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.30 Carbine crimp

Discussion in 'Handloading and Reloading' started by 06Shooter, Jul 4, 2011.

  1. 06Shooter

    06Shooter Member

    I just began loading my first 30 carbine (first in 20+ years anyway) and have a problem. The seated bullet is easily pushed into the case. The obvious solution would be to crimp, but (a) my dies don't crimp which seems odd if it's typically necessary (b) my 29 year-old Lyman book (46th edition) says "This cartridge headspaces on the mouth and case length is, therefore, critical. Never trim cases shorter than the trim-to length shown and never crimp bullets."

    I know I've read about others on this forum crimping 30 carbine as though it's routine, so what gives?


    HOWARD J Well-Known Member

    Are you using a Lee seating die that will not tighten the case around the bullet?

    Get a taper crimp die--that will tighten the case around the bullet--it will not hurt headspace.
  3. 1KPerDay

    1KPerDay Well-Known Member

    I assume you're full-length sizing, right?
  4. 06Shooter

    06Shooter Member

    I'm using RCBS dies, and yes, I'm resizing full length. It just occurred to me that maybe I'm flaring the mouth too much. I think if I back off, then the seated bullet should stay in place.
  5. res45

    res45 Well-Known Member

  6. Walkalong

    Walkalong Moderator

    No amount of crimp can overcome poor neck tension, especially on cases requiring no more than a slight taper crimp for dependability. Your sizer is too large, or your expander is too large, or both. It is possible you are flaring/expanding too much, But we cannot tell from here. First try flaring as little as you can and still start the bullets well. If that does not cure things, try skipping the expander and see if you get adequate neck tension. If you do, polish down the expander. If you do not, you need a new sizer. RCBS will replace it for free. Adjust the seater to give a slight taper crimp. .002 or less.

    HOWARD J Well-Known Member

    After you full length resize your cases ( this will remove the primer) ---remove the
    expander-decapping rod including expander ball.
    Then run your case back into the die about 1/2"
    Now try seating your bullet--see if it is tight.
    Let us know.
    Last edited: Jul 4, 2011
  8. ErikO

    ErikO Well-Known Member

    What about running shells through a round of corn starch fire sizing? Fire-sizing should correct the brass' neck issue or am I wrong?
  9. 06Shooter

    06Shooter Member

    I had a chance to take another stab at it this evening and again failed.

    My carbine die set is unlike any other RCBS 3-die set on my reloading bench. Each is stamped on top, #1, #2, and #3, and each also has the number 76 which could be the year of manufacture. I inherited most of my equipment, including this set, from my Dad so I don't know anything about the origin of this set. I know he wasn't reloading yet in 76, but that means nothing as he might have gotten it at a gun show.

    Anyway, die 1 is the FL sizer, die 2 decaps and flares, die 3 is the seater. I tried two new approaches tonight, both failed. Before each, I began by using the seating and sizing dies to remove the flare previously applied to my cases.

    First, I seated a round to an OAL of 1.680, then removed the seating plunger and lowered the seating die a bit more. The result was the same. I repeated this, lowering the die a bit more until it finally did create a visible crimp, yet without too much force I can push the bullet into the case. I'm convinced that this die simply does not crimp and I had just reached its maximum limit. The point at which this occurred, the die was as low as it could go without interfering with the shell holder.

    Second, I seated a round, then ran it into the sizing die, hoping to squeeze it a bit (taper crimp?) but again failed.

    I'm at a loss. I may just have to dish out for a set of new dies ($70?!?), but really don't want to, especially since I don't do much with my carbine. I'd be grateful for any wisdom you can offer.

  10. barnetmill

    barnetmill Well-Known Member

    I paid $20 for my carbine in the early 1960's from the DCM (Department of Civilian Marksmanship). In the past I always used the then cheap herters dies and never had a problem. Those dies really sized that case. You might want to invest in a set of dies from another source. In succeeding years I have gone to other calibers and have not loaded .30 us car in years, but when I shortly retire I will go back to it.
  11. FROGO207

    FROGO207 Well-Known Member

    I am using the Lee dies and they work great. Size/decap-first die, expander-second die, seater/taper crimp-third die. This progression is easier to use than yours IMHO and if you do not want to expand the neck I just don't use the expander die step. I can't see how your setup would decap without expanding the neck. This is necessary with lead bullets but not needed with most jacketed bullets that I use. I would just buy a new set of dies or at least a second expander button that I could turn down for the smaller diameter FMJ bullets. YMMV
  12. Sam1911

    Sam1911 Moderator

    06Shooter, go back and read Walkalong's post (#6).

    This is a neck tension problem, not a crimp problem. The tension of the neck of the case is what should hold the bullet firmly, not the crimp. The neck of the case, fresh out of the sizing die, should be tight enough that inserting a new bullet very slightly sizes the brass back up as it goes in. A friction or "interference" fit.

    The crimp is just to remove the belling of the mouth and maybe a little "belt-and-suspenders" grip on the bullet.

    This is likely what is happening: The sizing die is not squeezing the brass down tight enough to grip the new bullet.

    (Straight-wall cartridges like the .30 Carb. don't usually have an expander ball on the de-capping pin.)

    As a test, do ONE step: Size a case. Then remove the case and try inserting a new bullet. It should be noticeably difficult, if not impossible, to seat a bullet by hand.

    If the bullet won't insert by hand, try seating it with the seating die. Don't bell the case first, and don't worry about crimp.

    Is the bullet firmly held now or can it be easily driven into the case? If the bullet is still too loose, your resizing die is not sizing down far enough. You can replace just that one die and be good to go. (I'd recommend just ordering that one die from Lee for about $15. It won't hurt a thing to continue using the rest of the dies in your set.)

    If the bullet IS tight after this test, then you may be belling the case too much -- but you'd have to be belling it WAY too much, I think, to cause this problem.

    Again, the crimping step should be just removing the belling and maybe putting a hair more squeeze on things -- Like Walkalong said, maybe 0.002"
    Last edited: Jul 7, 2011
  13. greyling22

    greyling22 Well-Known Member

    if you do decide to buy new dies, my lee dies were around 30 bucks and they work fine.
  14. Smokey Joe

    Smokey Joe Well-Known Member


    06 Shooter--I have a similar set of RCBS dies, only mine are vintage 1971. (Yes, the "76" on yours is the year of manufacture.) Got mine @ a gun show, too. I've been loading since before 1971, but started with .30 Carbine only just recently.

    My #3 die, which calls itself the "seat" die, also removes any bell-mouth that #2 put into the case. It also imparts a taper crimp around the bullet.

    I haven't had any issues with loose bullets in the .30 Carbine ammo I've loaded with this die set, which would seem is the same setup as yours. :confused:

    Either you are doing something 'way wrong yourself, or your die is defective. I can't figure what you might be doing wrong from your description, and RCBS has been making dies that just plain WORK, since they started, so I hardly think it's the die's fault either.

    A call to RCBS customer service might very well be in order.

    Hope you find out SOMEthing, and please keep us posted! Good luck on this one! :)

    ETA--Had another thought: What is the diameter of the bullets you are loading? Are they truly .308"?? Not just a nominal .308 because it says so on the box?? The one time I had trouble with loose bullets (but not with .30 Carbine!) I discovered that some manufacturers make their bullets a smidge smaller than other manufacturers. Had to modify my case neck expander so the necks were a thousandth or so less in inside diameter--Problem solved. With the .30 Carbine I wouldn't modify the die, I'd just find a maker of a slightly fatter bullet, if I had that problem (The carbine doesn't seem to care much, what kind of bullets nor what maker, you are loading--Mine at least shoots all I've tried, just the same.)
    Last edited: Jul 7, 2011
  15. 06Shooter

    06Shooter Member

    Smokey Joe, thanks for the additional info. I'm 99.9% certain that the problem lies with the operator and not the equipment. A couple friends here have pointed out that it must be a sizing problem, so I'm going to recheck the sizing die at the first opportunity and hope that it can be lowered a smidge. Gotta give a fellow the 2nd degree tonight, so it may be Friday night before I can get back to my bench.

    To add insult to injury, the rim on my Quinetics bullet puller's chuck gave out, so I now have two dozen of these faulty carbine rounds waiting to be pulled and restarted.

  16. 06Shooter

    06Shooter Member

    I forgot to mention, the bullets are Hornady #3015, so I expect the diameter truly is .308. I've never had reason to question Hornady's QC.

  17. Smokey Joe

    Smokey Joe Well-Known Member


    06 shooter--Nothing wrong with Nosler's QC, either, but their .308 Accubond bullets for my .30-'06, and come to think of it, also their 8mm Accubonds for my 8mm Mauser, are smaller in diameter than the corresponding Sierra Gamekings. (And I'm not impugning Sierra, here, either!)

    I had been loading Sierras in both of the above, no problem, and then when I tried the Noslers, I started getting loose bullets in the finished necks. For both cartridges, I neck-resize with a Lee Collet die. Polished the mandrel of the Collet die down about a thousandth--Bingo! problem solved!

    Would advise you, get a nice accurate caliper, and actually measure those bullets. Also measure the i.d. of your sized cases.

    To check on my theory, I just measured a so-called .30 cal. Accubond. It measured .308" MINUS a smidge. Then I measured a so-called .30 cal. Sierra Matchking. It measured .308" PLUS the same sized smidge. (I don't have any Sierra Gamekings in .30 cal. to hand.)

    I realize the above measurements are hardly scientific--it's the best I can do with my equipment; have never had occasion to obtain a micrometer. BUT: it illustrates what I'm driving at: Nosler Accubonds run smaller than Sierras.

    Therefore, I'd urge you to actually measure the bullets you are using. You may very well be dealing with a bullet-diameter issue here.
  18. dogrunner

    dogrunner Well-Known Member

    Loaded many, many thou's of .30c........mostly (nearly always!) with surplus GI. Some of that stuff has apparently work hardened over the years and I'd occasionally get a round that'd let the bullet seat OK, but would not produce a firm hold......I do not recommend a standard roll crimp with this round....my solution was at first a taper crimp from Lee.........that gave only so-so results. Finally picked up one of their fc dies and solved my problem......now, if I wasn't so picky cheap I'd've just tossed the brass, but I have a LOT and it'd involve a LOT of pickin',,,,,,,plus like I said I'm picky cheap, I guess. I load that stuff on a Dillon 550 and that die solved a lot of double checking & so forth.

    Anyway, 99% of my issues were resolved with that die and as cheap as it is it's worth a try.

    I'd add that I shoot cast bullets almost exclusively and I did consider upping my sizing die few thou. to deal with the problem.
  19. 06Shooter

    06Shooter Member

    Ah HA! I just noticed on the box that the diameter of these bullets (Hornady #3017) is .3075". I wouldn't expect 5/10000 to make a difference, but maybe it does. Why on earth would they be .3075?
  20. FROGO207

    FROGO207 Well-Known Member

    That right there would make a loose fit with standard sized dies. Do you have even a regular 30 cal bullet (for 30-06/308) that you could try fitting into a sized:neener: case the same amount and then check the tension? I am betting you will find a BIG difference.

    I just went and measured mine. I had 3 different ones, Hornaday,Remington and a generic all 110 grain FMJ/Jacketed. All measured .308 + almost nothing.
    Last edited: Jul 7, 2011

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