lugs 30 and 31 as seen in fig6 and correspondingly on the lugs 28 and 29 are partly bevelled surfaces located for minimum clearance around the nose cone surface e in fig3 this can be seen most clearly in fig6 where the surfaces e 39 are extensions of the nose cone rearward to the region of fig6 in the twisting assembly and disassembly of the point on the nose these inward beveled surfaces of the lugs must clear the nose cone and extension surfaces e and e 39 by combining the flat tall point ears of fig3 7 with the circular socket nose cone cross section i arranged for space outside of this inward boundary for point ear lugs of adequate size in the specific invention the inward beveled surfaces 34 35 of the ear lugs actually are arcuate but satisfactory function could be achieved with straight bevels referring to fig5 in the preferred construction the pair of forwardly facing lug walls 36 and 37 together are portions of an arcuate surface for tightening engagement with longitudinally spaced areas of the concave rear edge 38 of the pin 21 only one pair of lugs engage the pin on any given assembly the other pair being for the purpose of allowing installation of the point in 180 u00b0.