To Crimp, or Not To Crimp... That's a good question!

Discussion in 'Ammunition & Reloading' started by Brother_COM, Sep 25, 2011.

  1. Brother_COM

    Brother_COM New Member

    Guys I'm new to reloading and I need some help with whether or not to crimp.

    Background info: I'm reloading .223 cal for my Mini-14. The Sierra 22 cal bullets DO NOT have a caneluer. <spelling?>

    I DO have a very nice 223 LEE Pacesetter Factory Crimp Die Set

    I've been told that I "have to crimp because the other bullets in my magazine MAY slide in their cases as I'm firing." First off, with the die I have is this even true???

    So do I need to crimp?
    What will it benefit me?
    HOW MUCH of a crimp should I use?

    Thanks in advance for the wisdom you'll share,
  2. Trez

    Trez Well-Known Member

    I dont own a .223 but..
    If the bullets dont have a cannelure, I wouldnt crimp them... The only time you have to crimp is for tube fed mags. I was crimping Arisaka rounds with cannelures (To dupicate the military rounds) and was told it was unnecessary... Most times just the neck pressure will hold the bullet in place..

    Im not sure you can crimp bullets without the cannelure.... But I could be wrong?

  3. Txhillbilly

    Txhillbilly Well-Known Member

    There are +'s and -'s with crimping bullets.

    I rarely ever crimp any of mine,but I set up my sizing dies so that the necks have a good grip on the bullets.
    Now using Lee dies,they all do somewhat crimp with the seating dies,but you can adjust it by turning the dies in or out of the press.
    If you want a good crimp,buy a Lee factory crimp die,I use them on several of my loads where the bullets are really stretched far out of the case.

    Crimping will increase pressure,which can be good and bad.
    If I chronograph a load,and it is slower than it should be,I'll increase the crimp a little.In most cases,it will increase the FPS of the bullet.But if I start seeing pressure signs on the primers or the cases,I'll back the crimp off a little.

    If you set your dies up correctly,you don't really need to crimp the bullet much,unless it's just something you want to do.
    It also depends on the type of bullets you are loading.If you are expanding the case mouth for flat base bullets,then a slight crimp will be needed. I always chamfer my cases,so that's only an issue on pistol loads for me.
  4. Jake15

    Jake15 New Member

    I crimp everything, especially loads used in semi-autos because they tend to handle ammo roughly, as opposed to a bolt action where you can gingerly cycle the action. Crimping does increase the pressure, but if your crimp die is set up right it will help to even out the pressure of a batch of loads, and I have the same die set but for 7mm rem mag, and the crimp die easily crimps bullets without a cannalure, as a matter a fact the bullets I'm using now don't have a cannalure, and I had to pull some and the factory crimp die had actually made its own groove when it was crimped!
  5. OldManMontgomery

    OldManMontgomery Member

    Bullet movement in recoil...

    Depending on the recoil level of the rifle in question, bullets can move fore and aft, bumping the bullets deeper into the case. This can be solved by increasing neck tension or crimping. However, it is poor practice to use a crimp in place of proper neck tension.

    Semi-automatic handgun bullets will also 'seat deeper' bouncing around in a magazine, but it's not as common.

    Revolver bullets pull themselves in heavy recoiling revolvers. The revolver acts like a big kinetic bullet puller. This usually only happens with heavy bullets, heavy loads and not quite enough crimp.

    I find at least a gentle crimp in combination with a tight neck on most rounds gives better ignition.
  6. anm2_man

    anm2_man Member

    Every semi auto round that is fed from a magazine should be crimped. They take a beating being inserted into the chamber (envision a double stack magazine - left, right, left, right, etc). Now with a bolt gun, for better accuracy, No crimp required.

    As far as not having a cannelure, don't worry about it. I always have crimped my 9mm loads using Berry's plated bullets. The Lee factory crimp die does a great job.