Anybody ever seen such a thing? I have a really tight clearance situation which can be addressed with a 1/2-20 x 1.75 socket head bolt and it ideally will be an AN bolt (short threads). Aircraft Spruce, McMaster and Pegasus all come up dry. I could possibly use a Grade 5 or 8 but it needs to be partially threaded and 1/2- 20 so I can use a jetnut.
Could you cut down a suitably partial thread bolt of a longer length?
I could, yes. The problem is finding something like it in the first place, the non threaded part needs to be ~1 1/4", it has to have an Allen head so I can get real close to something because there's not going to be room for a socket over a hex head, 1/2-20 so I can use a self locking jetnut (like I said clearance is tight fo' sho' 
) and strong since it's a shock eye bolt in double shear.
I'd like to find something premade so it won't be prone to rust where I would have to cut one.
In reply to Curmudgeon:
Have you tried Fastenal?
Not yet, but in the past I have not had a lot of success with them.
See if you can find a local hardware store that stocks either Midwest Fasteners or Hillman Fasteners. I know they used to have that size but am not sure about the thread length. Get the hardware store to check their catalog.
Edit: Checked Midwest's online catalog they list one that size in chrome (#79905) and a 2" standard one (#32884) Not all of their assortments are listed online so check the store.
http://www.boltdepot.com/Socket_cap_Alloy_steel_black_oil_finish_1_2-20.aspx
The tricky part will be figuring out which bolt has the non-threaded shank length you're looking for, then cut it down?
Do you really need a bolt? Could it be a high-strength clevis pin?
If the fastener really needs to be in tension, I would look into a shoulder bolt. Like this.
Mike, PM sent
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