We used some pretty gigantic apertures on some of the Number 4s and still hit 18-inch bulls at 600 yards with issue ammo.
Thing about aperture sights is that they are easy to look through. That is important. You sight and shoot with both eyes open, no squinting. It's very easy. Your EYE will automatically look through the centre of the aperture, so all YOU have to do is put the front sight where the bullet is to go. Download yourself a copy of SHOOT TO LIVE from the MKLon this site. It came out in 1944 and it is STILL the best book on shooting military rifles with iron aperture sights.
Chck the barrel length before you start looking for a sight. That's important, too, so we know WHICH sight to look for. There are more than just a few of them.
Threaded firing-pin: VERY early. I have one on a sportered rifle I have here; the stock is marked prominently, "1906".
PARTS for these old ones can be very hard to find. The good part is that there ARE a few people who have some. With luck, one might pop up here and let you know. If it were my rifle, I would PM Wheaty and ask if he could help. He knows a lot of Ross people and he is in a part of Canadawith a lot more collectors than out here in the boonies.
There is another thread on the go right now about a 1905 Ross. Fellow has a problem with csings coming out 'way oversized. This is common especially on the very early 1905s. See his thread: there IS a cure for the problem.... and it's cheaper than you might think.
Have fun!
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