Accuracy vs Crimping

Discussion in 'The Ammo & Reloading Forum' started by steve4102, Oct 1, 2012.

  1. steve4102

    steve4102 Former Guest

    Joined:
    Jan 27, 2006
    Messages:
    2,759
    Location:
    Minnesota
    I know I have posted my accuracy tests using the Lee Factory Crimp die in the past, so I hope you don't mind if I do it again.

    I purchased a K of Midsouth's 55gr Varmint Nightmare JHP bullets for about $90.

    I decided to test this new to me bullets in my Colt AR both with a Lee crimp and without. My crimp is what I call a Med-Light.

    I chose Win 748 as it has worked well for me in the past with 50-55gr bullets.

    I fired five rounds at each target allowing the barrel to cool between each five round group. This is the first set of groups.

    [​IMG]


    I then fired five shot groups from the bottom up starting at 26.5gr and working up the target to 25gr. I did not let the barrel cool at all. The only down time between rounds was loading the mag.

    [​IMG]

    As you can see these bullets shoot damn good for cheap bullets and you can see that the rounds crimped with the LFCD outperformed the non crimped rounds.

    26gr Crimped is a winner in my book.
    Last edited: Oct 1, 2012
  2. JLA

    JLA Well-Known Member

    Joined:
    Feb 26, 2007
    Messages:
    18,268
    Location:
    Heart Of Texas
    And you have a real winner with 25.5-26 gr W748 and those bullets. ID personally call 25.8 my load.

    Good thread steve. :thumbsup:
  3. woolleyworm

    woolleyworm Active Member

    Joined:
    Feb 23, 2009
    Messages:
    4,945
    Location:
    SW Fort Worth
    I'll second the thumbs up! Great visual documentation and clear results. The LFCD is worth the extra effort.
  4. aa1911

    aa1911 Active Member

    Joined:
    Dec 12, 2010
    Messages:
    3,211
    Location:
    Pacific Northwest
    thanks for the good write up!

    isn't 748 the same powder used in military ammo for the 5.56? thought I read that somewhere recently.

    Hodgen has their new .223 specific powder out now too, supposed to be even cleaner burning and 'cooler'/easier on the barrels. but the military stuff burns just fine as far as I care.
  5. myfriendis410

    myfriendis410 Member

    Joined:
    Mar 30, 2011
    Messages:
    603
    Location:
    Lompoc California
    What was your distance?

    A crimp can certainly improve consistent velocity numbers which (usually) make for a more accurate load.

    Nice workup.
  6. steve4102

    steve4102 Former Guest

    Joined:
    Jan 27, 2006
    Messages:
    2,759
    Location:
    Minnesota
    Sorry forgot that, 100 yards
  7. JLA

    JLA Well-Known Member

    Joined:
    Feb 26, 2007
    Messages:
    18,268
    Location:
    Heart Of Texas
    As far as I understand milspec 5.56 ammo is loaded with bulk grade W748. It was developed for longer barrel life in the M16s and increased performance.

    And that CFE223 your are referring to. Awesome stuff. it prevents copper fouling. Burn speed is close to W748.
  8. bluesea112

    bluesea112 Active Member

    Joined:
    Nov 20, 2005
    Messages:
    1,336
    Location:
    West, TX
    I have always heard that crimping is better for accuracy, but it is nice to see it proven on paper.
  9. Bindernut

    Bindernut Well-Known Member

    Joined:
    Oct 24, 2007
    Messages:
    3,152
    Location:
    ND, USA
    Very nice documentation Steve!
    Just out of curiosity, but I notice how on-target the groups are. You didn't have any major POI change through that range of charge weights? I haven't ladder tested my .223 yet.

    To date, I haven't messed around with the LFCD in any caliber.
    I have picked a couple calibers up when they've been on sale but I honestly have never threaded them into a press yet. :eek:
    I'll have to put forth a little more effort to give em a try some time.
    I do use a crimp on any cannelured bullet for my rifle loads, but just what I get from the particular brand seating die that I'm using.
    Last edited: Oct 3, 2012
Similar Threads
Forum Title Date
The Ammo & Reloading Forum Does your SD ammo match your developed reload in recoil/accuracy? Jul 24, 2014
The Ammo & Reloading Forum Accuracy versus Speed versus Cost May 24, 2014
The Ammo & Reloading Forum Velocity Does'nt Mean Accuracy A Lot of the Time Jan 8, 2014
The Ammo & Reloading Forum lee auto disc accuracy concern Jun 9, 2013
The Ammo & Reloading Forum More revelations in consistency vs accuracy May 15, 2013

Share This Page