Cooey No.10A aperture sight for .22 SMLE

I've got a couple of these and know that the Canadians officially fitted them to Patt'14 No.2 and No.2 MkIV .22 trainers to simulate aperture sighted rifles like the P14 and No.4. However, there is a reference in Skennerton's The Lee Enfield that they were very popular for Service Rifle and small-bore rifle competitions between the wars. Does this mean that they were used on .303 SMLE's? This would give the user quite an advantage with windage and elevation adjustment and a sight base that was considerably longer but the whole thing is held on by an extended ejection screw - fine for the .22LR but not sure about .303 recoil.

Haven't tried one on a .303 but if the fit is good around the charger bridge I wouldn't expect any problems from recoil. I'm sure the sights worked well in their intended use as training aids but I'm skeptical about their value in competition. They're definitely not in the same league as PH sights.

I had one for my 1907 no1 ie no charger bridge, enfield and liked the look of it very much. I decided not to fit it as it required some metal to be removed from the sight to allow the bolt to move underneath it. The windage adjuster on these has a very very fine thread and on mine it had been squashed so it didn't quite work right.
The attachment seemed Ok as the fit around the shapes on the receiver was fairly precise.
I decided to pass.