can a barrel get faster?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by cbryant, Nov 17, 2013.

  1. cbryant

    cbryant Member

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    Oct 2, 2011
    rifle= trued rem action
    26" krieger barrel
    1-8.5
    brass hornady
    52.5 gr rl22
    140 gr berger vld

    now when i first broke the barrel in and started shooting for my drop charts it shot very well at about 3020 fps through the chronograph
    after about 75-100 shots it seemed like my dope charts were high and i was taking clicks off, now my dope is very dead on out to 1200 yards and the speeds i have in my shooter program is 3150 is this possible?gun)
     
  2. osoh

    osoh Well-Known Member

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    Sep 3, 2013
    From my experience it takes about 100 rounds down a new barrel to burnish in or settle to where the speeds tend to climb and then stabilize at a given speed.

    osoh
     

  3. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    Yep, I've seen it with a couple of rifles, notably my 7rum. As she wore she gained nearly 100 fps with 140 sierra pills pushed by rl25. They can also fall off a bit in vel. too. Osoh's reasoning would be for faster, but if you already have a pretty good bore and you wear the throat enough the pressure can fall off enough to actually slow the load a bit.
     
  4. aramarine6

    aramarine6 Well-Known Member

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    Apr 22, 2010
    Were you shooting in or near the same temperature? Ammunition temperature can make a difference in velocity as well. Granted a 10 degree change wont amount to 100 fps difference, however a 40 or 50 degree difference in ammo temp can cause a significant velocity change. In my 338 RUM I'll have a maximum spread of 200+/- fps between 100 degrees and 0 degrees. With that being said, If you did shoot in similar temperature conditions then it is most likely your barrel has reached its copper equilibrium and has built up alittle more pressure and consistency.
     
  5. CB11WYO

    CB11WYO Well-Known Member

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    Yup, friend's 30-378 recently had the same issue. Out of the blue his reticle had him hitting high every time he pulled the trigger. His gain was around 100-150 fps if I remember right.


    PS- cbryant, if your first name is Clint... we have the same name, first and last :D
     
  6. Alonzo

    Alonzo New Member

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    Oct 23, 2013
    It is not unusual to have a barrel speed up in the first 80 to 150 rounds by an average of 40 to 50 fps but I have had barrels increase speed by as much as 140 fps it's not typical but it does happen.
     
  7. cbryant

    cbryant Member

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    Thanks for all the replies iam glad iam not crazy:) dorry clint we dont share thr same name