Threaded drill bit help

[Jamie Aust]

Hi All.
Some time ago I got some threaded drill bits from The Yard Store and Avery. At the time I didnt have the Angle drill as I was going to use a friends. These are all 1/4 28 thread. I have now, a used angle drill, but the bits I have are loose in the drill chuck. The diameter of the threaded end ( drill chuck) is bigger than the drill bits I have.
I dont seem to be able to find any ref to Diameter to order some sort of adaptor to fit inside my angle drill to change down to the size bits I have.

Any help would be great.

 

[KTM520guy]

The drill you have is threaded 5/16-24 (I think). One size up from 1/4-28. I also have an angle drill that size but alas no bits. If anybody knows where I can get 5/16-24 threaded drills, I would love to hear from you.

 

[Jamie Aust]

The drill you have is threaded 5/16-24 (I think). One size up from 1/4-28. .

The thread looks to be the same 1/4 28. its just the diameter of the threaded end is much bigger.

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\\\\\ This is the normal size
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\\\\\\\\
\\\\\\\\ This is the end that is bigger / need to reduce.
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[KTM520guy]

Just flipping through an old U.S. tool catalog I find that there is also a 9/32-40 drill size.