RST 1 oz. "Lights" are very good and should suit for most upland shooting. I've been tempted to try their pheasant loads myself but so far only in my more modern repeaters. They are great for Western pheasant hunts I can tell you. If your London Steel barrels are original bores in good condition (as recommended above) the biggest hazard would probably be stock cracking and I'd stick to 1 oz. max. I wish RST made an 1-1/8 oz. field load... The good thing is they use magnum (hard) shot in all their loads (they told me) which makes the most out of an ounce of shot in the first place.