why my ltm-m adapter is selectively working?

[guoshuo]

I recently got a 50 hex 2.4 ltm, use it on my m3 with a 5 dollar ltm-m adapter which works well with my elmar 50mm 3.5 and jupiter8. but for the hex, at infinity the focus patch image doesn't collapse with the vf image, the lens needs to recede further to make focus collapse but it can't. I measure the thickness of the outer rim of the adapter, it's about 0.9-1mm. a weird thing is that all these 3 lenses collapse at infinity on my ltm body zorki-4. what is happening here? will simply buying a good adapter solve this? thanks for your advice.