Less powder more velocity?

Lance B

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Is it possible that a load with less powder 42.8 H4350 vs. 43. would give a greater velocity. And if so why would this be?
 

Fuzzball

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Re: Less powder more velocity?

Ahhhh...what cartridge might you be loading?
 

Mudcat-NC

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Re: Less powder more velocity?

Yes. Effieciency. If you get too much in there and it doesnt burn, you slow down. Ever notice when you get closer to the top you start losing gains?

John
 

Fuzzball

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Re: Less powder more velocity?

Ahhhh...what cartridge & bullet might you be loading?

It's normal to see decreasing speed per grains of powder increases. But it's not normal to see a loss of speed per added grains of powder.
 

Lance B

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Re: Less powder more velocity?

Sorry, it was for a .243, Lapua brass, CCI primers, 115 DTAC's
 

Mudcat-NC

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Re: Less powder more velocity?

Well, and youre probably near the top end I think (I dont load much 243) and youre only at .2 gr difference and that alone, with just one chrono reading, could give you less speed.

John
 

19Scout77

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Re: Less powder more velocity?

Lance- Did you use the same chronograph both times you shot?

Also-- CONGRATS!! Nice job on Saturday!
 

7mmRM

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Re: Less powder more velocity?

Ive seen this happen a few times. Last time was just a few weeks ago with a 7mm08 & RL17.
 

Lance B

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Re: Less powder more velocity?

19Scout77, thanks and yes same chronograph both times.
 

FNuser

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Re: Less powder more velocity?

Was the seating depth the same? if you seated deeper and the volume was decreased you can gain velocity also if you seat longer but you're in the lands( some people say jam) that can increase pressure and velocity as well hope this helps.
 

rijndael

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    Re: Less powder more velocity?

    What do you use to weigh your powder?

    How many rounds did you fire to draw this conclusion?

    How long does a round sit in the chamber before you fire it? Are you consistent with this delay in firing?
     

    paraman1

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    Re: Less powder more velocity?

    I had the same thing happen with my .308 and 155 grain Noslers . 46.5 grains of Varget produced more velocity than 47.0 but the 47.0 load was more accurate . I have a second batch ready to go test again and see how it works out on the second go round .