accuracy .308 problem

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Scorch

New member
found one srew on the mount base to be stripped/doesnt want to turn any more only turns around and around but doesnt tighten
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lt dan-
Have the base screws inspected. If it is just a stripped screw, replace all the screws and loc-tite them in place. If the hole is stripped, have all the base mounting screws drilled and tapped a size larger. One loose screw would have exactly the effect you are seeing. If your gunsmith doesn't find it, point it out to him. Just get it fixed.
 
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guntotin_fool

New member
Shot stringing is based on heat moving the barrel, if there is some pressure, then as the barrel "grows" the pressure point changes and the shots move, If you shoot five shots, and the same pattern happens, that is, two on target, then two or three off to one side with a growing error, what happens if you leave the rifle alone for two hours in the shade and then shoot again? IF the rifle returns zero to the original on target point of impact, then the problem is pressure on the barrel somewhere.

If the shots DO NOT return to zero after a few hours or overnight, then the issue is the sights or scope. With a stripped hole, that may also change how the action expands with heat. reweld the hole, re drill, and retap it is the only cure.
 
4

44 AMP

Staff
I discussed your problem with a friend today...

And he came up with something I had not thought of. Since you reported that the boresighter showed the crosshairs had moved after 3-4 shots, and at the time we assumed the scope/bases were not moving, then the end of the barrel is.

He asked it perhaps, the barrel had taken a hard knock against someting in the past? Not enough to visibly bend it, but maybe enough to leave a small dent in the metal. The compressed metal in a dent, even one too small to have any effect on the bore of the barrel, could have an effect on how the barrel vibrates, and how it flexes as it heats up. It is possibly that since your first two shots go together, they generate enough heat in the barrel so that followup shots are "flung" to one side or the other as the barrel vibrates/flexes unevenly due to a dent. It could be very small, and still have an effect on your group sizes.

Anyway, this is one more thing to check out.

I see from your recent post you have found a stripped screw in the mounts. The mount may still seem "tight" to finger pressure, but under the sharp jolt of recoil, could be flexing, as it is no longer being held evenly tight by both screws.

Let us know how things turn out, and good luck.

and of course, you're welcome.
 
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lt dan

New member
i am going to copy all the sugestions i read on this thread i think somewhere someone must be right. i told the smith about the stripped screw and he will investigate. i dont think i will get the rifle back soon as it is the hight of the hunting season over here and any gunsmith is on high demand. thanks for all the help i will keep you all informed.

i hope this guy gets my rifle fixed, otherwise i have a problem since i am having a rifle custom build by him at a price of $2700 without scope and sling.

he bedded the 308, lowered the scope, redid the stock blued the barrel removed the sights installed a new trigger and safety and took the rifle to the shooting range. and according to him put 12 shots(shelf ammo) in quick sucsesion into a hole 1 and quarter inch for this i paid $272. this excludes the round trip to the city of 400km.
 
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lt dan

New member
feedback. i got my 308 from the gunsmith again. he showed me the target he shot at. one grouping was just less than an inch and the second was even smaller. he said the problem was that the screws on the bottom back mount of the scope were not tightening the base of the mounts as tight as it is supposed to. he drilled bigger holes and put in bigger screws. he then shot the groups as mentioned.

i still need to confirm these groupings on my own.

p.s he now made this barrel completely free floating.
 
S

Slamfire

New member
Loose sights will just ruin what could be a good group. One of the first things to check is mechanical tightness.
 
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ndking1126

New member
and the people rejoiced!

400km round trip.. wowzers! If my math is correct, that's a little over 120 miles one way. I would have asked to shoot it at his range before I left :)
 
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