New barrel-problems ejecting 7mm Mag. cases

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by coyoteugly, Oct 9, 2012.

  1. coyoteugly

    coyoteugly Member

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    I recently had a new barrel put on a 7mm Rem. Mag. Previous reloaded ammunition was firing fine in the gun before I had the barrel change. Now, after firing the bolt will lift easy but I can't pull the bolt back to eject the cartridge. A couple taps with a plastic mallet and it will open. The gun is a late 70's model 700 ADL Remington.

    The loaded cases measure .508 just above the belt before firing. The fired cases measure .515 after firing. They are expanding .007 according to my math.

    Question: What is wrong? Head space to long? Bolt problems? Load too hot? (160 gr. Nosler Accubonds with 64.0 gr. H1000 seated 2.770" with Hornady Comparitor MV 2683 checked Sunday 10/7/12) I do not have the measurement to lands of the new chamber.

    I would appreciate your earliest responses as unfortunately our hunting season is upon us and I may be gunless for an elk unless I get this problem fixed. :) Thanks, Rick
     
  2. Joe King

    Joe King Well-Known Member

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    It sounds to me like you have a head space issue, I would be taking it back to the who ever installed the barrel along with the cases fired in that chamber and with some unloaded rounds. they'll likely have to cut off 1/2" or more to fix it if it is indeed head space. If that's the case I would also demand that they replace the barrel. That's a pretty mild load too.
     

  3. coyoteugly

    coyoteugly Member

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    Thanks Joe,
    Send some of your moisture south to us near Billings! I took the gun back to gunsmith last night and left it for him to look at. Asked him to call me before he puts too much into the situation. I tend to agree with your assumption that the head space is off somewhere. He told me he ran his Go-No Go and fired a round thru it before he gave it to me originally, and said it was good to go. Someone also told me .007" is not too much expansion on a 7mm fire case. others tell me it should be no more the .002-.003".
    I was hoping for more responses but guess either everyone is hunting, digging sugar beets, or taking a wolf trapping class. I'll let you know what I find out in the next couple days.
     
  4. Joe King

    Joe King Well-Known Member

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    Havre! moisture? lol. We only got enough to knock the dust down for a day or 2, it was good for the guys that got their winter wheat in though.
     
  5. AZShooter

    AZShooter Well-Known Member

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    Is the expanded area in front of the bolt shinier than the rest of the case body? Is there any other area that is shiny? If so you may have an area in the chamber that is larger in diameter than the surrounding area of the chamber. When this happens the bolt lift is normal but it won't move to the rear. In some instances the chamber can be polished up and the issue is solved. Let us know so someone can help unravel the mystery.
     
  6. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    Sometimes a belted round will have a slight burr right at the base of the body at the start of the belt. I've seen it on a ruger 7mag and a bit of oil and fine grit wet-or dry fixed it. I'd try new brass for now as the tail end isn't swelled at all yet and get your smith to touch up the chamber for you for free later.
     
  7. cowboy

    cowboy Well-Known Member

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    Did you have it re-barreled here in Blgs?
    Are you shooting reloads or factory?

    If your smith did shoot it as he said and there was no problem then
    it would lead me to think it was ammo related but it sure sounds like a head space or chamber problem to me.
     
  8. coyoteugly

    coyoteugly Member

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    Thanks for the thoughts and opinions gang. stopped and picked up gun last night. What gunsmith discovered was the bolt face, just in front of the lugs was out of round. He chucked the bolt up to true the approximate 1/4" and took about .006" (about 2/3 of the circumference) off to try and bring the bolt back into round. He also took the barrel off again, cleaned up the chamber face and polished the chamber while he was at it. He thinks the bolt has always been like this but with the new barrel it just became accentuated. He fired the gun and bolt lifted and opened properly. He placed a previously fired cases that were sticking, closed the bolt and they ejected properly.

    I have an exact model of gun in a .270 Win. caliber that he rebarreled last year that is a tack driver. When I got home I took calipers and checked for "round" in front of the lugs on it. Exactly .293" all the way around......so, I believe he did find the problem. I'm going to take 7mm Mag back to range this weekend and run it thru it's paces again to check it,

    He claims (and I've heard from others) Remington's have this problem right out of the box sometimes due to their craftsmanship. Could be why the gun was shooting quite erratic last couple years with the old barrel. Hope I got all the terminology correct and appreciate hearing from others to see if this makes sense to you all! I guess my only doubt in this situation is why hadn't this problem shown itself in the previous 33 years I owned and shot this gun? Hmmmm.......thanks
     
  9. AZShooter

    AZShooter Well-Known Member

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    Sounds there was a bind between the bolt and chamber in the new barrel. The factory barrel's chamber must have been a bit larger in diameter which kept it from binding. Very interesting. Thanks for sharing.

    I have seen three rifles in 30 yrs of handloading that had their bolt faces opened up for magnums and they were not opened up enough. That caused binding issues too. Hard bolt lift, hard removal or difficult feeding with a CRF were the symptoms.

    Now you will put this in your bag of tricks of things to remember and will most likely never see it again. The irony is that sometime in the future you'll encounter another new problem and be back at square one trying to figure it out.