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View Full Version : Shot Placement Creep



mcase1
04-10-2017, 05:49 PM
I hope this tale helps someone else that encounters this problem.

I've been shooting a Savage 10 -T tactical .308 from Cabelas for a while now. I mated it with a 30 mm vortex viper tactical milradian 1-16x 44 scope. The scope was mounted with UTC heavy tactical rings on the factory installed Picatinny rail.

For a long time now I have been chasing an accuracy issue. Despite cleaning and allowing the barrel to cool, my shot placement would always begin to move a LITTLE bit (about 1/2" to an 1" at 200 yds.) after thirty or so rounds. I would click the scope a tenth of a Mil and the rifle would group great, sometimes it would just widen the same hole at 100 yds. So I got to figure its not the rifle. Maybe loose rings? I tightened them past recommended torque and it would still happen but - just a LITTLE bit and always toward the end of shooting.

Well I figured it might be the scope, but is was so little that it could easily have been my shooting getting stale as well. So I thought I'd take it all apart and start again. Here's what I found. The UTC tactical rings while very beefy have a small rod (Not a square bar) that sits between the notches on the picatinny rail and which in theory should - when placed against the forward end of the notch - rest against the rail's ridges and preclude forward movement. However, the UTC rod was insufficiently deep and was of course round. Instead of engaging the Picatinny rail's ridge and stopping forward creep it instead actually dug into the top corner of the ridge deforming it. This would allow the scope to creep SLOWLY forward damaging the the rail ridge as it did so.

Well, I carefully filed the notches square again to get rid of the indent made by the UTC scope ring's rod. I then bought GOOD expensive rings - Burris Xtreme Tactical - which have a squared bar that sits deep in the notch and fully engages the whole face the ridges on the Picatinny rail. Problem solved.

The rifle now places shots with uniform accuracy throughout my whole shooting session. So yeah, its true buy REALLY GOOD rings in the first place. If they are meant for a Picatinny rail, check that they have a deep flat bar to engage the rail notches. My Savage tactical shoots the lights out. Its heavy varmint barrel stands up through continued shooting. Its deserves really good rings. Lesson learned.

s3silver
05-01-2017, 11:54 PM
Thank you for sharing this. It's good to hear real life reports and how the issue was mitigated.

65Whelen
05-02-2017, 08:47 AM
Good advise, a lot of the times it's the little details get overlooked.