Hi guys, bed my .308 a while back, it would shoot decently, averaging about 0.75" groups. I started to mess around with my loads and one day got a few groups that vertically, were very tight, but had some horizontal stringing, about 1-1.5" across. Took the action out of the stock and noticed the bedding along the right edge of the action had a crack along it. If I left it alone, it looks like it'll stay put, but obviously wasn't secure, so I just plucked it off.

Not sure if this was the right thing to do, but I basically drilled a few holes in the stock that was now exposed and put some Devcon into that area, along the right edge of the existing bedding, plopped the action back in (after putting on shoe polish, etc). I then decided that since the rest of the bedding was left alone, I could go ahead and hand-tighten the action screws, locking the action down into the stock, resting on the existing bedding, since I was only touching up the right edge of the bedding.

Took it off, everything looked fine. NOticed the Devcon was squished towards the center of the bedded area when the action sat in the bedding during the process. Looked like a really thing coat, but there was Devcon there. I then proceeded to shoot it after a week or two using the same load and noticed the groupings had opened up a slight bit. Instead of that same vertical level in the 5-shot group, the group had opened up all around. I did notice that the right half (that had some new Devcon poured on it), the edge where it met the left half (old Devcon bed) would just BARELY catch if I ran my fingernail across it.

I then went home and opened up the rifle again, took some sandpaper and tried to smooth down that newly bedded area a little bit to be more flush with the left half of the original bedding area and it seems good. That barely catch between the two halves was now even smaller. Took it out to the range again, tried a few more loads, back to under an inch, around 0.75" groups of 5 shots. I still haven't been able to duplicate that same vertical closeness I got that one day though.

Any suggestions? Could that one or two tight vertical groups (but horizontal stringing) be a fluke, or maybe it was tight vertically because the bedding was cracked on the right edge and threw things off somehow while at the same time created the horizontal stringing? Or could it be that I need to fix the bedding again somehow. If I need to fix the bedding, would you guys suggest taking sandpaper and once again sanding down a little bit on the edge where the two halves meet, and a little of the new Devcon as well? Or would you say screw it and just re-bed the entire action? Assuming I need to re-bed the whole thing, how do I remove all that old Devcon?

Thanks guys, I really appreciate it.