Would you fire this rifle?

[nvshooter]

On another board, I read that at least two members wrote that the metric thread on a Tikka receiver can have a 1.000-16UNF (or 1.0625-16UNF) thread on an American-made barrel threaded into it and torqued into place. Rather than getting into an argument over there, I'll ask here "How can two differing threads be trusted to contain the pressure of a high-pressure round being fired?" I mean would you fire that rifle, knowing the two threads in question are not compatible? I'm light-years from being very smart, but I'd suspect stripped threads on the barrel, in the receiver mouth, or in both places.

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[11Charlie]

My question would be why would any smart man mix thread pattern's

 

[nvshooter]

My question would be why would any smart man mix thread patterns?

Essentially mine, too. But there were two posts from two alleged "machinists" and fabricators," both of who said such a mixing would be just fine. I'm dumb as paint, but it would seem to me that mixing threads is asking to strip-out one or both. On a barrel, it's expensive. On a receiver, it's grounds for scourging and subsequent crucifixion...

 

[SubRosa]

It sounds like two smiths describing the same thing, albeit one is more accurate @ .062 over.

This may be normal.

SubRosa

 

[nvshooter]

It sounds like two smiths describing the same thing, albeit one is more accurate @ .062 over.

I'm going to assume the Tikka has a 26mm thread, which is 1.0236 inches OD. That's almost 1/40th of an inch too large for a 1.000-16UNF and 0.0389" too small for a 1.0625-16UNF. To a lamebrain like me, I'm just not seeing where the twain shall meet.

I'm not going to go into the pitch of the metric thread, which at 1.00mm would be 0.03937 inches between crests. 0.03937 inches is a lot less the 0.0625-- it's over 0.023 inches less. Maybe I'm dumb as a box of rocks, but I just don't see how the two can ever fit together tightly enough to put sufficient torque on them to serve the purpose of the discussion. There seems to be too much in dimensional differences to ever make it work. I'm no gunsmith, so what do I know?

This has been just something I saw over on one of my other firearms-related message boards. I didn't want to get into a urinating contest over there, so I figgered I'd discuss it here where no one would get exercised because no one here has a dog in the fight.