Dan R (from the WWCC) is joining the Cal-Neva club, and is building HMS Ramillies. He has a double stern gun that he has made fire pompom style, one barrel at a time. He intends to fire by rapidly moving the stick forward and back (the other guns are sidemounts, so those will be right and left) firing one gun, then the other. This means he can fire 100 rounds off the stern in 100 shots. Standard double stern cannons fire both guns together, so 100 rounds are fired in 50 shots. Is there any advantage to this, or is it a disadvantage to not fire both guns together?
Well the advantage here is that he will be a little more conservative and spread his shots more. The big disadvantage here is that by splitting his fire he is actually reducing the effectivness of his stern guns. Toggling is time consuming and not very accurate. You can't blow large holes by toggling the same way that a simultaneous firing of rounds can create. You can't fire as fast either. 2 rounds hitting the same spot side by side is definitly going to create a larger hole hopefully below the waterline to cause rapid flooding. It's easier to fire mulitply guns with one activation then to fire independently.
Yeah, what Curt said. If he's doing it because he is using one servo to fire both guns with poppet valves, I could understand it, but no real combat advantage I can see.
Yeah, The only reason I can think to do this is he can't fire both shots at the same time with the air speed/pressure his guns have.
I also don't see the advantage, I have a cruiser that could have a dual stern setup, I remember someone else iin my club (either Bob Pottle or Curt I think) telling me that if I wanted I could set it up so that they fire slightly apart, but still with one push of the stick. That seems complicated though, I recommend blasting away with both at once unless he's trying to be the last man on the water with ammo.
So, firing two cannons at the same time is more likely to cause more damage. Is this extra damage in the form of two holes from firing two balls, or is it rather the dreaded "chunk" or "rip" from two shots hitting right next to each other? I know that in big gun, triple cannons will beat double cannons any day, and quads are even better, because the extra barrels make nasty rips and chunks more likely. Dan is adapting a big gun cannon design for faster firing. He is using a modified MJV-2 "Arizona" design, and firing pompom style will hopefully reduce the chance of his regulator freezing while allowing him to get a decent rate of fire. I'm still dubious about it, so I'll be on hand with video camera to catch his sink
Another factor to consider here is not just the impacts but the condition of the hull skin is in. I have seen tripple and dual hits on fresh balsa that creates individual holes and eventually the gaping maw. However I have seen single rounds rip out large uneven chunks of hull paneling because the hull has mostly patch work and not enough balsa.The Ambroid or Sigment if used makes the area brittle and hard. When hit by multiple shots the effect is quite nasty ..large sections are torn out and not cleanly.
I think for damage, I would fire both together. The damage done by the two holes as apposed to singularly is much better. During this year's Canadian Nationals in Nova Scotia, our most feared Allied was the Warspite with her dual sterns wreaking havoc on Yamato's and Sharnroast's balsa. The video afterwards spoke for itself. I am rebuilding the Mogador with a dual half unit spurt cannon. Both set to fire seperate, but, if I was doing single shots than both would fire together. Newfoundland, being refitted by another member will try dual sterns. The damage is simply more impressive and you get the satisfaction of showing a little teeth in combat.
A good compromise is setting your stern guns so one fires when the stick is pulled backwards, and the other when the stick is pulled to the left (or right, makes no difference) This allows you to fire individually if you want to be conservative. If you pull the stick diagonally however, BOTH guns fire, and you get the effect of duals. He'd have to set up one of his sidemounts to fire off the forward stick, but it might be worth him looking into if the ability to fire single is desired at all. That's how I intend to set up the dual sterns on my Salt Lake City. Mike D
Normally, the servo actuates a MAV-3 or SMAV-3 which leads to MPA-3 actuators to fire the cannons. Dan is using the servo to directly actuate the main MJV-2 valve of a big gun style Arizona gun. He has a servo between the two stern cannons so when it rotates one direction it fires one, the other way fires the second. I don't know why he chose to do that, as it is never done in big gun, but it doesn't allow him to fire both at the same time. I think you've got a much better system for single fire.
