Results 1 to 7 of 7
  1. #1
    User
    Join Date
    Mar 2015
    Age
    60
    Posts
    1

    Default 300 BLK AR15 DDM4V7 Upper

    Need some help reloading subsonic ammo 220gr point CCI400 Small rifle primer for 300 Blackout 16" barrel Semi Daniel Defense DDM4V7.

    I have bought powders MP200, S221, S265, S321, S335 and S341 to test.

    Powders MP200, S221, S265 can speed up the 220gr point to easily 1030 fps but does not create sufficient gas to cycle (reload)the action.

    Powders S321, S335, S341 cycle the action but not enough speed, powder reaches case capacity.

    If I mix powders MP200 and S335, 3.3gr and 8gr I get the action to cycle occasionally. (Reaches case capacity)
    If I mix powders MP221 and S431, 4gr and 7.5gr I get the action to cycle occasionally. (Reaches case capacity)

    Using factory ammunition Remington 300 AAC BLACOUT 220gr OTM R300AAC8 it cycles every time, I have stripped a round and found 10.5 gr propellant inside. Using this loud in one of my casings with CCI400 primer and 220gr Nosler HPBT point it cycles the action no problem.

    I have tested different buffer spring and H3 buffer weight.

    Somchem powders does not produce sufficient gas to cycle action.

    I have posted a email to Somchem for guidance.

    Any advice?

  2. #2
    User
    Join Date
    Feb 2012
    Location
    Pretoria
    Posts
    3,327

    Default Re: 300 BLK AR15 DDM4V7 Upper


  3. #3
    User
    Join Date
    Aug 2016
    Location
    (021)
    Posts
    1,501

    Default Re: 300 BLK AR15 DDM4V7 Upper

    Can any of the mnore experienced reloaders comment on the OP's mention of mixing propellant powders to achieve a desired result with his rifle.

    I am still relatively new to reloading, and have never heard of people doing this, but my common sense tells me that this one of those "don't try this at home" ideas, in other words, you could literally be playing with fire.

  4. #4
    Banned
    Join Date
    Aug 2012
    Location
    Stella
    Age
    46
    Posts
    10,870

    Default Re: 300 BLK AR15 DDM4V7 Upper

    During the 80's it was common amongst some of the pistol shooters in SA to mix different gun powders to obtain certain characteristics. An older shooter explained it in a thread maybe three years ago.

    In rifles it is known as duplex loads. X grains of powder A on top of Y grains of powder B gives a hotter flame later in the burning process at a lower pressure. If memory serves correct the initial charge is slower burning powder which ignites the charge of faster burning powder.

    In handguns it can apparently be done but in rifles it is generally considered a part of dark science aka alchemy and asking for trouble. I know of one person in Namibia who has ample experience in this.

  5. #5
    User
    Join Date
    Dec 2009
    Location
    JHB
    Age
    41
    Posts
    2,985

    Default

    Quote Originally Posted by StanCT View Post
    Can any of the mnore experienced reloaders comment on the OP's mention of mixing propellant powders to achieve a desired result with his rifle.

    I am still relatively new to reloading, and have never heard of people doing this, but my common sense tells me that this one of those "don't try this at home" ideas, in other words, you could literally be playing with fire.
    Generally a bad idea and to be avoided. If you don't know what you're doing you could detonate a gun.

    As to the original question, why not try the new powders coming in from overseas?

  6. #6
    User
    Join Date
    Jun 2011
    Location
    Cape Town
    Posts
    1,363

    Default Re: 300 BLK AR15 DDM4V7 Upper

    I'm just going to throw this out there, but I'm unfortunately NOT speaking from experience - would an adjustable gas block not be required for this kind of situation? I know, you said that factory Remington loads do cycle properly, so I can understand the desire to try and match them, but I personally wouldn't be mixing powders, due to my own inexperience with such, and having read that it's a bad idea unless you REALLY know what you're doing (I can't comment on the OP's experience, so no judgement).

  7. #7
    User
    Join Date
    May 2014
    Location
    JHB
    Posts
    2,657

    Default Re: 300 BLK AR15 DDM4V7 Upper

    Quote Originally Posted by ARM505 View Post
    I'm just going to throw this out there, but I'm unfortunately NOT speaking from experience - would an adjustable gas block not be required for this kind of situation? I know, you said that factory Remington loads do cycle properly, so I can understand the desire to try and match them, but I personally wouldn't be mixing powders, due to my own inexperience with such, and having read that it's a bad idea unless you REALLY know what you're doing (I can't comment on the OP's experience, so no judgement).
    Well the 300blk is designed be able to be shot suppressed with subs and supersonic without making any changes, and being a DD from my reading it should be pretty spot on although the 16" barrel isn't ideal for shooting subs it's not a deal breaker.

    The main drawback is our locally produced propellants, which of the lot the best bet is the S265, but as you have found it's touch and go at best with subs... Supers though it's great.

    Maybe try some of the imported propellants? I know there has been some talk of one of the Vihtavuori that looks like it would work, but the exact type slips my mind now. I also know there are Hodgdon Propellants which would work, and there was talk that DSG would be bringing in some Lil Gun, and CFEBLK in the next batch... whenever that is.

Similar Threads

  1. [FOR SALE] Magpul AR15 Accessories and AR15 Rifle Tool
    By Chris8 in forum Accessories for Sale (Parts, Magazines, Stocks, Scopes, Reloading etc.)
    Replies: 13
    Last Post: 07-02-2015, 17:04
  2. [NEW IN] AR15 Upper and Lower Parts - Available from HAILSTORM
    By Hailstorm in forum HAILSTORM
    Replies: 6
    Last Post: 06-02-2015, 20:54
  3. [FOUND] .22 upper for AR 15
    By NovaG7 in forum Found
    Replies: 0
    Last Post: 03-10-2014, 22:41
  4. [FOR SALE] DD 300 BLK Upper
    By FrankH in forum Firearms / Guns for Sale
    Replies: 5
    Last Post: 28-09-2014, 09:54
  5. AR15 upper/lower wobble
    By Lian in forum General Firearm Discussion
    Replies: 10
    Last Post: 09-11-2013, 17:06

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •