To Crimp, or not to Crimp?

I’ve gotten 50 rounds of 6.8 Remington SPC loaded, and 100 round of .223 loaded. I have a progressive press a reader sent me a while back (a Lee, which he didn’t use anymore and wanted to get rid of), but I only have the necessary equipment to load pistol ammo with it, and the Lee progressive has a rough time with that, so I’d be worried with rifle ammo.

For rifle ammo, I’m loading on a single stage press. For practice ammo, I don’t weigh each charge, and I’ve actually found the Lee powder charger throws a pretty consistent load once you run it five or six times. I’m limited in speed mostly by press time. I do 50 at a time. My process is as follows.

  1. Run 50 rounds through the tumbler to clean off the brass.
  2. Stage them on my reloading block, after running them through the separator.
  3. Spray them with some reloaders KY.
  4. Decap & resize on the press & move to finish block.
  5. Seat the primers, move back to staging block.
  6. Adjust the powder throw, charge 50 cases, move to finish block.
  7. Check all the cases for proper charge, seat the bullets.
  8. Seat all the bullets, measuring the first few for overall length, moving to staging block.
  9. Crimp bullets on the press.

The last part I’ve heard various advice on. Some people suggest you don’t need to crimp the bullets, and that the military only does it because they have to stand up to rough handling in machine guns. When I first starting reloading, I’m pretty sure I was over crimping, which can be dangerous. But I still tend to think a light crimp on the bullet is good for firing through a semi-auto, despite the extra cycle through the press it takes for each batch of 50. What do you think? To crimp or not to crimp?

21 thoughts on “To Crimp, or not to Crimp?”

  1. Well, first it depends on the round. Those that headspace off the mouth (most rimless pistol rounds) need to be VERY lightly crimped, basically just enough to remove the case mouth flare.

    Those that headspace off of a rim or shoulder can be crimped as much as you like (within reason of course, if the brass buckles you went too far).

    One thing I did not see it your list of steps is trimming and deburing the cases, if you are going to crimp the length must be uniform or some will get a light crimp while others will get crushed into something resembling the flexible part of a straw. I’ve done it, not pretty.

    My steps are:
    1 Sort cases if they are mixed.
    2 Lube (if needed- love carbide dies!) and size and de-prime.
    3 Check, trim, and deburr cases.
    4 Tumble, this removes lube and polishes any minor neck roughness on the cases.
    5 Prime cases, I use a hand primer, be sure to check that there is no tumbler media in the flash hole!
    6 Expand and flare case mouth as needed.
    7 Set powder measure and charge cases, double check all cases after charging. Dump and do again any that look “off” either high or low.
    8 Seat and crimp bullets
    9 go shooting :-)

    1. I used to measure each case meticulously, but I’ve found with 0x or 1x fired brass, which I have an awful lot of, I don’t notice much need to trim or deburr. I came into 1000 rounds of .223 military brass (unfired) for cheap a while back and have now gone through it. I just started going through my probably 10,000 rounds of once fired .223 brass. At 2x I’ll probably trim and deburr if it’s looking like they need it. Beyond that I’ll probably just go visit a few more matches and pick up brass :)

      That brings up another question. Do you generation your pistol brass? Some folks say you can more safely go by visual inspection with pistol brass. Right now I generation just about everything, but at some point that’s going to be difficult.

      1. I probably should, but I don’t use the volume you evidently do either, all fired brass gets thrown in a coffee can or a bag at the range, brought home and dumped into a bigger coffee can until I get low on ammo, then it gets sorted by caliber (I even have a few ziploc bags of brass I don’t have guns for that got picked up at the range, figure it will get used someday) and then stored into marked coffee cans by caliber. (useful things, aren’t they?)

        I do tend to use brass to failure point myself, while priming I do my case checking as I’m looking it over for retained tumbler media, have found many rounds with splits at the mouth or bright rings near the base. These get crushed with pliers and sent to recycling (that is a gallon ice cream tub, not a coffee can!)

        I have a lot of nickel plated brass I use for defensive carry that has only been fired twice as of now. If I was into competitive shooting I probably would pay more attention to the times my brass has been fired, but even my practice ammo which have no clue how many times it’s been reloaded has had few complete failures.

        So I guess my inspection is pretty good, over 30 years and thousands of rounds of reloading rifle, pistol and shotgun ammo I’ve only had 1 case failure that stopped the gun from working, a 30 M1 Carbine round had the bases separate and leave the forward section in the chamber which I had to tap out with a cleaning rod.

        I am the worst with shotgun reloading, if it will still hold a primer and a crimp it gets used, split hull mouths and rusty ‘brass’ (I’ve had to sand the “brass” on a few hulls, evidently they are brass plated steel and not real brass nowadays) are ignored. BTW I discard any hulls that have separate base wads, only using one piece hulls for reloading. Much safer, especially how many times I reload them!

        1. Oh and I use the Lee case trimmers, they are foolproof! If it is over length it gets trimmed. Every case goes thu the trimmer whether it needs it or not!.
          A while back I bought some (supposedly) once fired and roll sized 380 brass that I found out while lightly crimping them that some were slightly different lengths as most crimped but a few were crushed, that batch was intended for defensive use but is now practice ammo as I’m not sure how each one will chamber. 50 XTP’s wasted……

  2. I don’t tend to crimp any of my rifle rounds. I generally load .223, .308, and .338 Lapua.

    I haven’t ever had any issues with bullets getting pushed back into the case by anything other than a jam or mis-feed… which would have pushed the bullet back into the case with most commercially loaded ammunition anyhow.

    I do feel that crimping does cost you something in terms of accuracy. On the flip side, for practice .223 with 55gr FMJ-BT, I will sometimes crimp if there is a cannelure for that on the bullet itself.

    At some point when I have time, I’ll probably load some .223 and .308, crimped, uncrimped, with military or commercial brass(if military is available), then immerse in water for 1 minute, 1 hour, 1 day, etc, then test fire to see if there are any misfires or other issues.

    If uncrimped ammo tends to have many more problems with misfires, I’ll consider crimping my SHTF ammo, but I still won’t crimp the stuff I load for pure accuracy.

  3. I reload for four semi auto rifles in three calilbers. I’ve never found a need to crimp any of them. The only crimp I use is on pistol rounds that I taper crimp.
    My reloading plan of assault for rifles that has served me well for over 30 years is:
    1, Tumble brass
    2, Inspect cases when setting up for spray lubrication
    3, Full length resize / decap
    3a, At this point, the cases are measured & trimmed to length & case mouth deburred / chamfered as needed.
    4, Tumble again to remove case lubricant
    5, Reprime, feeling for loose primers & inspecting for cracks etc.
    6, Set up in loading block(s) case mouth down.
    7, Charge cases with propellant & return to block mouth up.
    8, Under strong light, look down at charged cases for even powder levels.
    9, Place bullet in case mouth & seat to known depth.
    10, Place completed rounds in cartridge boxes with identification as to powder type, charge weight, bullet type, weight & primer maker.
    11, Go to range & start all over again.

    Note that my ammo is used for target shooting & all brass has had its flash hole deburred & is segregated by manufacturer. I find that the flash hold deburring does help with consistency, segregation of brass, less so. Also, every time I handle the cases, I am looking for cracks, marks, etc & throw out any that look suspicious.


  4. Test it.

    If you can’t see a noticeable difference in your groups between the crimped and uncrimped, then crimp them. I figure a little extra insurance isn’t a bad thing.

    I personally crimp all mine because I’ve never noticed a difference in accuracy. But then I’m just loading for ‘make it dead’ type practical accuracy out to 300 yards and not benchrest type shooting at 1000 yards.

    BTW, do the bullets you’re using have a cannelure?

    For brass I don’t sort by generation, but I do inspect inside each case with a borescope. I’ve found I can see an incipient head separation building *long* before I can feel a ridge with a probe or see a bright ring on the outside of the case.

  5. Crimping rifle rounds definitely, greatly, detracts from accuracy. Don’t do it. I guess I should qualify that by saying that is my experience for calibers of less than or equal to .308. The recoil isn’t enough to warrant it.

    I also have a bias against anything Lee. I wonder why anyone would just want to get rid of a loader???? I tried the Lee crimper when I was just getting started with match reloading, for the .308. I’m a scientist and always do controls, so it was obvious that crimping was a BAD idea. I have to wonder, then, about a company that still sells crimpers. And little kits with a scooper to measure powder. Sheesh.

    Walk the line at the National Championships and the great majority are using the blue machines(Dillon 550’s).

    I never liked the Hornady spray lube. It didn’t seem to really lube enough – I would still get squealing and sticking. I tried the Dillon pump spray and had much better results. It’s just lanolin dissolved in isopropyl alcohol. I even tried making some myself (which worked well) but the labor cost was more that just buying it from big blue.

    I went to Nationals shooting service rifle 4 times. I got good enough that once in a leg match, I tied Konrad Powers (multiple national championships) for score. He beat me on X-count, 476-19. I only had 15. Nobody I knew shooting across the course matches crimps.

    1. It seems like you can’t do a post about reloading without a member of the blue cult coming by to try to recruit you in.

      I kid, I kid. I know there’s a reason serious competitors use them. I got the Lee stuff because it was cheap/free. One of these days I’ll shell out for a decent progressive, but for now I’m not shooting enough to justify the cost, and with only a range out to 200 yards at the club, I can’t practice for honest to god high-power out to 600 yards anyway.

      1. The “cheap” part is why I also use Lee stuff.
        I have a Lee Challenger single stage press, Lee Hand Primer, a Lee Load All for shotgun, Lee case trimmers, some Lee dies, some RCBS dies, some Hornady, use an RCBS Scale and powder measures (1 set up with small bore and one with large bore), RCBS Case Trimmer, neck brushes and primer pocket cleaner. I also use the Lee water based lube, mostly due to it’s ease of use, just a dab on your fingers and the case gets lubed as you handle it!

    2. Can’t argue on accuracy, I’m a hunter first and a target puncher second, an inch or inch and a half at 100 yds is fine accuracy by me. 2 inch is acceptable.

      If you are shooting a lever action or any other rifle with a tube mag (dunno what it was, but I’ve seen a tube fed bolt action before, no clue why anyone would WANT a tube fed bolt action though…..) you MUST crimp fairly heavily or the bullets will be driven into the cases during recoil. even with a crimp into a grove I’ve had a few bullets get set back into the case.

  6. I think the Lee Loader kits that use a hammer are pretty cute and functional… but besides that, I completely agree. I have very few pieces of Lee reloading equipment or dies. I prefer Dillon and RCBS presses and eqipment, for the most part.

    1. These are seldom a good idea in rifle rounds. Especially if there is no actual sign of a need for crimp, such as poor powder burn, or setback of the bullet.

      The ads for Lee’s “factory crimp die” are the most deceptive in the reloading business.

      1. I have one of those Lee factory crimp dies for my 6.5×55, it will not only crimp the case but put a crimping groove into the bullet it’s self too if you want it to!

        Doesn’t take much effort either…..

      2. I’ve always been told you should crimp Heavy recoiling rounds for revolvers to prevent the possibility of the bullet creeping outward from recoil and locking up the gun as the cylinder tries to turn.

        Rifle rounds should be crimped for automatic rifles and tube fed rifles so the bullet doesn’t get driven into the case while being slammed into the feed ramp on the way to the chamber or while being slammed back and forth in the mag.

        I’ve had 30-30 rounds that were crimped into a crimping groove get pushed into their cases while in the mag. They take quite a beating during recoil……

        Also some of the newer rounds with very short necks, and thus less surface to hold the bullet in place, should also be crimped.

        Rounds for bolt actions is more a matter of preference in my opinion.

  7. Revolver and semi-auto pistol rounds, I always crimp; gets rid of the flare at the case mouth and helps make sure the bullet can’t shift.

    Rifle I do as well. I found some cartridges I got better accuracy when I do, and the others, again, I like knowing less chance of a bullet shifting under recoil.

    Some cast-bullet ammo, I’ve known people who don’t resize and do flare the case mouth just enough to let them seat the bullet, and leave it at that; this is ammo that goes into the box and is loaded one at a time at the range, so they figure it works the case mouth less and the cases last longer.

    1. Makes sense, working brass hardens it and causes cracks, so less work should mean longer case life.

      I assume they also only use that ammo in one specific gun?

Comments are closed.