As a background, I have been reloading since '69, and I reload for all my rifles, handguns, and shotguns. On the rifles and handguns, I separate my cases between those I use for hunting only, and those for practice. My 556 and Grendel have not been a problem. However, I recently ran into a problem with my 7mm Valkyrie practice cases. Some of the cases will not resize and set the shoulder back and chamber properly. the base case is 6.5x47 Lapua and they are 2 years old. I annealed the cases in 2/15 and 2/16, but I don't know how many times they have been fired since the last annealing. Out of a box of 45, I have 23 that sized OK after setting the die a little deeper. The remaining cases would not chamber in my rifle. So I thought that they needed annealing. After annealing the remaining 22 caes, and resizing, only 4 would chamber. I use Tempilaq for temp control. Thinking I may not have annealed enough, I annealed again, giving them an extra second under the torch. I again resized and tried to chamber the brass to no avail. I measured headspace before and after sizing, and the cases showed little, if any, change. I don't have any split necks, case stretching, chewed up rims or loose primer pockets. My load is 38.5 gr of Leverevolution behind a 140 gr SGK, with a Rem 7 1/2 primer. The last time out, I ould only chamber 4 rounds from this box. I shot a 1.93" group, with the first round out of a cold clean bbl being a flier. The remaining 3 rounds grouped at 0.797" at 200 yds. So what is going on here?
I need help with resizing
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LB:
Sure -- you annealed the brass, thus ruining it.
I size 6.5 X 47 Lapua down to 6 X 47 without annealing, shoot the brass eight or ten times, trim it and shoot it eight or ten more times. So far I have used the same brass in two barrels (both were made using the same reamer by the same barrel maker) and have yet to lose any due to cracks or opened primer pockets.
I would only anneal brass if I had to use the brass as a basic brass to make a completely different cartridge. It isn't needed to go from 6.5 up to 7mm any more than it is needed to go from 6.5 down to 6 mm.
Chalk it up as a loss, get more brass, take one and lube it up and run it through your 7mm die and if it chambers easily, go for it.
LR55
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If annealing is bad, then why does Lapua anneal at the factory? The brass is not so hot that I cannot take it out of the socket with my bare hands, and quench it. Go to 7mm Valkyrie on facebook for more questions and answers.Life is too short for cheap rifles, cheap bourbon, or cheap women.
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Originally posted by llamaboy View PostIf annealing is bad, then why does Lapua anneal at the factory? ...
Answering the question: Note LR19955's exception to his advice to not anneal -- when one is going to a completely different bullet diameter, annealing may be advisable.
Case manufactures generally start with a stub of brass and run it through a series of dies going from a solid cylinder to the finished case. That means that they must anneal several times to keep the brass from fracturing.
So, the last anneal relieves some of the cold work in the final sizing and helps make neck tension more uniform.
Attaining a consistent anneal from case to case can be challenging for us amateurs, so, the advice LR gives is definitely consistent with my own observations.
The rest of this post is for those of us who have not been reloading for nearly 50 years:
The primary reason for annealing is to increase the number of shots one can get before the necks start to split. As LR has pointed out, one can get a lot of shots before that happens.
We can't do much about case stretch near the base which will cause separations that may leave the front 3/4 of the case in the chamber. Yes, it happens and is a PITA to get out unless one has done it a few times with the right tools and penetrating oil.
The cause for premature neck split is excessive sizing between shots. One sees this most frequently in straight wall cases where one needs to bell the mouth to accommodate bullet seating.
Should one be worried about that in a bottle neck case, then the solution is to make sure the neck sizer and expanding plug are harmonized to result in just enough cold work to be sure the resulting neck tension is uniform.
Some bolt guns will be quite happy with no full-ength sizing between shots. That keeps stretch to a minimum.shootersnotes.com
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Originally posted by llamaboy View PostIf annealing is bad, then why does Lapua anneal at the factory? The brass is not so hot that I cannot take it out of the socket with my bare hands, and quench it. Go to 7mm Valkyrie on facebook for more questions and answers.
I wouldn't buy brass that hadn't been annealed at the factory. It doesn't need any more annealing is what I am saying. When guys start to mess with perfect brass (Lapua), they normally end up ruining the brass.
You annealed it three times too many. The first two times weakened the brass but the brass was able to overcome the damage. The last time you pushed something over the edge and the brass no longer sizes down properly.
I have annealed cases but it was because the change was radical. Making 577 / 500 cases out of 577 basic brass is an example. That is a mammoth change in dimensions and without annealing I would have folded the shoulders and necks. The 577 basic brass was also very thin compared to more modern cartridges.
I simply never had a problem necking down or up a size with even the thicker brass like Lake City. If it works with your 7mm without having to anneal, why not go for it?
LR55
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You didn't ruin the brass by annealing it if it didn't collapse at the neck when you sized it.
I would check the cases that won't chamber by measuring just above the case head with calipers. Sometimes that portion of the case expands and is not addressed when resized. Compare that dimension with ones that do chamber and see if there is a difference. I had that issue with a 6mm Remington and got a small base die to size that part of the case on those that had been fired multiple times and were now refusing to chamber.
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Originally posted by 37L1 View PostYou didn't ruin the brass by annealing it if it didn't collapse at the neck when you sized it.
I would check the cases that won't chamber by measuring just above the case head with calipers. Sometimes that portion of the case expands and is not addressed when resized. Compare that dimension with ones that do chamber and see if there is a difference. I had that issue with a 6mm Remington and got a small base die to size that part of the case on those that had been fired multiple times and were now refusing to chamber.
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Originally posted by llamaboy View PostIf annealing is bad, then why does Lapua anneal at the factory? The brass is not so hot that I cannot take it out of the socket with my bare hands, and quench it. Go to 7mm Valkyrie on facebook for more questions and answers.
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It might be part of your annealing process (and after more thought, shooting process as well). Non ferrous metals react opposite of ferrous (magnetic is the quick way to remember). Heating and rapid cooling of non ferrous metals softens the metal, and slow cooling makes them harder.
With steel, if you heat it and quench it, it gets harder and harder each time, and more brittle each time. Brass and brass alloys will get softer with rapid cooling, harder with slow cooling...and brittle. Taking a fresh fired case and putting it back in a shell holder, case mouth down, insulates it to a point, slowing the cooling.
The finer points of temperature the metal reaches and cooling rates I don't know. At some point you are adding spring/memory properties to it. Dredging this up from highschool metal shop. We did not get into work hardening on anything other than ferrous metal (cold hammer steel and you get close to the same end result as heat and quench). I am wondering if your entire brass life process is getting some of that spring/memory property added to it and is refusing to be sized.
This may have absolutely nothing to do with the issue at hand and should be filed with other useless info.Sticks
Catchy sig line here.
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The annealing process if done correctly should/will not harm brass, the key is not to over temp the brass causing a chemical change. Multiple annealing's should have no ill effects... if not over temping. I only use automated equipment to maintain consistency and temperature. I have some 6mm x 45 cases with well over 40 reloadings/annealing. One reason people do this is to have a uniform neck tension. You can often feel the variations in neck "stiffness" in the form of resistance when seating bullets on cases with necks of varying degrees of hardness.. I would never anneal by hand as a single over temp would vaporize the zinc leaving only copper and ruin the case (by denaturing the brass).
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From what you said about your annealing safeguards, that is not the problem. My question is did you Anneal because you were seeing spring back from sizing or just hoping to extend Brass life? The fact that you only got 4 rounds to chamber in a box is a cause for concern to me. Were these hot loads? How are you bumping the shoulder? Are you using a shoulder set comparator for assessing sized headspace and setback and potential spring back after running through a sizing or using a chamber test (i.e. Does or does not chamber..). Also are you trimming cases as per your prep? I have one bolt gun that I have to be very diligent with case length or I get I inconsistent chamberings (regardless of how many thou's I set the shoulder back). Length, shoulder setback, or COAL most likely the culprit.
Annealing is (generally but not always) a good practice if done correctly. I track my loads after annealing and have found that with most of my bolt guns shoot the toughest groups the 3rd reload after annealing. Remember, because your Load development most likely happened under a condition where your Brass was/is partially work hardened, unless you check neck thickness you will most likely have variability in neck tension amongst your rounds...especially directly after annealing where the Brass is more mallable and has less "memory/spring back" from being work hardened. If you do anneal, depending on the die used, either go to a carbide expander ball (redding) or polish the expander ball to prevent pulling the shoulder up upon dragging the ball back through annealed Brass.
Last question, are you FL Sizing/using bushing die to set shoulder back, or sizing for a single gun and neck sizing or using a body die the. Following with a collet die to reduce runout?Last edited by CMoney; 04-30-2017, 05:10 PM.
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