Amazing accuracy method

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Engineering101, Feb 24, 2014.

  1. Engineering101

    Engineering101 Well-Known Member

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    My nephew said a gunsmith friend of his put him on to tuning the rifle to the load with chamber bedding that is cut back until it shoots good. Anyway, my nephew developed a load for his 338 Edge that had good velocity without pressure signs. He didn’t worry about accuracy other than to note what it was. The load shot 1.5 inches at 100 yards. Then he cut back the bedding ¼ inch and went back to the range. With the exact same load he is now getting ragged holes at 100 yards. Per the gunsmith you are then supposed to do some minor tweaking of the load to really tighten it up. The gunsmith has the best of his rifles shooting 0.3” ten shot groups at 200 yards with this tuning method.

    I was always told to float the barrel which means you don’t bed the chamber part of the barrel. But I’ve seen the targets and they are pretty compelling. I may have to give this a try but before I do I thought I’d ask if this is general knowledge and I just didn’t get the memo. Any of you guys that do some tweaking already doing this? Any thoughts?
     
  2. Jud96

    Jud96 Well-Known Member

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    We've always bedded about 2inches of the barrel channel then floated the rest of the barrel. This has given us excellent accuracy on many, many, rifles.
     

  3. Dosh

    Dosh Well-Known Member

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    101, sounds worth an attempt and easy to perform. Only takes a small amount of bedding material to replace it if it doesn't work. The barrel contour would also be a factor.
     
  4. royinidaho

    royinidaho Writers Guild

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    Hmmmm, nothing new about that, at least for me.

    Though I bed first then shoot. I bed the chamber section plus "a little". The working up the load part is fairly quick.

    I noticed that a couple of high priced customs I have were bedded similarly by a noted smith on here.

    Either way to the OP. Great find!!!!
     
  5. bigngreen

    bigngreen Well-Known Member

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    There are several methods that more or less tune the barrel harmonics, I've used a stock that had an adjustable tuner that turning the screw moved a pressure point on the barrel and you could see it dial in. It may produce groups in the short range that are note worthy but you still will need to dial the load in to get ES at a level that you'll have precision at long range.
     
  6. Topshot

    Topshot Well-Known Member

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    There is one problem with this type of bedding. It can cause point of impact changes when you use a different shooting position or rest.
    The for end of most stocks have a fair bit of flex in them. Grab your barrel and the for end of your stock and press them together with your hand. See how much flex there is by the change in the gap between stock and barrel.
    Now on a fully free floated barrel this will impart no force upon the barrel. However with the stock bedded for an inch or two under the chamber, the stock now acts as a large lever and can impart quite a substantial amount of force upon the barrel knox form.

    If this pressure is constant as in when shooting off sand bags off a bench, accuracy can be very good. You will go away thinking you have a great rifle that will slay all manner of game .
    However when we go hunting, our field shooting position and our rests can vary quite a bit. This can and will result in variations to the amount of force being applied to the for end of the rifle. This force is magnified by the compound leverage of the long for end and the short bedding under the chamber.

    So in my opinion it is better to have a rifle that is fully free floated. You may end up with slightly less grouping ability off the bench but you will have a far more reliable field rifle.
     
  7. Jud96

    Jud96 Well-Known Member

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    Never had that problem with any of my rifles. Mine shoot just fine whether killing deer at 50yds or shooting rocks at 700yds.
     
  8. Engineering101

    Engineering101 Well-Known Member

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    Topshot – you stated verywell exactly what I’d be worried about with the chamber bedding and then Jud96 presents real world experience as to why it isn’t an issue. Sounds like it is every man for himself and do whatever appeals to you. Right now all of my rifles have barrels that float.

    Here is what I’m really thinking (I should have said this up front). Most of my rifles will group one or maybe two bullets at 1 inch or better at 200 yards. However, what most of my rifles won’t do is group a selection of bullet weights that well. For example in my 338 RUM the 210 TTSX consistently groups around 0.750” at 200 yards. But the 285 grain LRX is hanging around 2 inches. It seems like that rifle is naturally tuned to the 210 TTSX. I have other rifles that shoot heavy bullets the best but they aren’t so good with light bullets.

    If this chamber bedding method would make all bullets shoot good, it might be worth doing even if there is some risk of messing things up if you are not careful when shooting from field positions. What I’ve heard is that this method does just that – makes everything shoot better. However common sense tells me that may not be true because tuned means just that – it is optimized to a spot in a spectrum of choices.

    So my guess is that yes this does work but probably only for the bullet that you tune and bullets similar to that bullet. There is some value in that because it says I could tune every rifle for my favorite bullet insteading of using what happens to shoot the best. What do our gunsmiths say about this? Since you build rifles a certain way - chamber bedded or not - you must have a reason or two for what you do?
     
  9. Rocky Mountain

    Rocky Mountain Well-Known Member

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    Interesting way to tune a rifle only real way to see how well it works is to give it a go. The load would need a good ES to start with or it would still show vertical at loner ranger.
     
  10. AKGuide

    AKGuide Well-Known Member

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    This thread came up shortly after I removed the bedding from my chamber area. I spoke with many trustworthy folk about why some people bed the chamber and others don't and got different answers most of the time. With as heavy as my barrel is the smith I used put bedding under the chamber to help with support he said. This seems like the right thing to do from all the guys I spoke with regarding bedding. From my personal experience I removed the bedding and my vertical stringing went away. I shoot primarily from a bipod and my guess was that I was putting pressure on the barrel when shooting prone and when I was lucky enough to shoot off a make shift bench the vertical was less prevalent. So all in all I am glad that I tinkered around and completely free floated my barrel. The most important thing about bedding I truly believe is stress-free.

    Reuben