300 RUM Leaving Black Soot on Brass

Discussion in 'Reloading' started by baydog, Feb 18, 2014.

  1. baydog

    baydog Well-Known Member

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    Hello. I was hoping someone could help me figure out why my brass is getting soot on it from the neck right on down to the bottom of the brass. The only thing I can figure is that the load isn't hot enough causing the case not to expand enough to seal and that is allowing some burnt powder to sneak by and stick to the brass and this probably is my fault for not loading enough powder. It's a new Remington Sendero 300 RUM. I thought i would be nice to the gun for the first couple of break in shots and load a lighter bullet and a lighter load of powder. I thought i was doing the right thing but probably not. I bought some 180grain ballstic tips and some 200 grain accubonds bullets and Retumbo powder. I had some 150 grain Serria bullets and I loaded them with 95 grains of Retumbo powder. The #7 Nosler Reloading Data book says the lightest load for this weight of a bullet is 98 grain but to be nice to my new gun I thought the first couple of shots i would load a little lighter, then after a couple of shots shoot a coulpe more 150 grain bullets but step up to 98 grains of powder then go ahead and step up to the the 180 grain bullets with 93 grains of Retumbo then load no more or less then the Nosler data says too. I have never swayed off the Nosler Data until now. I know I'm probably gonna get yelled at for swaying off the data book but thought i was doing the right thing just for break in purpose. I was going to load a few more but go ahead and step the powder up to the minimum powder charge of 98 grains of Retumbo with a couple more of the 150 grain bullets then go ahead and load some 180 grain bullets at noslers minimum powder charge for Retumbo and start looking for a recipe that the gun likes. I've probably caused my own problem but wanted to know if that could be the reason for the soot on the brass and thats because the case isn't expanding enough to seal the powder burn. Thanks for your time and help.

    baydog
     
  2. baydog

    baydog Well-Known Member

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    help!
     

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  3. Doublezranch

    Doublezranch Well-Known Member

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    I couldn't have said it better myself....:D

    "I've probably caused my own problem but wanted to know if that could be the reason for the soot on the brass and thats because the case isn't expanding enough to seal the powder burn."

    That's exactly what happened. Too light of a load that didn't expand the case enough to seal the chamber. Toss a couple more grains in the case and let her rip. That should take care of your problems.
     
  4. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    light for caliber bullets, slow for caliber powder, below minimum charge for the data book; Heck, I'm surprised you aren't asking how big of a hammer you need to knock the bullet out because it squibbed. Try a slightly faster powder with a bit more bullet weight if you want moderate performance.
     
  5. mtdonahue

    mtdonahue Well-Known Member

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    You hit it right on, you caused yourself you be a victim. Probably lucky not to stick one in the tube. Use a faster powder for the 150's, Retumbo is great for the heavier bullets. No reason to be below minimum load. Throw some more powder in and go have fun, mark it up as a lesson learned.
     
  6. scpaul

    scpaul Well-Known Member

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    I agree that the problem is low pressure and light bullets, but does the brass seem to have a pattern in the soot ?
     
  7. baydog

    baydog Well-Known Member

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    Thanks everyone for your help. I will load again and never sway off the reloading data again thats for sure! I'll let you know how it works out and Thanks again..

    baydog
     
  8. baydog

    baydog Well-Known Member

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    Don't really see no pattern scpaul..Thanks

    baydog
     
  9. MontanaRifleman

    MontanaRifleman Well-Known Member

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    What I did to break-in my 300 RUM in was to use the heaviest bullets and slowest powder I could, which was 230 Hybrids and RL33. There is no data for that combo and I was seeing most guys were maxing at about 100 gr or so so I downloaded it 10% to 90 gr. MV was right about 2700. That is a good break-in load for the 300 RUM.

    If you want to be nice to your rifle, shoot the heaviest bullets you can with a reduced charge of slow powder. Lighter bullets will produce a lot more velocity than heavy bullets with the same pressure. Heavy, slow bullets is good to your rifle.
     
  10. baydog

    baydog Well-Known Member

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    Wanted to let everyone know that you were all right and thank you for your help. Bumped the powder up from 95 grain to 98 grain and the case looks as it should. Clean from top to bottom. may be a little at the very tip top of the neck but thats as about as normal as it gets to me. Thanks again

    baydog :D
     

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