I'm with CJ here, both of the ones you pictured should go (= agree with his rule of thumb). 1/8" should be plenty. I've muscled balls in that were almost impossible to tell if they were behind the knuckle, just because I doubted (gut instinct rather than eyesight) they would go in either corner. But one can't position the cue ball at much of an angle (the OB is not supposed to glance off), with CJ there, too. But I'll try them on the super-tight Dynamics (old EPBF standard) where I'm instructing tonight.
Greetings from Switzerland, David.
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„J'ai gâché vingt ans de mes plus belles années au billard. Si c'était à refaire, je recommencerais.“ – Roger Conti
I agree....it makes a big difference in where you position the cue ball as to how much you can force it through the point....and you do have to "muscle" it in with a quick draw stroke. I've made those that look impossible, but you have to stroke it or it won't go.
Where are you in Switzerland David? My sister lives in Geneva.