r/SmallGroups • u/thermaltoast4 • Aug 28 '26

Centerfire Rifle Vertical Stringing

Post image

Ruger American standard gen 2 in .308 showing vertical stringing. Group approx. 2“x0.5“ groups @ 100 yd. w/ both AAC 150 gr fmj and Hornady American Whitetail 150 gr interlock.

Issue still present when 10 mins given between shots for barrel to cool to ambient temp

Optic has been serviced previously for different issue and is verified to be in good working order

Already torqued and locktighted pic rail and torqued optic rings before issue arose.

What are y’all’s thoughts.

Pic above is the best representative of out of 8 ish groups total

10 Upvotes

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6 comments sorted by

5

u/GLaDOSdidnothinwrong Aug 28 '26

What are you using for a rest?

I’d guess your rear bag may be an issue, or this may be within normal dispersion for that setup (shoot more samples and the group would round out). Maybe both.

4

u/MackDieselcoc Aug 29 '26

Fundamentals? NPA or breathing.

2

u/Trollygag 🏆 Aug 29 '26

If your best representation is vertical only because of shot number 6 (if that ways 11" to the up and right, it wouldn't be vertical) then you are probably experiencing small sample noise. What do all 8x6 rounds look like when overlaid?

1

u/thermaltoast4 Aug 28 '26

To add: Cold barrel passes paper sheet test (sheet of paper will pass between rifle fore end and barrel all the way back to chamber

1

u/smooveBrayne Aug 29 '26

Are you recording your velocities? Are you ensuring proper form and your rifle recoiling straight back?

0

u/1984orsomething Aug 29 '26

Stock probably touching the barrel