1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

.308 reloading queston for M1a

Discussion in 'Handloading and Reloading' started by ScottsGT, Dec 31, 2008.

  1. ScottsGT

    ScottsGT Well-Known Member

    Just getting started reloading .308, and I'm still gathering up all the tools, brass ect....
    Decided to go with IMR 4895 powder since I can use it in my .30-30, .30-06 and I'm sure my .223 once I look into it too.
    While I was at a local fun store (Gun store for those whom never frequent them!) and I picked up a box of 100 Sierra 168 grn. HPBT bullets. Got home and noticed that there is no crimp ring on them and I read that you don't use the crimp die. Makes sense. Now here's my qustion. Can i use these in an
    M1A? I'm worried that during the loading/firing process that the bullet might be shoved back into the case causing problems of over pressure, and jamming?
    Again, I have NO experience with rifle reloading, YET.
  2. Slamfire

    Slamfire Well-Known Member

    Never, ever, ever, crimp a Sierra Matchking bullet. Ditto for Nolser, Hornady, Speer match bullets. Case neck tension alone is sufficient for a M1a. I have shot out 3 match barrels on M1a's, never saw a need to crimp.

    Crimping was done on military bullets that were going to be fed into machine guns. The feed rate was such the bullet could pop out. The military also used tar sealant.

    I have a few rounds of M852, the 168 SMK stuff loaded for target shooting. Lake City did not crimp that bullet.

    The picture below is what happens to a 6.5 SMK when you use one of those Lee Factory Crimp dies. A friend did this, used a “light” factory crimp. Sure ruined these bullets for target purposes.


    Advice for reloading for your M1a

    Buy a cartridge headspace gage. Buy small base dies and RCBS water soluble case lube.

    Size your brass with the small base die. Set up your dies with the cartridge headspace gage. Size to gage minimum.

    (It can be just impossible to small base 308 cases with some lubes, RCBS and Imperial sizing wax work great)

    Trim to length, I trim to 2.00” because it is easy to remember.

    A good safety measure is to ream your pockets to depth. Whatever you do, prime by hand, inspect each case, and make sure the primer is below the case head.

    Prime using the least sensitive primer you can find. Do not use Federals, I recommend CCI #34’s.

    For a 168 SMK, try 40.5 to 41.5 grains IMR 4895.

    Seat to 2.800” or less. I am using 2.750” right now.

    Absolutely no crimping!
  3. USSR

    USSR Well-Known Member

    Neck tension is used to hold match bullets in place. To see if you have enough neck tension, take one of your reloaded rounds and put the bullet tip against a table top while grasping the case and forcing it down against the table. If the bullet doesn't move, you're GTG.

  4. USSR

    USSR Well-Known Member


    Ah, the humanity:eek:, ruining those beautiful, sleek 142SMK's.

  5. Slamfire

    Slamfire Well-Known Member

    Just makes one cry.

    I did the same with the Lee Factory Crimp die in 308. Followed directions and "coke bottled" a bunch of 168 SMK's.

    Shot them at 100/200 yards, they did well at that distance.

    Wonder which US State they would have landed in if I shot them at long range.
  6. ScottsGT

    ScottsGT Well-Known Member

    Thanks guys. I've yet to get started since I just relaized that I have no case trimming equipment! D'OH!!! To make matters worse, Sportsmans Warehouse is out of the Lee case trimmers, Cabelas is out, Midway USA is out, Widners is out, and as are many others that I have done web searches for. I'm guessing it is a end of year inventory thing. Hoping things look better in a few days or I'm going to have to go direct to Lee and pay full list price. I know, only a couple bucks more, but when I need case trimmers for 4 different calibers, it will add up.
    Had a feeling the crip would ruin things, thought I'd ask first. I did see where I can order lower cost military style bullets off the classified board. Might get me 1K of those for plinking, and save the SMK's for serious shooting.
    BTW, what is a "Small base die" compared to a standard set of Lee dies? I've got the Lee set of three dies (progressive?) And using everything in a Lee Classic Cast press.
  7. Galil5.56

    Galil5.56 Well-Known Member

  8. Slamfire

    Slamfire Well-Known Member

    RCBS told me that their small base die will reduce the case head more (.002") than their standard die.

    I recommend using a cartridge case head space gage to set up a small base die because you can push the shoulder back too much. This will create early case head separation. This is seldom true with regular sizing dies, in fact I have had to grind material off the bottom of some regular sizing dies because they left the case too long.

    There are differences between brands, Lyman small base dies reduce my cases than other brands. Too bad Lyman does not SB dies any more.

    The attached URL has pictures of cases sized with Lee dies and a Small base.


    For any firearm with a free floating firing pin, it is a critical safety consideration that you size the case smaller than chamber size. You absolutely do not want any delay to bolt closure. If your case is fat, too long, and you have an oversensitive primer, that firing pin is tapping the heck of the primer as the bolt attempts to crush fit the case to the chamber. At the moment of bolt delay, that's when out of battery slamfires occur.
  9. ranger335v

    ranger335v Well-Known Member

    It is a shame:

    "The picture below is what happens to a 6.5 SMK when you use one of those Lee Factory Crimp dies. A friend did this, used a “light” factory crimp. Sure ruined these bullets for target purposes."

    But the cause isn't the Lee FCD die. It only does what the user adjusts it to do and those are NOT LIGHT crimps! The FCD will do anything between no crimp at all to what the photos show, it's all up to the user.

    That said, there is no automatic reason to crimp bullets for an M1 and certainly not to keep them from pushing in. It's much more likely they might get jerked out a little as they chamber.
  10. Slamfire

    Slamfire Well-Known Member

    I got "coke bottled" 308 SMK's with a FCD setting that did not even leave marks on the case neck.

    You only find out after you ruin some fine match bullets that you over crimped them. You have to pull them later to find out that the crimp is excessive.

    No competitive shooter uses a lee FCD on match ammo.

    So I wonder, what advantage do they provide?
  11. jpwilly

    jpwilly Well-Known Member

    I only use the FCD on 45ACP SWC to keep them from jamming back in my 1911. Otherwise you don't need it the Bullet seating die is generally enough for rifle rounds even for my AR's.

Share This Page