Switch over to Green Dot (if you can find some). It's better for the heavier loads in terms of felt recoil and wear and tear on your equipment. Keep the Red Dot on the bench for 16s and doubles. If you actually are loading 19.1 grains of Red Dot, it won't be long before someone will be telling you your "loads sure are noisy". Good Luck.
What kind of hull are you using? With 1 1/8 oz of shot, 19 grains would be on the hot side for a tapered walled hull, like a Win or a Rem. But it would be middle of the road for a straight walled hull, like a Fed or Euro hull. My rule of thumb with Red Dot is to not exceed 18 gr. in a tapered walled hull with 1 1/8 oz of shot. If you want a faster load, go to a bit slower powder, such as Green Dot, WSH or International.
I'm loading 18.2 grains of Red Dot with DR 1118 wad and Win 209 primer with 1 1/8 oz of shot in a AA hull. Chronoed at 1250. The chrono used is said to measure just a bit high when measuring shotshells. My book says 18 grains RD in a AA should give 1200 fps. Pressure is 10,400 psi. According to the Alliant reloaders guide.
I took one of my loads apart last night..... checked to make sure of components, put it back together and loaded 4 more just like it.... 19 grains of Red Dot etc.
Had a bit of sun this morning to go with the 21°F and grabbed my Chrony and drove to the range. I used two factory 1200fps shells to get a correction number and then ran the 5 reloads through.
Average was 1215fps, sample size is small and my powder is old stock. I suppose new powder could be different and the hulls were once fired Nitro 27.
MG makes a good point on checking your components, and a simple check on your chronograph is to fire a few factory through it. Not exact but easy to do... Larry
Nebs, from the wilderness backwoods of Eastern Oregon this is the process I use to insure I am at least close. Kinda like "horseshoes", I am suspecting that close counts.
STS, Nitro27 and Federal GM I am told are at least 3 of the shells used at most all registered shoots and are 3 that I have access to. I use them. I normally use the GM. Just tore one apart for grins and giggles, x grains of Green Dot which is the same as I found last time I tore one down (maybe a year ago)..... Box indicates 1200fps, I duplicated the load and did the chronograph thing at that time. It was perhaps May or maybe end of April, I remember the temp was in the mid 50's. My reloads were within plus or minus 8 fps for a total spread of 16fps and the factory rounds were within 15fps of Lyman 5th edition information. Best I can do here but on some loads with Vectan AS I have relied on information on shells sent in for actual testing. My observations have been that the actual test rounds were not that much different than what my Chrony came up with. Again, sample size is small, results are only mine. Larry
Another one for you Wadcrusher, Duplicate of Estate/Made in France white box.
19.3 Vectan AS
Fed GM Case (or original Estate)
492 gr of shot.
Same numbers on chronograph as my Red Dot load in the Nitro27 hull but cleaner in the bore. Larry