12-12-2013, 08:48 AM
(This post was last modified: 12-12-2013, 08:52 AM by NugginFutz.)
With respect to the Upper Receiver Lapping tool, it should be noted that this tool has a precise fit. It needs to be caressed into place, and should not be forced, in any way. A little light lube on the pilot is a must. I've read a few reviews (MidwayUSA?) where some have said that it wouldn't slide into their uppers, so this leads me to think that either their uppers weren't to spec, or they had attempted to man-handle the tool into place. The main point, though, is that it is a precision fit, and it is quite easy to bind it up.
One should also be very careful to take it in very small steps, checking progress at frequent intervals. Obviously, you cannot replace lost material.
Klem: if you can afford to give me another month, or two, I can give you my impressions on the one barrel I bedded with Loctite Blue. It is a low end AR-Stoner 5.56 H-Bar, paired with a DPMS upper. This was the first build where I experienced what I consider a sloppy fit (barrel deflection amounted to approximately .5 degrees before torquing the nut). I had similar misgivings as yours but, after weighing the pros and cons, I went ahead and tried it. With an Aimpoint H1 micro, it is hitting 4" steel at 200 yards with no trouble, so accuracy seems to be decent enough. I intend to run a few hundred rounds before I break it down. At that time, I'll know the answer to the question that has been nagging me since I bedded the barrel. I have a bottle of propane standing by, just in case.
Either way it goes, I really don't count it as a great risk, considering the minimal investment I have in the barrel and upper.
One should also be very careful to take it in very small steps, checking progress at frequent intervals. Obviously, you cannot replace lost material.
Klem: if you can afford to give me another month, or two, I can give you my impressions on the one barrel I bedded with Loctite Blue. It is a low end AR-Stoner 5.56 H-Bar, paired with a DPMS upper. This was the first build where I experienced what I consider a sloppy fit (barrel deflection amounted to approximately .5 degrees before torquing the nut). I had similar misgivings as yours but, after weighing the pros and cons, I went ahead and tried it. With an Aimpoint H1 micro, it is hitting 4" steel at 200 yards with no trouble, so accuracy seems to be decent enough. I intend to run a few hundred rounds before I break it down. At that time, I'll know the answer to the question that has been nagging me since I bedded the barrel. I have a bottle of propane standing by, just in case.
Either way it goes, I really don't count it as a great risk, considering the minimal investment I have in the barrel and upper.