[QUOTE=Peter Laidler;350465]I can tell you about the REAL difference between the .303" and 7.62mm extractors. It's all to do with the primary extraction. If you convert a .303" extractor to use in your 7.62 rifle, due to the geometry, the extractor will not grip the front edge of the thinner rim until primary extraction is almost complete.
Using the correct extractor means that as soon as you start to lift the bolt handle the re-designed 762 extractor will grip the rim sooner and you therefore get the CORRECT leverage and therefore perfect primary extraction. More to it than that of course./QUOTE]
Quite so, Peter.
My point is that the extractor which Numrich sells is NOT a drop in fit for a 2A rifle.
The two attached images hopefully show what I mean.
In the shot with the two boltheads, the top one is a 2A1 with Indian 7.62 extractor, while the bottom is a .303 bolthead with a Numrich extractor fitted. The shape of the head of the claw is very different, and is very close in size and shape to a No 4 7.62 extractor. This extractor, unmodified, will not allow a 2A1 bolt to close.
The second shot compares an Indian 7.62 extractor with a Australian .303 one.