Originally Posted by
Mauser308
Shrinkage and material hardness vs outside temperature are two considerations, others are maximum sustained temperature exposure and chemical resistance. Compression strength is the other consideration (hot glue is poo).
Marine-tex and Devcon are about the same for chemical resistance when cured, JB weld is a little less so. Loctite two pack is pretty bloody good in this regard, but pricey.
Marine-tex is only rated to sustained temperature exposure of 120degC, which on suppressed rifles I wouldn't be surprised to see this limit getting a test or two especially a varmint gun. Who's touched a barrel and burned themselves haha?
Temperature stability once cured (thermal expansion and contraction) is another issue, quite often with a gun that's stuck together a trip into the freezer pops the bits apart. Marine-tex doesn't quote a value here but it's not expected to move between huge extremes of temp (being used near water is the key from the name?). Devcon and Loctite have figures for this, neither are good slightly better than aluminium and in the region of steel. Long-term dimensional stability at a fixed temperature is a nice figure to quote but in actual useage 3% shrinkage is way less than timber over time and likely similar to fibreglass used in stocks depending on the actual material used. Almost certainly better than plastic stocks - yuk.
Chemical resistance is another factor, but the epoxy is likely better than wood and in any event the bore chemicals and solvents shouldn't be allowed near the action screws etc...
On the subject of release agent - shoe polish? FFS...
LPS-3 wax spray preservative, about $28 a can and that will do basically all your firearms work for the next ten years including rust prevention. A light spray will prevent any epoxy I've seen from sticking, won't affect the cure, is food approved and smells nice to use. And will save you about 30 minutes in applying the release agent and will have a better job done at the end of it.
