Brass springback? Brass not sizing?

Jmccracken1214

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  • Dec 10, 2018
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    Thomasville, NC
    Have had some weird stuff going on lately. Using starline brass, most is 2-3 firings.
    I had trouble chambering some rounds recently that were 100% sized on the same die they’ve always been sized on. I checked headspace the most were either the same as once fired or 0.001 under. I adjusted my doe to size down another 0.001. Put me at 1.556-1.5565 when checked the shoulder.

    some of the brass I sized came Out 1.558...I ran it through again and it would be 1.557and some stayed the same....most Measured 1.5600 andonce sized came out 1.5565....

    Why is some of the brass not changing? It’s always annealed after every firing.
     
    One thing in reloading that is commonly ignored is dwell time. A friend described forming panels for aircraft that each cycle also required a specific dwell time to avoid spring back. This step insured a closer tolerance. I wonder if certain formulations of brass may require the same treatment. Give it a try, 3-5 seconds sitting in the die is what I do.
     
    Have had some weird stuff going on lately. Using starline brass, most is 2-3 firings.
    I had trouble chambering some rounds recently that were 100% sized on the same die they’ve always been sized on. I checked headspace the most were either the same as once fired or 0.001 under. I adjusted my doe to size down another 0.001. Put me at 1.556-1.5565 when checked the shoulder.

    some of the brass I sized came Out 1.558...I ran it through again and it would be 1.557and some stayed the same....most Measured 1.5600 andonce sized came out 1.5565....

    Why is some of the brass not changing? It’s always annealed after every firing.

    You may actually be partial FL sizing. If that is the case what you are seeing is typical. And annealing adds unknown variables it doesn't always improve anything. We're not metallurgists. Also, it is not uncommon to retire brass sooner rather than later.

    I do like dwell time suggestion when splitting hairs like this. Makes perfect sense especially when purposely softening brass cases prior to sizing.
     
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    Are you sure it's the headspace dimension? SAAMI maximum cartridge headspace is 0.003" more than minimum chamber headspace for 5.46 NATO/.223 Rem and 0.004" for 7.62 NATO/.308 Win. If you're annealing every firing, springback should be at its minimum but it also depends on whether the annealing gets down to the entire shoulder.

    It could be the body down by the case head that doesn't get annealed and does have more springback.
     
    I’ve been messing with my annealeez this morning. Running at 50% speed, I think it’s too fast. I ran some test brass on it at 40%, which had the brass in flame for 6.51 seconds. Flame did not change color which would be over annealing and the anneal mark looks better on the test brass. More noticeable than I had with my shooting brass.

    I’m wondering if I’ve just been a dumbass and under annealing the entire time lol. That would make sense right? Brass hardening and not sizing consistently ?
     
    What don't you just set the die up according to the directions and see what you get. You need a normal benchmark to start with.
     
    What don't you just set the die up according to the directions and see what you get. You need a normal benchmark to start with.
    I did that and it was a tad too much. I think ive got 2 things messing with me... 1 was annealing and the other lack of lube.

    I usually put them all in a tray and spray with hornady... I just measured all the brass and set aside the 41 that didnt size properly.. I annealed them a tad longer, and sprayed each one while holding it with the ONE SHOT lube, prior to sizing and noticed they went into and out of the die a lot easier and actually came out the correct headspace.

    Riddle me this, but shouldnt it size it, even if there is a lack of lube and the case is still pressed into the die?
     
    I know according to the directions it bumps too much but do you have the same level of bounce back? If not, than size a little closer until you start getting the bounce back. You may think you are sizing the shoulders .001 back when in fact you are partial resizing, which some people use rather than neck size.

    I don't anneal but I really don't see any reason to anneal a cartridge that is not overbore. Like .223 or .308. I don't think it is your lube either.
     
    Riddle me this, but shouldnt it size it, even if there is a lack of lube and the case is still pressed into the die?
    I'll take a stab - Without lube the case locks up in the die and the stacked stretch in your press ram/linkage/lever give before the case does. When lubed, the case offers less resistance than any of the parts subjected to load from the movement of the ram/linkage/lever.

    Probably not the case here, but always use the same shell holder. I've seen some small size variations that change how far the case moves when the ram is fully raised.
     
    I have a mec marksman coming next week. Ordered from a member here. So I’ll have to re set everything then. I’m curious to see if I notice any difference on it from my hornady single stage that will be strictly a depriming machine
     
    I’ve been messing with my annealeez this morning. Running at 50% speed, I think it’s too fast. I ran some test brass on it at 40%, which had the brass in flame for 6.51 seconds. Flame did not change color which would be over annealing and the anneal mark looks better on the test brass. More noticeable than I had with my shooting brass.

    I’m wondering if I’ve just been a dumbass and under annealing the entire time lol. That would make sense right? Brass hardening and not sizing consistently ?
    That's why the AMP is popular. You need tamplaq sticks to know temp or a temp gun.