Bizzare question about explosives! [Don't worry, I'm not trying to make a bomb! See below.]?

Most explosives work by a chemical reaction that creates a large amount of gas pressure very fast to split rock, destroy something etc. And, it is known that applying pressure will shift the equilibrium of a reaction that forms gases towards the side with the least number of moles of gas (reactants side in the case of explosives). If you were to make some kind of containment system that was so strong it could not be blown up (like some very very heavy-walled metal chamber; I'm talking several yards thick walls [or something like that]) and filled a relatively small cavity in it with TNT, PETN or similar explosive material so there was no void space whatsoever and hermetically sealed the chamber with some means whereby the "door" was just as strong as the walls so there was no way it could blow out and the charge was set off by remote control in some manner; would the material be able to explode? Or maybe a small portion, then the reaction would be quenched?