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Posted By: murf205 Double grouping A-Bolt - 12/18/11
I have a friends 7mm Rem. A-bold Medallion that is shooting into two distinct groups, each one about 1 1/2" away from the other. They are pretty good groups--just not together. Tried 3 different loads(66 grs of H-4831, 154 Horn.)(67grs H-4831, 150 win Power Point) 67grs IMR 4831, 140 Nosler BT) and they all do this. The scope is a VXIII Leupy 3.5x10. Every thing is snug and I'm shooting w/no wind in 65 deg weather. The cronograph says nothing screwy is going on, spreads are not noticeable and the Primer is a Fed 215. Cases are trimmed to min. Any ideas.
Murf ( I wish they had named that law after someone else!)
Posted By: longshot3 Re: Double grouping A-Bolt - 12/18/11
Check your free float. I had the same thing happen to my new 243AI this year. Not sure how it happened during bedding, but I had one little spot touching the barrel, near the end of the forend. Took it off and, wah-la, problem solved!

Posted By: strut64 Re: Double grouping A-Bolt - 12/21/11
I have often heard that double grouping is a result of bedding problems. either the action or barrel may be your problem. Easiest to fix is to make sure the barrel is free floated. Good luck
Posted By: murf205 Re: Double grouping A-Bolt - 12/21/11
Well, it finally quit raining and I just got back from the range. The A-bolt just would'nt tolerate those loads as menntioned above. It would'nt shoot the 140 Nosler bt but it loves the 150 gr Ballistic Tip with 64.5grs of IMR 4831 for 3090 fps (5 shot ave.). The 140 was a tad warm @3370's so letting a little steam out of it probably helped, along with letting the barrel cool 15 min between shots. This rifle really likes a cold dirty barrel. thanks guys.
Murf
Posted By: tomme boy Re: Double grouping A-Bolt - 12/22/11
Head position. The paralax is not set right on the scope.
Posted By: Win_94 Re: Double grouping A-Bolt - 12/22/11
I had that problem before. Every once and a while the POI would change and group 2moa away from before.

The problem ended-up being the aluminum scope mount was damaged. Everything seemed tight and I couldn't tell something was amiss until I removed the rings.

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Posted By: murf205 Re: Double grouping A-Bolt - 12/22/11
Tomme Boy you are right. I had to unscrew the focus on that scope to get it to focus on my older eyes, and I knew that my much younger friend, would need to turn it back , so I did'nt lock the ring--presto! 2" paralax. Once I noticed that and screwed the locking ring out to meet the eyepiece, and tried the 150 gr Noslers, it went to shooting like an A-Bolt should(1"). It's amazing how the small things can make a test session go awry.
Murf
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