Headspacing a 40X

[BPTactical]

I have a 40X that doesn't ignite about 1 in 10 rounds. Sometimes it will ignite after a second strike. Tried three kinds of ammo, does it with all three so I assume it is the rifle and its a headspace issue? I took the bolt apart and made sure the firing ping and spring looked good. Who in Denver would be a good gunsmith to have work on it? I assume headspacing isn't something I can do with my duct tape and dremel tool.

What is 'head space' on a 22LR?

Headspace is a distance defined by the designer of the cartridge from a given point to the breech face. Different cartridges headspace in different ways. Some from a point on the shoulder, some from the mouth of the cartridge, some from the belt on the casing and some on the rim.
22lr headspaces on the rim, a rim SHOULD be .040 + .002-3 clearance to breech face would be ideal, but 22 varies all over the board, some as little as .036 to .044 (max HS should be .046)
As Hoser alluded to if you had excessive headspace you would have at the least bulged cases/blown out rims/blown out cases.
As long as your not blowing out rims/cases I would not be overly stressed.
If and it is a big if the headspace is excessive the only fix is setting the barrel back and rechambering or possibly fitting a new bolt.
Again Hoser is spot on(the man is wise), likely you have a mechanical issue. A sacked spring, worn firing pin, burr or debris is entirely possible.
I would be happy to take a look.