HELP!! Ruger 77, 7mm Remington Mag

Discussion in 'Long Range Hunting & Shooting' started by deadeye2, Sep 7, 2003.

  1. deadeye2

    deadeye2 Member

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    O. K. guys, first let me say that I do not claim to be a gunsmith, but I have always been able to get all the rifles that I shoot or have worked on to shoot a three shot group at 100 yds that was one inch or under. A friend brought his Ruger 77, 7 mm Remington Mag to me last fall. He wanted me to work up load for it and tune it as needed. I messed with that Ruger off and on for a LONG month. I could not get it to stop throwing the second or third shot! I was to the point that I wanted to break it over the shooting bench!!! Below you can find listed the things that I have tried. Oh yea, he wants me to try again this fall, I had hoped he would trade it off! I am out of ideas !

    1.) Bedding tried: Bedded action floated barrel, then full bedded it. I could see little or no improvement between these two methods. I then tried a little pressure between the forearm and the barrel. When I did this the groups did go wild !

    2.) Trigger: Crisp 32 oz.

    3.) Scope and mounts: The bases are tight and loctite was used. The scope is a Redfield 3x9. I wondered if it was the problem so I sent it to OBS and it checked out O.K. I also have tried this rifle using my Leupold VXIII, 4 1/2X14, the problem was still there using the Leupold. The scope is level to the rifle for sure.

    Ammo, I used hand loads only.

    1.) Powders tried: H4350, IMR4350, H4831, IMR4831, R22 and R19.

    2.) Primers tried: Winchester WLR, Remington 9 ½, Federal 215, Federal 215 match, and CCI 250.

    3.) Brass tried: All brass was full length sized and trimmed to 4.490” before loading. Remington, Hornady, Federal, and Winchester.

    4.) Bullets tried: He wanted to shoot 160 gr bullets, so I have not tried any lighter weights. Both Nosler Ballistic tip, and Partition 160 gr. Hornady Interlock and SST 160 gr. Barnes X 160 gr.

    5.) C.O.L.: I first seated the bullets .10/1000 off the lands. I tried moving the depth of seating up and back.

    I need advice. I must be missing something!!!
    web page

    [ 09-07-2003: Message edited by: deadeye2 ]
     
  2. Brent

    Brent Well-Known Member

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    A few questions, but first I'd like to say that all my Rugers and my buddies have all shot well under MOA with very little trouble at all, so Ruger does make accurate rifles, and they all seem to be comparably faster barrels than most as well.


    Is there ANY imperfections on the crown?

    Is there any pattern to the fliers, all high, left etc?

    Using windage adjustable, and or dovetail rings? I can't remember if the older M77's had the "good" dovetails in the reciever or not.

    Are case necks producing zero runout on fired cases?

    You can fire a 10-20 round group with the caseheads marked and indexed "up" in the chamber, reload them and do it again. If the group is tight and round on the second group and has fliers on the first, the boltface is likely out of square and is the culprit.

    You might use a match bullet to get it shooting first, at least you'd know you've reasonably done everything you can as far as bullet consistancy go.
     

  3. remingtonman_25_06

    remingtonman_25_06 Well-Known Member

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    Well I will be the first to say I love Ruger rifles. There is more Rugers in my house then all others combined. I have been able to get them all to shoot 1 inch or less 3 shots at 100 yards with its preferred load. So I to know Ruger makes accurate rifles. My 25/06 was a out of the box Ruger and was my actual first LR rifle to me. YOu pretty much have tried everything, maybe it just isn't going to be a shooter is the only thing I can think of. I would say sell it or rebarrel in 7 Mag.
     
  4. dbhostler

    dbhostler Well-Known Member

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    Don't feel so bad, a local old timer gunsmith built a custom .22-250 with match everything. He couldn't get this gun to shoot no matter what he did, and over the course of about two years, I think he gave up. Then on the other hand, he barreled up a rusty junk Jap action that was fitted to a wood stock and this rifle would one hole all day long with just about any bullet/powder combo.
    If all else fails, send the weapon and ammo to Brent and see what he can do with it. [​IMG] [​IMG] [​IMG]
    db
     
  5. Brent

    Brent Well-Known Member

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    db,
    Right after you. [​IMG] [​IMG]

    For me, I can't really say I've tested a bullet-powder-primer-oal combination entirely without having put anywhere from 100-200rds of them through the barrel. But I usually pick a bullet or three and use the powder I want because I figure all my barrels have been more picky about bullets that they ever were powders. After about 4-500rds I'm pretty confident in what the gun is actually capable of, still another powder and or primer with the best bullet I've found may tighten groups even more. I'm pretty basic, systematic and slow about my load development routine. Not much enjoyment in it except for the fact I'm getting a better and better load each time, and when the load is chosen it will be one made in confidence. I have to say I've had more problematic and finniky rifles than I've ever had easy ones.

    If it isn't a load consistancy proplem, it's something mechanical... and harmonics or the barrel if not mechanical.
     
  6. bblaine2k

    bblaine2k Well-Known Member

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    Jun 25, 2003
    deadeye2,

    Check your brass a little more closely, that's a good cause of flyers. Problems include:

    1.) Not squaring your resizing die. When you full length resize, you need to place a perfectly flat washer between the shellholder and the sizing die. Raise the ram up to the die then screw the locking ring down on the press. This takes the slop out of the threads of the die which can ever so slightly curve your brass just enough to cause flyers.

    2.) Are you deburring the flash hole? The little hole that the primer sends a flame through is often punched through with a pin, leaving a burr on the inside of the case which can alter the way the flame is thrown into the powder in turn causing flyers. Simply get a de-burr tool to remove the burrs.

    3.) Brass is inherently different from one piece to the next. We reloaders get brass from the factory that produces the brass from SEVERAL machines. Each has ever so slightly different tolerances. By weighing and matching up the brass into lots you can keep the brass closer to one another in consistency - same goes for bullets and primers

    Hope this gives you something to think about and helps solve the problem. Best of luck!

    Good shooting!
     
  7. Mark_in_utah

    Mark_in_utah Well-Known Member

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    Jul 30, 2003
    My 7 mag only likes 150 grain Sierra Gamekings. The others won't get better than 1 1/4" patterns. The 150 grain Sierras using IMR4831 and CCI 250 primers give me a 5/8" pattern. Try the Sierras and see what you can get.

    Mark in Utah
     
  8. Pigslayer

    Pigslayer New Member

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    Nov 20, 2011
    Been using both Hornaday 154gr flat base & 162 gr SBT in my Ruger 77, 7MM mag. for several years. Never really got the group I wanted at 100yds. Always used Sierra SBT's in my Ruger 77, .270 Win. with tack driving accuracy. The same with my 57 year old .270 Win. Remington pump.
    I have a box of .284 Sierra SBT's in 150gr. sitting on the shelf. Gonna give 'em a whirl. Don't know why I didn't use them before 'cause Sierras always performed well in any rifle or pistol I've loaded for.
    Does anyone have any input on on starting loads for this bullet in this caliber? Always been a big fan of either H4831 or IMR4831.gun)
     
  9. Sully2

    Sully2 Well-Known Member

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    Try a box of factory loads and see if it does the same
     
  10. Pigslayer

    Pigslayer New Member

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    Lord! I haven't bought a box of factory loads in say . . . fourty years! Whenever I got a new rifle or pistol I bought the makings to reload the ammo & went from there. Gonna try these Sierra 150gr. SBT's first. It's not that the rifle dosen't shoot in the "dead" zone at 100 yrds., it's just that I want a tighter group than 1 1/2". But I will keep your suggestion in mind . . . believe me.:cool:
     
  11. angus-5024

    angus-5024 Well-Known Member

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    im betting that the barrels twist rate is better suited to rather lighter or heavier bullets than just the 160's.
     
  12. WildRose

    WildRose Well-Known Member

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    My best performing loads for my old 7mm mag were H-870 and H-1000 using hornady 140gr interlocks and interbonds. Always used the cci magnum primers.

    H-1000 at around 72-74gr gave me one hole accuracy and very good velocities from both my Mod 700 and Win Mod 70 as well as my buddy's Ruger.

    72gr is approaching the listed max so start where you feel comfortable and work up from there.

    Question on your bedding. Did you bed the lug recess so it's a good tight fit?

    If not that can create just enough free play to cause that second round flyer.