GAP 10 - Crimp?

pkt1199

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I will be loading for a GAP 10 someday when the wait is up - but was curious if those doing so already are crimping?

Also if anyone has input on a good die set for 6.5CM I'd appreciate it.

Thanks!
 

poison123

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    Nope. Never crimped my .308 and seriously doubt you would ever need to on the 6.5cm either.
     

    T J

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    I don't crimp for my AR in .243win either, I have yet to see a oal change.


    t
     

    JGorski

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    No, I dont crimp my 6 Creedmoor, never crimped the 6mmREM loads I loaded for me and my dads Rem autos either.
     

    pkt1199

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    Thank you all for the info. I wasn't sure what the status-quo was on it.
     

    Creature

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    I have banged my head against the wall with this issue as well. In one regard the bullet can be pressing back into the case increasing pressure OR the crimp can increase neck tension and raise pressure. I called Sierra and Redding to ask about this issue and they said yes, crimping can cause an increase in pressure, but it's consistent. The problem with not crimping is that not every round will press back into the case. Depending on how the tip strikes that feed ramp. They said this is a less consistent variable compared to crimping. I don't put a real heavy crimp on mine.
     

    Fredo0621

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    How often do bullets really get pushed backed into the case? Are you air dropping your handloads from a plane or ride in a Humvee on non- paved roads? I just never seen that happen in "normal" conditions. Just load them without a crimp and shoot.
     

    Name Enough

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    Disagree here. I just posted I crimp all my loads for gas guns. Military pattern rifles have violent actions to insure reliability under harsh field conditions. Bullet set back can cause a catastrophic failure and I like my face just the way it is. In my experience crimping will not effect accuracy or veloicity to any measurable extent. Some experienced reloaders will tell you that you will actually improve accuracy and consistency.
     

    r50140

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    GAP built me a 308 upper about 8 years ago. I have been using a Lee factory crimp on all of my hand loads for this gas gun. A actually use the Lee factour crimp on all of my gas gun reloads. I'm convinced the light factory crimp improves accuracy and consistency. Your milage may vary.
     

    sentry1

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    How often do bullets really get pushed backed into the case? Are you air dropping your handloads from a plane or ride in a Humvee on non- paved roads? I just never seen that happen in "normal" conditions. Just load them without a crimp and shoot.

    Using new 55 gr FMJs, I don't have an issue, but with el cheapo pulled bullets, without a crimp they get jammed back in the case when they hit the feed ramp. A $10 Lee crimp die doesn't make a big dent in my $ savings from using pulled bullets.
     

    dvdt

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    I had a GAP-10 in .260 and this was one of my biggest worries. I tested the crap out of it in my "field" conditions (i.e. going to the range and doing my thing) and never once saw any change in OAL. I did a lot of testing too. This is just one man's experience.

    I use the Lee Factory Crimp on my .223 AR loads. I like it so much that I plan on doing the exact same thing with my new GAP-10 in .308.

    I agree with sentry1 and r50140. It's cheap and I just put it in stage #5 on my 650.

    I'm too lazy to google LFCD for 6.5CM but I would imagine the .260 LFCD would probably work too.