Next, observations regarding the RAR and escaping gas "around" the bolt...

The fat bolt on the RAR "seems" to act as a baffle. OEH had a good point about the gaps between the bolt body and rear of the receiver (first pic below). These gaps could still allow hot gas to sneak past to the shooter. But it still seems much more substantial than the T3 in regards to blocking the flow of gas in this area. RAR has the fat bolt, the T3 has a gap covered by the plastic shroud. No scientific proof, just an observation.

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