Posts: 560
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Just wondering if anyone has had this issue? And what tolerance range you experienced on a .750 gas block?
Gas block inside dimension is .744
Barrel outside dimension is .749
Will be contacting vendor on Monday both came from same vendor so hopefully it will be an easy gas block replacement.
Posts: 4,287
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I haven’t heard of this before, barrel sounds right, gb not so much. Definitely give the vendor/seller a call.
"Down the floor, out the door, Go Brandon Go!!!!!"
Posts: 8,507
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Those are good to lap for a press-fit.
The problem with the builder market is that manufacturers are left with 2 choices:
1. Make a gas block that will seal like the TDP calls for, so that no gas leaks from the union of the block and journal.
2. Make a gas block that any home builder can simply slide on and mount in place with an easy method.
If you notice the Mil-Spec FSB, it uses taper pins. As you pound in the taper pins, what happens?
The top inside of the FSB rings pull down against the top outside of the barrel, providing a secure gas seal for the system.
This is probably one of the most overlooked hinge points of reliability with home builders.
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