longer to melt. But if it didn't go that way, you have an interesting puzzle on your hands. One factor with all PCM's (phase change materials; including waxes) that go from solid to liquid (melting or thawing) or from liquid to gas (boiling or evaporating) or from solid to gas (sublimation) is that they have not only to hit certain temperatures to change phase, but to will tend to stall the rise in temperature while they absorb enough heat to complete the change of phase (in this case from solid to liquid). The amount of heat such a material has to absorb to make the change is called its enthalpy of fusion. A pound of ice, for example increased in temperature about 2°F for each Btu of heat absorbed, then at 32°F it has to absorb about 143.5 Btu's to convert to liquid phase, and then, in liquid form, it heats 1°F/Btu absorbed. If you measure the temperature of the center of an ice cube in a glass sitting in room temperature air, it first rises to 32°F, stays there until it melts, then the newly melted water temperature starts to rise again, but only half as fast just above the melting point as the ice was doing just before reaching the melting point. Waxes are PCM's, too, but often not highly pure. Alkenes (paraffins) will need anywhere from about 40 to 100 Btu/lb to melt, depending on the purity of the carbon chain lengths in the material. And, in impure form, instead of holding at exactly one temperature as they melt, they melt over a range of temperatures called the slush zone. So it wouldn't surprise me if a crayon labeled 750 actually started melting at 730 and didn't finish until 750, or some such range. It wouldn't surprise me if, due to differences in purity or in impurities, such as the coloring material, one had a lower enthalpy of fusion than another, affecting how long they needed to be exposed to a given temperature to melt. If you let two waxes come into contact, you will get a mix at the interface that has an even wider slush zone and may confuse the exact melting point. Lots of trouble to get into, and because of the timing issues for different enthalpies or for the exact compositions having different thermal effusivities (a measure of ease of heat transfer to the wax from the metal surface it is on) or different thermal diffusivities (a measure of the ease of heat spreads within a material), it is possible to have the two appear to work perfectly if you heat the work very gradually, but appear to be off or even reversed if you heat the work quickly. If the problem is with the latter, then the indicators may simply be unsuitable for any but slow methods of case neck heating. It might then be better to calibrate by coating each neck with candle soot to maximize IR emissivity (a lot of 'x'-sivities in this topic) and use an IR thermometer. On top of all that, since the metal has to change its grain structure and some of those changes are time-dependent at any given temperature, I'm not convinced we don't need to hit a higher temperature when heating at very high power for 0.25 seconds than we do when heating for 2.5 seconds with less power, and I don't know what those temperature differences might be. And they may change with the alloy being used. I think that's what the AMP annealing people are getting at. Their finding they need different times for different amounts of brass mass and different alloys and find measuring the hardness they get the only way to be consistent with the results. As a friend of mine like's to say, "Oy vey Maria!"
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December 16, 2017, 09:21 PM | #48 |
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Yes, the 800 deg melts before the 750.
A good 2/10 of a second. Settings are in the 2.1 second range so its a significant percentage the wrong way.
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December 17, 2017, 09:35 AM | #49 |
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Ok, so I was checking cases last night. 46 rounds was probably 50 to begin with. 30 Lake City 14 and 16 Lake City 12. The 14 measured 1.626 to 1.6305. The 12 all measured between 1.6215 and 1.622. These were all shot with my DPMS Gen II 308. This mirrors my earlier measurements in a previous post. This came to light because my annealing machine has different settings for different brass from Lake City. I used to segregate cases only by Lapua and everything else. If nothing else this convinces me of the necessity of sorting brass. My Lapua unfired measures 1.621 to 1.622. When I resize it all comes down to 1.6205 to 1.621. I am resizing the 14 by .o10 to .005. The 12's I am not changing much at all. There is some sizing just no bump back. This was consistent over all the cases. I came up with the setup I am using by using the Lapua and in effect going back to stock length. On one further case I measured before body sizing I measured total length and it grew by .003" after resizing. Before annealing I would have trouble bumping these cases back to where I wanted.
Ok now the question Is the 14 expanding to my chamber and the 12 not expanding? The dies are doing their job. I feel the 14 brass is definitely being overworked. I got the brass as cheap pulled brass primered and never fired. I thought Lake City was ok. Anyone got an explanation? |
Tags |
annealing , body sizing , neck sizing |
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