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.243 Win./Two Rifles/Diff. Chambers

RCrosbyRCrosby Member Posts: 3,808 ✭✭✭
My old .243, a now departed Ruger Ultralight, apparently had a tighter chamber than my present .243; an early Sako bolt.
Loads (all well below maximum) that were developed for the Ruger typically have a noticable amount of primer protrusion when fired in the Sako. I'm thinking this may indicate excess headspace. If so, do I just scrap this brass and start with new, or is there a way to get back to properly sized brass in my new chamber?

Comments

  • guntech59guntech59 Member Posts: 23,188 ✭✭✭
    edited November -1
    By firing them, they should now be fire-formed to your chamber. Neck size, load and go.

    But, if I were you, I would rework the load for the new rifle. Just my opinion.
  • nononsensenononsense Member Posts: 10,928 ✭✭✭✭
    edited November -1
    RCrosby,

    "...typically have a noticable amount of primer protrusion when fired in the Sako."

    If the primer is sticking out of the base of the case then you have a headspace problem especially if the primers didn't flatten out again. They are not fireformed if the primer is sticking out.

    I would take a neck sizing die and start with it backed off and neck a piece of brass down until it is just a little difficult to chamber with a stripped bolt. Now the brass will headspace off the false neck and you should be O.K. A little insurance can be added by seating the bullet out until it contacts the lands. The load for this needs to be a moderate load as you've added a source of pressure to process.

    Best.
  • RCrosbyRCrosby Member Posts: 3,808 ✭✭✭
    edited November -1
    guntech,
    gotcha on "redeveloping" loads. Soon as all this blessed white stuff leaves the ground and it's a bit easier to get to my range I'll be developing accuracy loads for my 58, 70 and 100 grain pills in the Sako.
    nononsense,
    Since these fired cases will enter the chamber easily before sizing I've blacked a neck and adjusted the sizing die to size just shy of the shoulder. Will try the long seated bullets with moderate loads.
    Thanks both!
  • RCrosbyRCrosby Member Posts: 3,808 ✭✭✭
    edited November -1
    Follow-up.
    Limited testing because getting to my back yard range still involves a bit of trekking through a couple feet of winters left over snow but:
    Took 6 of the cases with backed out primers; sized so the neck was about 90 % sized but the shoulder untouched, and loaded some 105 grain Speer soft points; 3 seated fairly deep and 3 seated out to beyond what the magazine would allow and just touching the rifling. With a moderate load all 6 seemed to be fine as far as primers not overly flattened but all absolutely flush with the base of the case. Proper sizing seems to have taken care of that problem, HOWEVER,
    All 6 round are clearly key-holing at 50 yards. As nearly as I can determine my L579 Sako has a 1 in 10 inch rate of twist. Does it sound reasonable that this barrel would not stabilize these bullets? I haven't been aware of keyholing with 100, 70 and 59 grain bullets but I'll have to go snow walking again to make sure.
  • nononsensenononsense Member Posts: 10,928 ✭✭✭✭
    edited November -1
    RCrosby,

    My list has the Sako factory original barrel with a 1:10" twist.

    Between the 'moderate' load, cool weather and a bullet with a length that is close to needing a faster twist because of the moderate load, you sure could have keyholing. Try increasing the load or switching powders. Make sure your barrel is clean including the throat area.

    Best.
  • RCrosbyRCrosby Member Posts: 3,808 ✭✭✭
    edited November -1
    May take me a while, but I will try what you suggest and let you know how it works out.
    Thanks!
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