remove this plz

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solskjear123

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I bought my Sako 85 finlight in 30-06 6 month ago
when i just bought it it shot one whole at 200m with SMK 175gr HPBT and 48gr H4895
last month it shot 6inch at 200m with the same loads

scope is a NIkon prostuff 3-9X with optilock mount and rings
nothing is changed except the brass fired one or two times more

i also tried some factory ammo they all result in larger groups than before

someone knows what is going on?
 
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Sounds like something has come loose, check the torque on everything even your scope and bases. If that doesnt show something replace the scope with a known good scope and try again.
 
The first suspect is a loose screw, either your rifle's action screws, or your scope or mount screws. So the first step is to ensure that all your mounting hardware screws are tight and torqued correctly, and that the action screws are correctly torqued. Ensure the ring mounts, or the bases, if you use bases that engage the dovetails, have engaged the dovetails correctly, and are tight on the dovetails. If necessary, lightly tap them forward with a non-marring hammer or a piece of wood or brass intervening between the mount and the hammer to ensure they are tight. If you find a loose screw, on either the scope mounts or the rifle, tighten it to the correct torque, then shoot for accuracy, and compare this group to your original groups.

If the mounting hardware all check out, or if you tighten the screws or the dovetail bases without an improvement in accuracy, the second suspect is a badly fouled bore. Spray the bore with brake clean to remove the surface layer of carbon, then use a good copper cutting solvent to get back to bare steel. Again, shoot for accuracy, and compare your results with your initial groups.

If that doesn't fix the problem, the scope is the weak link in the accuracy chain. Install a scope that has proven itself on another rifle, shoot the rifle for accuracy, and see if your groups are back to normal.

Beyond this, there might be an issue in the bedding, though how that could change without you being aware of it is a mystery. Remove the barreled action from the stock and ensure no foreign material has found its way into the barrel channel. Be sure the recoil lug properly engages it's recess in the receiver, I think SAKO now uses a floating recoil lug, but if not ensure that no crap has accumulated in the recoil lug recess. Examine the contact surfaces of the receiver and barrel for shiney spots which indicate movement. If found, the bedding is probably at fault, although looser action screws don't help. Be sure to reassemble the rifle correctly, paying close attention to the correct placement of the magazine box.
 
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As above , check torque on scope rings and mounts. Action screw torque also.

Check parallax in your scope. If there is parallax and its not adjustable set the scope in the rings forward enough that you see a dark shadow around the circumference of the image, this helps center the reticle and forces you to hold the rifle a consistent particular way.

Personally, if you find excessive (or any) parallax I'd dump the scope as inconsistent results will follow you where ever you go with that scope.
 
Check as the above responses pointed out, is something loose?
Then ask
How are your reloading? Full length resizing? Neck Sizing?
One thing to check is to make sure the shoulder is getting bumped back some, any amount for .001" and more is better than none. When you chamber a reloaded round, does the bolt close easy?
If the shoulder is making contact, it crushes each round being chambered which can cause groups to open up.

Also, was the weather considerably hotter this time around comparable to when is shot your tight groups on an earlier outing?
 
i dont use a torque wrench to torque the screws
i torque all screws to where i cant torque them anymore by hands

i dont think it is caused by scope, screws or bedding .

a friend said the chamber is enlarged by my hot loads
is it possible ?

i will try some other loads next week and keep this updated
 
"Also, was the weather considerably hotter this time around comparable to when is shot your tight groups on an earlier outing?"

yes weather is hotter
i bought in April this year
 
solskjear123 said:
i dont use a torque wrench to torque the screws
i torque all screws to where i cant torque them anymore by hands

i dont think it is caused by scope, screws or bedding .

a friend said the chamber is enlarged by my hot loads
is it possible ?

i will try some other loads next week and keep this updated
Click to expand...


Many are surprised how little 18-22 in/lbs is, which is recommended torque value for most rings.

Doubt you have any chamber issues due to 'hot' loads

Have you proven it is not the scope?

I have a Finnlight in 30-06 and it is a very consistent shooter with a well tuned rifle/scope and handloads. The worst case is 2moa with best been in the 0.7moa zone for 5 shot groups. With the 1:11 twist bullets greater than 180gr do not do as well as the lighter bullets.

Just modeled the generic QuickLoad load you have, 175 SMK and 48gr H4895. This load has a case fill of 85%, 51Kpsi, predicted velocity of 2640 fps, a powder to fast for the application but you are close to a node.

All in all , I suggest you use H4350 slightly compressed and check that scope.
 
Owned dozens of Sako's, and every one without exception shot hot loads best. I don't think you could be running anything hot enough to worry about expanding a chamber.
Check your shoulder when resizing to make sure it chambers easily after resized.

"yes weather is hotter
i bought in April this year"

Hotter weather with some powders can dramatically change your velocities, and change group size accordingly
 
Shooting conditions vary from day to day. That will be part of it for sure.

The other part can well be fouling. When you shot your first groups the barrel was new and free from fouling... you didn't mention anything about cleaning.
 
Check screws, rings, bases, action everything. If you're cleaning it constantly stop cleaning it, conversely if you aren't cleaning it then you should start. Basically do the opposite. Change the scope to one you know is good, or mount yours on a rifle that you know shoots. People are quick to say they don't think its the scope based on little more than they don't want it to be. Scopes break all the time.

The chances of the chamber being enlarged are practically nothing; unless you can remember a time that you sorta blew it up a little. ;)
 
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