throat erosion ?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Caleb85, Aug 12, 2014.

  1. Caleb85

    Caleb85 Well-Known Member

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    I have put about 80 rounds of 168gr VLD through my 7mm this summer and in that time I have lost 6 thousands out of my throat! !!.. is this common with the burgers and or 66 gr. Of H1000?. Has anyone else seen this problem?
     
  2. Mikecr

    Mikecr Well-Known Member

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    How many total rounds down the barrel?
    What is your shot rate? Much group shooting?
     

  3. MagnumManiac

    MagnumManiac Well-Known Member

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    This is normal, expect to see this continue, it may or may not proceed at the same rate, but it WILL proceed.

    Cheers.
    gun)
     
  4. Caleb85

    Caleb85 Well-Known Member

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    Now this rifle has sen around 800 to 1000 rounds..but I didn't notice the erosion. I used a OAL tool at the start of the summer to load my vld's and I just used it again and the throat is 6 thousands longer then it was 80 rounds ago. It's been mostly all group shooting and my shooting rate is what I would say normal ..i do remember one time I got the barrel hot but I don't normally .
     
  5. AZShooter

    AZShooter Well-Known Member

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    A friend shoots 1000 BR with a 300 win mag improved. He would make the comment that he would chase the throat with every match. They shoot a few rounds as sighters then shoot 10 for record with those big guns. So perhaps as many as 15 rounds were sent downrange in just a few minutes.

    At least your rifle is showing this wear at a slower rate. Of course if you don't shoot it much it can last for years.

    I wouldn't be too concerned yet. I have a bore scope and have inspected my 257 weatherby and a 6mm-284 that both have around 1000 rounds through them and are horribly eroded with a great deal of heat cracking WAY up the barrel. They are much harder to clean BUT they still shoot quite well. I have new barrels waiting to replace them and keep wondering when that will happen.
     
  6. Caleb85

    Caleb85 Well-Known Member

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    Ya I think I might take barrel off and keep it so with my son is old enough to shoot, he can shoot it out and have a barrel that says "sendero" on it ...cuz what 14 year old don't want a factory sendero! !?:D. But anyway thanks for the replys but I'm not chasing or setting the barrle back, just one more project! !
     
  7. MagnumManiac

    MagnumManiac Well-Known Member

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    I shoot 1000yrd comp here in Australia with 2 distinct cartridges, the 300WM and 338 Edge, in my early days I would chase the lands, to no avail. I would have to start working loads again every time I did this. David Tubb has done several articles on this, as well as barrel contours away from the norm that shoot lights out even though they're lightweight.
    Now, I don't even take notice of the amount of erosion, if vertical stringing starts plagueing my groups, I check velocity, if it's dropped, I work back up to the previous known velocity and test for groups. This normally sees me where I was without any tweaking needed.
    Now, not to be condescending at all, if your rifle isn't a highly tuned custom gun, then either chasing the lands or my above method may make little difference to your outcome, accuracy will slowly drop off and will never come back. I have had very good accuracy out of a 300 barrel well past 1500 rounds, it all boils down to care and regular cleaning, but not excessive cleaning.

    Cheers.
    gun)
     
  8. Mikecr

    Mikecr Well-Known Member

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    See your original question was worded poorly in that you implied 6thou erosion in just 80rnds fired through the barrel. Not ~1080 rounds.
    It is normal for erosion to hold-off a while and then accelerate. The acceleration will continue to climb until eventual accuracy loss.
     
  9. AZShooter

    AZShooter Well-Known Member

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    MagnumManiac,

    Thanks for your explanation. Also good to hear that you bump powder charges to get back to the original velocity'grouping. I will have to remember that, in fact your comments will be put into my documents for future reference.

    I was never one to chase lands and never noticed a deterioration in accuracy but then again my rifles are hunting/varmint rifles. I mentioned my friend chasing the lands to explain to the OP that it isn't an uncommon thing to have throat erosion.