GUN Reduced OAL? How much of a problem is it?

Discussion in 'On Topic' started by Emanon, Mar 7, 2010.

  1. Emanon

    Emanon Active Member

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    I had heard that 9mm doesn't suffer as bad as other popular calibers (ie 40 and 45) so never really worried about it. Now I'm joined a new range by my house which makes me unload before coming into the facility I seem to be loading/unloading more often than I want.

    I started to mark each round with a black mark and once it has two I fire the round. Now should I continue this practice or am I too worried about it?

    I would rather not use this ammo as it isn't just WWB 9mm rounds. Yes I do try to put some of the hornady down range at times but the cost just doesn't make it efficient for me to shoot all the time.
     
  2. Thunderbear

    Thunderbear Yggdrasil's Forester.

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    Good practice for if you ever carry your .45. They'll set back after as few as two or three cycles. I have a almost a whole box of Hornady TAP rounds from having to do the same thing. Yar can explain better than I the crimping differences in 9 vs. 40/45, but IIRC the .45 is just press fit, rather than a full crimp.
     
  3. yar1182

    yar1182 New Member

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    It is largely dependent on type and charge of powder. If bullet set back (aka Shorties) can cause unsafe pressure. With that being said with factory ammo especially pistol ammo I would not worry much. You would have to set back the bullet really really far before it would get to an unsafe pressure. That and most factoryl ammo is quite tame pressure wise (at least compared to what I load it to) for liability reasons. Pistol ammo also head spaces on the case mouth and there is a good amount of jump before it hit the lands. Only real thing the bullet comes in contact with is the feed ramp and that is a defelected blow and would not really push the bullet in.

    I would say with pistol ammo you could probably feed and eject it 100 times and you would not see noticable set back that would begin to increase pressure.
     
  4. Emanon

    Emanon Active Member

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    Thanks Yar :bigthumb:
     
  5. yar1182

    yar1182 New Member

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    automatic pistol ammo is taper crimped because pistol ammo headspaces on the case mouth. Now rifle and revolver ammo can be either taper or roll crimped.

    Most factory ammo has a pretty decent crimp, though I should say you should check yours as it can vary.

    Now with 45 being such a low pressure round I really would not worry.
     
  6. Thunderbear

    Thunderbear Yggdrasil's Forester.

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    I still cringe when I pull a round that the case mouth is right on the shoulder of the round. When I get set up to reload, I'll pull the bullets and reset them.
     
  7. Keesh

    Keesh New Member

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    Like Yar says, pistols headspace off the case mouth. I've loaded/extracted carry ammo over 50 times, hit it with the calipers and there is no discernible difference. The brass gets pretty beat up after a while however.
     

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