Inline FabricationLoad DataWidenersMidSouth Shooters Supply
Reloading EverythingTitan ReloadingLee PrecisionRepackbox
RotoMetals2
Results 1 to 8 of 8

Thread: Popular Supersonic 300 Blacklout Mold

  1. #1
    Boolit Mold


    Join Date
    Nov 2011
    Location
    Idaho
    Posts
    23

    Popular Supersonic 300 Blacklout Mold

    I have looked through multiple forums in an effort to see if there are any popular supersonic 300 blackout molds in the 125 to 165 grain range for an AR-15. I see mention of the Mihec 311410 and Lee 312-155. Are there others that I missed?

    The Mihec 311410 does not appear to be available and I am concerned that the crimp location may not be proper for the Blackout. I am concerned with the quality of the Lee and would prefer something that did not have to be sized down so far.

    I am hoping to push the bullet to 1800-1900+. Will I need a gascheck to maintain accuracy and\or minimize leading. I will probably coat with HTC, but could end up lubing.

    I would appreciate any comments on the above. Recommendations would be most appreciated.
    Last edited by wkelley70; 03-15-2018 at 05:26 PM.

  2. #2
    Boolit Buddy
    Join Date
    Mar 2008
    Posts
    317
    I have the Lee 312-155 in a 6 cavity. I had a little problem with it initially, which was admittedly my fault. If I had been doing things right, I would have been droping nothing but perfect boolets the whole time.

    I'm still in the process of working up a good load, so I can't speak to the overall accuracy of the boolet, since there are to many variables that could be affecting my accuracy right now. Things are looking positive, however.

    I've tried HTC and PC, and so far don't notice a difference between the two. I've tested with gas checks, but I do have around 20 rounds ready to go without gas checks just to see what happens.

    Overall I'd say you really can't go wrong with the Lee. If you're really worried, get the 2 cavity for $20. If you end up not liking it, you're not really out much money, and you can always bump up to the 6 cavity if you end up liking it
    Last edited by asmith80; 03-15-2018 at 07:28 PM.

  3. #3
    Boolit Buddy
    Join Date
    Feb 2018
    Location
    AL
    Posts
    330
    I also have the lee 6 cavity and it shoot great. GT bullets has the MP 311410 cast for sale. I just bought 500 to try in blk out, 308, 30-30 single shot, and 30-06. The Lee 312-155 I load with lil gun powder. I am pushing it a little over 1900 fps. Boolits are water dropped from the mold and yes you need gas checks. The 311410 is a little short to feed from my ruger in 300 blk when seated to crimping groove. I seated it about 3/4 of the first driving band and crimped it and it feeds in the ruger and my AR. Iwont have a chance to shoot till sat and will try that boolit/load for the first time. The boolit just starts to engrave the rifling in both rifles when seated out like that. I size the Lee to 311 and it shoots fine..Watch your case neck thickness or you will stick one in the chamber and it wont come out without help. I learned to use a screwdriver thru mag well to gently pry the bolt/cartridge out of chamber in AR.
    Last edited by shortlegs; 03-15-2018 at 07:28 PM.

  4. #4
    Banned
    Join Date
    Jul 2016
    Posts
    2,911
    The Lee 312-155 I load with H110

  5. #5
    Boolit Master

    Moonie's Avatar
    Join Date
    Apr 2010
    Location
    Thomasville North Carolina
    Posts
    4,695
    I have that mold in 2 cavity and when they came out with the 6 cavity I purchased it as well. For supers in 300 BO it is very hard to beat.

  6. #6
    Boolit Master RU shooter's Avatar
    Join Date
    Nov 2006
    Location
    SW Pa.
    Posts
    2,928
    I always had my best accuracy with the rcbs 165 sil bullet , the lee 185 and the 155 shot well also in my rifle.
    If you find yourself in a fair fight, your tactics suck!

  7. #7
    Boolit Master

    Hamish's Avatar
    Join Date
    Jan 2011
    Location
    Edge of The Crab Orchard National Wildlife Refuge
    Posts
    3,569
    The Lee 155 is the most reported to be easy to use and get good results with on this forum, bar none. Use it myself.
    More "This is what happened when I,,,,," and less "What would happen if I,,,,"

    Last of the original Group Buy Honcho's.

    "Dueling should have never been made illegal in this country. It settled lots of issues between folks."- Char-Gar

  8. #8
    Boolit Master


    Join Date
    Jul 2010
    Location
    Ft. Lauderdale, FL
    Posts
    1,253
    I know somebody that says that an NOE Spitzer boolit is the only way to fly for 300blk supers. Problem is I can't recall the number. It's a little lighter than the Lee. Maybe the Other Duke in Florida will chime in at some point.
    ΜΟΛΩΝ ΛΑΒΕ

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