# Got my DPMS 300 BLK upper today



## fr3db3ar (Aug 6, 2011)

I'm a little stoked. Almost ready to load up some subsonics and give her a whirl.

Will the sizing/loading dies also form the brass that I cut down?


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## prairiewolf (Feb 19, 2012)

I dont know about the 300 blackout, but when I had a 30 herret. I had to cut the brass down on a 30-30 case and then load up light loads to fire form the cases.


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## fr3db3ar (Aug 6, 2011)

300 blk is. 223 based

Sent from my somewhere in the space time continuum.


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## Rediculous (Oct 16, 2013)

Just make sure it's full sizing die and not just the neck die. Have fun


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## prairiewolf (Feb 19, 2012)

Fred, try this link

http://www.thetruthaboutguns.com/2013/07/jim-barrett/300-blackout-rolling-your-own-is-easy-with-carolina-brass/


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## youngdon (Mar 10, 2010)

Congrats Fred ! You're gonna like that round.

Yes it will resize it correctly. There should be no need to fireform this round.


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## fr3db3ar (Aug 6, 2011)

Yeah, I'm not going to buy brass. I've got a lot of .223 brass that I don't use for my guns. I'm only reloading LLC brass for the .223 and I have a couple different jars full of fed, win, pmc etc. I'll cut that down, try some annealing with the torch and drill (this will be a good time to practice that) load them up. I still have to wait for the trimming gauge to get here. I forgot to order it with the bullets and dies :/


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## youngdon (Mar 10, 2010)

Which trimmer gauge did you buy ?


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## fr3db3ar (Aug 6, 2011)

Lee, all I really needed was the stem

Sent from my somewhere in the space time continuum.


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## Rediculous (Oct 16, 2013)

yeah in a semi-auto fire forming is impossible anyway :nut: i didnt see it was a dpms


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## knapper (Feb 5, 2010)

I bought my 300 blk brass and there is no way to mix up the two rounds in the wrong chamber due to the shape of each one. For the most power out of it I use 150 gr. bullets, there is almost the same velocity as the 125 and when using AA 1680 powder it works real well. Tried the 208 gr. and they would not function in my carbine length gas tube. They are lots of fun to shoot and a pain to search for on the ground because they look a lot like 7.62X39 on the ground.


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## fr3db3ar (Aug 6, 2011)

I think the 150s put us in the class of the 30-30 IIRC


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## youngdon (Mar 10, 2010)

fr3db3ar said:


> Lee, all I really needed was the stem
> 
> Sent from my somewhere in the space time continuum.


Those work great, I have about a dozen or so in different calibers. I've chucked them in a cordless drill for quantities.


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## Nickb (Nov 3, 2013)

Looking forward to seeing how you like it. I'm thinking of building a pistol in .300blk.


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## fulch (Apr 2, 2013)

Nickb said:


> Looking forward to seeing how you like it. I'm thinking of building a pistol in .300blk.


+1. What barrel length are you considering, I seem to hear 9" come up frequently in that platform but have yet to do my own extensive research.


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## Nickb (Nov 3, 2013)

Between 9 and 11.5. It really depends on what is available when I'm ready for a barrel.


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