Need some screws.

[Brdad1125]

Does any know the mounting screw sizes for rear sight and under rib on a T/C Hawken barrell. Just knowing if threads are NPT or Metric would help.

 

[Brdad1125]

anyone

 

[drpatton]

 

[drpatton]

https://www.muzzleloadingforum.com/threads/screw-sizes-for-tc-hawken.63689/

 

[451whitworth]

The rear sight screws are 6-48, meaning a #6 machine screw with 48 threads per inch. I haven't had an under rib off a barrel in years. T/C used standard USA gun screw thread pitches and sizes like 8-40 and 6-48. I have to ask though, NPT? Lol

 

[Brdad1125]

Thanks for the info. When do decending bolt sizes change from npt? Thought a 1/2 inch bolt and a 1/2 inch nipple have the same threads.

 

[451whitworth]

NPT or National Pipe Thread is used in plumbing (obviously) and certain automotive and industrial applications usually involving liquid transfer. Pipe threads also have a taper in them. That's how they seal up tight to prevent leaks with a little thread dope. UNF (United Nation Fine) and UNC (coarse) are the standard USA/SAE sizes for bolts, i.e. like 1/4-20 (coarse 20 threads per inch) or 1/4-28 (fine). The coarse/fine are the bolts you will find at the hardware store. USA made firearms generally speaking use EF (extra fine) threads that are not usually found at the hardware store. Even machine shop supply warehouses sometimes have to special order gun thread tooling. Our thread standardization was pushed/adopted during WW2 so the USA, Canada, UK could bolt on parts built in each other's countries.

 

[Brdad1125]

https://www.muzzleloadingforum.com/threads/screw-sizes-for-tc-hawken.63689/

NPT or National Pipe Thread is used in plumbing (obviously) and certain automotive and industrial applications usually involving liquid transfer. Pipe threads also have a taper in them. That's how they seal up tight to prevent leaks with a little thread dope. UNF (United Nation Fine) and UNC (coarse) are the standard USA/SAE sizes for bolts, i.e. like 1/4-20 (coarse 20 threads per inch) or 1/4-28 (fine). The coarse/fine are the bolts you will find at the hardware store. USA made firearms generally speaking use EF (extra fine) threads that are not usually found at the hardware store. Even machine shop supply warehouses sometimes have to special order gun thread tooling. Our thread standardization was pushed/adopted during WW2 so the USA, Canada, UK could bolt on parts built in each other's countries.

Thanks for the info. Glad to still learn something at 75. Trying to replace an Ivestarms barrel with a T/C. I bought T/C off of ebay . New, disassembled, and missing all small screws. Investarms screws must be metric as they wont fit. I found cleanout plug online but haven't located screws.

 

[451whitworth]

Investarms screws must be metric as they wont fit. I found cleanout plug online but haven't located screws.

Correct, Euro and Jap firearms use metric

 

[Brdad1125]

Hey 451, Do you know length of screws? I located some #6-48s.

 

[451whitworth]

.155"

 

[Brdad1125]

Thanks

 

[Lowrider76]

Does any know the mounting screw sizes for rear sight and under rib on a T/C Hawken barrell. Just knowing if threads are NPT or Metric would help.

ACE Hardware, in the gun screws section of nuts & bolts

 

[Brdad1125]

Thanks. I'll give it a shot.

 

[reubj]

McMaster Carr has most anything you might need.

 

[Brdad1125]

Sounds good. Will check it out. Thanks.