Need help with touch hole replacement

[squirejohn]

Well I finally got the old vent (hole enlarged too much) out and proceeded to replace it with another of the same size; 1/4 X 28). In the past I have replaced other style/size vents with no problem. The vent liners just screwed down into the barrel and could actually screw beyond the outside of the barrel. I'd just "unscrew" the liner until flush with the barrel.

This liner however has quite a shoulder or head that sticks up to about twice the depth of the screw slot for a total thickness of about 1/16". I tried reducing the diameter of the head, but the only way that will go into the barrel is if it's smaller in diameter than the vent liner hole - not a viable solution. There is no obstruction in the liner hole to prevent it from screwing all the way in.

The only solution seems to be is to screw the liner in as far as it will go and then grind it off flush with the barrel and touch up (brown) the barrel. However it appears as though the depth of the vent liner's 1/16" vent hole is only about as deep as the head which needs to be ground off in order to make the liner flush with the barrel. Beyond that the 1/16" hole opens up into a wide cavity. I may be wrong about the length of the 1/16" hole as I have no accurate way of measuring this. In any event it would be a very very small distance and I don't know if there is a minumum safe vent hole length or not. The vent liner is the 1/4 X 28 stainless sold by TOW. So my question is how should I procede? ::

 

[squirejohn]

PS The old vent liner did have a bit of a screw slot and if I ground this one off flush with the barrel it would go well beyond the screw slot Are/is there other vent liners that would "screw right in"?

 

[LRB]

My vent holes have about .030 to .032 fire channel. No problem.

 

[Birddog6]

Yes, there are several dif. 1/4 x 28 vent liners & they screw in the hole differently and the Shoulders on them are dif. diameters & depths & etc. Apparantly you don't have the same style as you took out.

 

[twobirds]

Is the shoulder on your vent tapered? If so, it is probably meant to be countersunk a bit. In which case you would use a countersinking tool (preferably in a drill press) to lightly countersink the hole you drilled in the barrel for the vent. You do not want to countersink too deeply - just so the vent will screw in to about the bottom of the screwdriver slot in the vent. Tighten snugly, then carefully file the top of the vent flush with the barrel. If you're not comfortable with this option, check other parts dealers. Some carry vents with different kinds of shoulders.

 

[squirejohn]

Thanks for the responses. I ordered a different style liner and that should do it - I hope.