Model 99 inconsistency -- HELP

[eaw7nc]

My favorite deer rifle in the safe is ill. This is my model 99c in .300, It will not group at 100yds anymore. The first shot is 12 o,clock 2" high, then the next will move to 2 o,clock 3" out, then the next shot will drop to 4 or 5 o,clock 6" low. It will follow the pattern fairly closely day to day. This gun in the past has shot nickel sized groups for the past 10 years.  I have been told to shim the forearm screw, any more advice. This gun is is an old friend and I really want keep it going.
Thanks to all in advance
Eddie Williams
Manteo, NC

[Ron T.]

You didn't say, but I'm guessing you've got a scope mounted on your Model 99.

I had a similiar experience in the fall of 2007 and it turned out that two of the scope mount screws suddenly loosened up after many, many years of use and many hundreds of shots going down the barrel.

I couldn't believe it when I removed the scope and checked the scope mount screws in the mount under the scope... and found the two front screws both loose !!!

Once I tightened them back up, my rifle went back to shooting an average of .75 inch 3-shot groups at 100 yards.

The only other thing I can think of which would suddenly effect a rifle's accuracy so drastically would be that someone damaged the crown on the barrel's muzzle.

Of course, all of this assumes your scope is working properly... i.e., make sure your scope's crosshair hasn't been displaced.   


Strength & Honor...

Ron T.

[eaw7nc]

Hey Ron
The crown on the muzzle end is good, smooth, bright, and no nicks. I have not had the scope off in 2 years, I will check and report back.
Thanks
Eddie

[Blowtorch53]

eaw,

I agree with Ron T.  It's the scope mount screws, mounts, or scope.  Probably loose.  Chances are the scope has not gone bad in the safe.  I have a bad habit of my big arse overtightening screws in the mounts and then they shoot loose and break off after I fire a few shots on a new rifle.  Then I have to go in the range office and get it fixed at three times the price that I would have paid them to mount the scope in the first place.  Lessons learned!  My .300 shoots like yours used to and it's older then me.  I'm old!

Blowtorch

[eaw7nc]

Hey BT
That' the way I'm working now. I have a new set of mounts ordered and shopping for a new scope. I have a Simmons now and want to upgrade.
What do ya'll know about the forearm mounting? I have been told to set a shim under the fore arm and re-tighten the screw. I'm not sure about about this and feel bedding would be a better option.
I don't know how old you are BT but my .300 is older than I am and I'm 54 years young according to my bride of 28 years.
Stay Well and Warm
Eaw7nc

[Ron T.]

I would fix what is wrong and change NOTHING else.

I don't know why you'd be told to "shim" anything.  Whatever has happened to your accuracy can be brought back to "normal" again by reversing whatever happened.  I'm still betting it's the scope mount screws or possibly the scope's crosshairs have gotten loose... and are moving around inside the scope.  I've seen that happen as well, but that's a rare happening, but also a possible reason for the poor accuracy.

I'd first check the scope mount screws for tightness.

As a last resort, I'd install new mounts... but I doubt that the scope mounts, themselves, are the problem.  Scope mounts do NOT "wear out".

Good luck!!!   I know how frustrating such problems can get... most of us have had to go through such problems with our "pet" rifles as well.  Such things can and do happen if you hunt long enough with the same rifle. 

I had one of the scope mount screws break off causing a 2nd mount screw to loosen up after many years of use on my Model 70 in .338 Win. Mag. that I bought in 1961.  I had the front scope mount screws loosen up on the scope mount of my 1953 Model 99 Savage in .300 Savage caliber (the forerunner of the .308 Winchester cartridge) I bought as a replacement for the Model 70 (just too much recoil for an aging hunter who likes to do a bit of bench-rest shooting in the off-season) which I can shoot all day long off the "bench". 

The Model 99's scope mount screws loosened up after many, many years of having the same scope mounted on the rifle and literally HUNDREDS of rounds shot down the barrel.

As you can see, these things just "happen", but don't go off "half-cocked" and make a bunch of changes in your rifle... i.e., don't "fix" what ain't broke.  If you change things that aren't the original problem, you may end up making your fine rifle LESS accurate than it would have otherwise been had you simply tightened up the scope's mounting screws (if that is the actual problem).   


Strength & Honor...

Ron T.