Barrel wore out?

Discussion in 'Gunsmithing' started by spitfire_er, Dec 18, 2011.

  1. spitfire_er

    spitfire_er Well-Known Member

    Messages:
    130
    Joined:
    Aug 2, 2009
    Long story short. I built another rifle (one for the wife this time) and used a FREE used barrel of unknown history. Re-cut the chamber, re-threaded and put a new crown on it. Only reason I used it, well other than being free, visually the rifling looks strong and super clean. I don't have a bore scope, but the bore measured .237" and .243" if I recall.

    That being said, it is a 1-10" twist finished at 21" chambered in .243 Win, .655" at the muzzle. We shot the first couple "groups" with it yesterday with dismal results.

    I hand load all my own ammo, but I had an old box of Federal premium with 95gr Noslers. Box says 3,030 fps, so with the shorter barrel, I'm assuming it's up at least 2,850-2,900 fps.

    So here is the problem. I checked the entire rifle over, everything was tight and clean. Fully bedded and floated. Yet, those 95's didn't stablize. Shot 5 shots down range with about a 6" pattern. Walked down to find oval holes.

    All of my other 10" barrels have handled these bullets without a problem. I'm going to try some lighter bullets to see what happens, but this has me thinking that maybe my Free barrel is JUNK!

    I don't know, Any ideas?
     
    Last edited: Dec 18, 2011
  2. J E Custom

    J E Custom Well-Known Member

    Messages:
    7,312
    Joined:
    Jul 29, 2004
    Factory barrels are notorious for being finicky.

    Sounds like the lands and grooves are fine so just try different loads. Start with one load and
    have different primers then try the best primer and different bullets(Don't get tricky with seating
    depths) seat to magazine length - .020. repeat the process with different powders @ approximately
    the same velocity using the best bullet and primer you found.

    This should get you a reasonable load to work with and change one thing at a time while you are
    fine tuning the load.

    Clean between each test load so they are in the same conditions(Cool Clean Barrel).

    If it is a sporter weight barrel, #3 or smaller you may have to place a small amount of tip
    pressure between the barrel and stock. (Poster board, cracker box, ETC)

    Don't give up.

    J E CUSTOM
     

  3. Loner

    Loner Well-Known Member

    Messages:
    599
    Joined:
    Apr 14, 2010
    Did you ball mic the end of the bore. An inch off and a recrown is probably in order. And
    a 1:10 is marginal for a 95 grain. My sako is over an inch with them and frequently
    one holes with 85's and 75's. With the short barrel and lower speed they may never
    stabilize. But check the muzzle end size and a new crown first.
     
  4. spitfire_er

    spitfire_er Well-Known Member

    Messages:
    130
    Joined:
    Aug 2, 2009
    Thanks guys. The barrel was a custom take off, but not sure of what manufacturer. I re-did the barrel like a new barrel would be done, that's half the reason it ended up so short.

    The measurement was also taken at the muzzle end, so I'm assuming both the muzzle and the bore diameters are good to go. Also ample room was taken off for a new clean chamber on that end.

    Sounds like I first suspected that I need to shoot a little lighter bullet, and do some more load development. I just needed a few second opinions.


    thanks again.