Dave-
I am not a shotgun shell reloader (but that may have to change), so you have a real advantage here. As far as pressures are concerned, you need to be in your own comfort zone. There are many qualified folks here when it comes to building good low pressure, low recoil loads for these vintage doubles.
In my case, because I am shooting damascus, prudence dictates that I use the lowest pressure loads I can find and the 7/8oz Federal from Midway with an advertised pressure of 5,000psi fits the bill. Recoil isn't too bad either.
Even if the damascus on my Meriden can handle more pressure, or if shooting your gun with fluid steel barrels why push our luck with hard recoiling loads? Have you ever noticed how many of these old double guns (particularly LC Smith) have cracked stocks? Wood is the weakest part of many of these older shotguns. So far my Meriden's stock is fine (no cracking whatsoever near the side plates) and I would very much like to keep it that way.
The 7/8oz loads perform remarkably well in the tightly choked Meriden on trap and no doubt play a substantial part in keeping recoil and pressures to a minimum. The velocity is fast (which helps cope the slower lock time of a hammer gun) and because these guns are tightly choked, you will find few holes in your patterns, even with 7/8oz.
Last Saturday with the Meriden and the 7/8oz loads I managed to score back to back 22/25, and the 6 missed targets out of 50 were not the gun or load's fault...totally me (4 were very easy straight away shots where I simply shot too quickly).
Your Meriden is a shotgun that the more you look at it and the more you use it the more it will grow on you. It is purpose built with form following function, and you should find it works well.
Happy shooting-
Doug
