Lee PrecisionRepackboxRotoMetals2Wideners
Inline FabricationTitan ReloadingBonettMidSouth Shooters Supply

Results 1 to 17 of 17

Thread: 300 AAC loading questions

  1. #1
    Boolit Master Blood Trail's Avatar
    Join Date
    Apr 2014
    Location
    Lone Star State
    Posts
    1,428

    300 AAC loading questions

    I have a 311410 MP mold that throws a 125 gr HP or 130 gr fn. these bullets are pcíd and gcíd. Iím following data from the Lee manual for a 125 gr jacketed bullet using 20 grs of CFEBLK (min load).

    Those who load this bullet, what OAL do you use?


    Edit: Loading, not losing

    Sent from my iPhone using Tapatalk
    Last edited by Blood Trail; 08-02-2022 at 07:27 PM.

  2. #2
    Boolit Master
    Join Date
    Jan 2011
    Location
    NE Kansas
    Posts
    1,984
    You have introduced too many variables to get an answer from a book. Try this instead.

    Cleaning rod/dowel method of finding cartridge OAL

    This is what I use for my guns to determine the max OAL and this eliminates any question of the crimp, incorrect case prep, or other operator induced error.

    This method works well on rifles and single shot pistols as well as Semi-autos. You can use a flat tipped cleaning rod, or flat tipped dowel rod. You will also need a sharp pointed pencil, a short dowel and a bullet sized but clean, of the type you are going to load.

    For Rifles
    Make sure the chamber is empty. Close the bolt, and be sure the firing pin is retracted into the bolt. Insert the dowel or cleaning rod and hold it against the face of the bolt. Mark the rod at the face of the muzzle. Remove rod, open bolt and remove it from the action. Insert the bullet into the breech and hold it snug into the rifling. While in that position insert the dowel or rod again, and with it firm against the nose of the bullet, mark the rod at the face of the muzzle.

    The distance between the center of those two marks is the max cartridge OAL for that rifle, with that bullet sized to that diameter.

    For Semi-autos
    Remove the barrel from the slide and make sure it is clean and free of leading or other debris in the barrel and chamber. The dowel or cleaning rod needs to be longer than the barrel. Hold the barrel, muzzle up, and place the barrel hood on a flat surface like a table top. Insert the dowel or rod from the muzzle and mark the rod exactly flush with the muzzle. Remove the rod and insert the bullet you intend to use into the chamber and lightly press and hold it in place with the short dowel. Place the assy muzzle up on the flat surface. Insert the rod/dowel into the muzzle so it rests on the nose of the bullet and again mark the rod exactly flush with the muzzle. Remove and set the barrel aside. The distance on the center of the two lines is the cartridge OAL. Seat a dummy round to this length, or slightly shorter and begin to apply the taper crimp until the dummy passes the plunk test. This is the optimim cartridge OAL length for this bullet in this gun.

    You may need to adjust the seater to shorten the OAL if this does not feed from the magazine, but generally this will be a great fit. Remember, if you seat and crimp in one step, you might force a slight ridge ahead of the case mouth and that will screw up your seating.
    Dusty

  3. #3
    Boolit Grand Master popper's Avatar
    Join Date
    Jun 2011
    Posts
    10,032
    Make a dummy rnd seated short, if it chambers, seat less deep. Try again till it is hard to chamber. Some make it long and then push shorter - which ever. Then back off seating depth about 20 thous. as PC thickness changes. Hand cycle in your gun. If it chambers and ejects OK, good.
    Measure bullet base to mouth. COMPARE with the book bullet COAL for the BOOK bullet, same or heavier than yours. Look at book max load and pressure if given. If you seat deeper than book, decrease powder load to keep pressure down. You are trying to calc the load fill. QL or GRT will do that for you. Book COAL has nothing to do with their test barrel or bullet but load FILL.
    You can start at min load and use a chrony to move up. Powders like H110 don't give much spread, max-min. CFE BLK likes to run 90-95 % filland can be slightly compressed..
    Whatever!

  4. #4
    Boolit Master
    Join Date
    Mar 2012
    Location
    NE Oklahoma
    Posts
    586
    If you are loading for an AR, good luck and it doesnít matter. Iíve seated it all the way in and out, with several powders, and several charges, and canít get it to feed and function. The bullet is too short and you canít seat it out long enough because of the large lube groove.

    If you get it to work i would like to know.

    If itís not for an AR, I would seat to the crimp groove.


    Sent from my iPhone using Tapatalk

  5. #5
    Boolit Grand Master Texas by God's Avatar
    Join Date
    Mar 2016
    Location
    Texas
    Posts
    12,574
    In an AR15, seat to magazine length. If they won't chamber, try seating a little deeper. I hate it when ejecting an unfired round pulls the bullet out and spills powder into the action.

    Sent from my SM-A716U using Tapatalk

  6. #6
    Boolit Master Blood Trail's Avatar
    Join Date
    Apr 2014
    Location
    Lone Star State
    Posts
    1,428
    Thanks all. I ended up at 1.89Ē OAL. They cycle fine. Iíll test for accuracy today.


    Sent from my iPhone using Tapatalk

  7. #7
    Boolit Master Blood Trail's Avatar
    Join Date
    Apr 2014
    Location
    Lone Star State
    Posts
    1,428
    Quote Originally Posted by sukivel View Post
    If you are loading for an AR, good luck and it doesnít matter. Iíve seated it all the way in and out, with several powders, and several charges, and canít get it to feed and function. The bullet is too short and you canít seat it out long enough because of the large lube groove.

    If you get it to work i would like to know.

    If itís not for an AR, I would seat to the crimp groove.


    Sent from my iPhone using Tapatalk
    At 1.89Ē they work. I popped off a few with no issues.




    Sent from my iPhone using Tapatalk

  8. #8
    Boolit Grand Master Texas by God's Avatar
    Join Date
    Mar 2016
    Location
    Texas
    Posts
    12,574
    Those look great. I’m looking forward to the range report.
    It’s a fun little cartridge.

  9. #9
    Boolit Master Blood Trail's Avatar
    Join Date
    Apr 2014
    Location
    Lone Star State
    Posts
    1,428
    Range report:

    50 yards with a red dot. No magnification. Not bad for a plinking round. No jams. Two mag dumps without a hiccup. AR-15 pistol 7.5Ē barrel




    Sent from my iPhone using Tapatalk

  10. #10
    Boolit Master
    Join Date
    Mar 2012
    Location
    NE Oklahoma
    Posts
    586
    Quote Originally Posted by Blood Trail View Post
    At 1.89Ē they work. I popped off a few with no issues.




    Sent from my iPhone using Tapatalk
    Thatís about where my OAL was. What powder are you using?

    Was that the HP or solid?


    Sent from my iPhone using Tapatalk

  11. #11
    Boolit Master Blood Trail's Avatar
    Join Date
    Apr 2014
    Location
    Lone Star State
    Posts
    1,428
    Quote Originally Posted by sukivel View Post
    Thatís about where my OAL was. What powder are you using?

    Was that the HP or solid?


    Sent from my iPhone using Tapatalk
    20.4 grs of CFE BLK. I shot a combo of both. They pretty much hit the same.


    Sent from my iPhone using Tapatalk

  12. #12
    Boolit Buddy Krh1326's Avatar
    Join Date
    May 2022
    Location
    Behind Enemy Lines, NY
    Posts
    129
    It kills me that, we have cast boolits and their molds that have exposed lube or crimp grooves ? I know itís just aesthetic, but it really looks stupid. Why canít these mold manufacturers make a mold that is ďsupposedlyĒ for 300 BLK actually BE for 300 BlkÖ ? Grooves, including crimp where they are supposed to be , in a practical spot? Why are they making these boolits to difficult COLs for feeding, battery..etc?

    My rant for the day. I feel better now. Carry onÖ.

  13. #13
    Boolit Master Blood Trail's Avatar
    Join Date
    Apr 2014
    Location
    Lone Star State
    Posts
    1,428

    300 AAC loading questions

    Quote Originally Posted by Krh1326 View Post
    It kills me that, we have cast boolits and their molds that have exposed lube or crimp grooves ? I know itís just aesthetic, but it really looks stupid. Why canít these mold manufacturers make a mold that is ďsupposedlyĒ for 300 BLK actually BE for 300 BlkÖ ? Grooves, including crimp where they are supposed to be , in a practical spot? Why are they making these boolits to difficult COLs for feeding, battery..etc?

    My rant for the day. I feel better now. Carry onÖ.
    I agree. I tried crimping one to the top lube groove. The OAL was so short Iíd thought Iíd run into pressure issues due to powder compression. However, it suits my needs, so Iíll have to live with it.


    Sent from my iPhone using Tapatalk

  14. #14
    Boolit Master 44Blam's Avatar
    Join Date
    Sep 2017
    Location
    Nashville, Indiana
    Posts
    1,530
    I make a sample boolit and seat it as long as will fit in a magazine or max col for the cartridge and I crimp it how it will be crimped. Then I attempt to chamber it. If it goes - your done. If not pull the boolit, resize the case, bell, seat crimp again just a little shorter. You can kind of gauge on how much shorter by how close you are to chambering.
    Once you have that, cycle that dummy a bit - maybe it needs to be shorter still?
    WWG1WGA

  15. #15
    Boolit Master
    Join Date
    Mar 2012
    Location
    NE Oklahoma
    Posts
    586
    All this talk is making me want to revisit this again.

    I seated my last bunch at 1.85, so Iíll go to 1.9 and see what happens. I was thinking that 1.85 was as long as I could go for some reason. Anyhow my notes arenít that detailed.


    Sent from my iPhone using Tapatalk

  16. #16
    Boolit Master 44Blam's Avatar
    Join Date
    Sep 2017
    Location
    Nashville, Indiana
    Posts
    1,530
    OH! I remember what gave me 100% feed reliability with 300 BO. Hi-Tek.
    The mold I am using is the NOE HTC310-225-RN-CE4 and I did have some occasional issues feeding when I was PCing the boolits. I started Hi-Tek coating my 300 BO boolits and I have not had any issues since.
    WWG1WGA

  17. #17
    Boolit Grand Master popper's Avatar
    Join Date
    Jun 2011
    Posts
    10,032
    Just get a mould without grooves. They aren't needed if you PC or hitek. I've even used them with 2 coats BLL and no problem to about 1600 fps.
    Whatever!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check