Since this is My 3rd post. Traditionally I believe, as a newb, I am supposed to explain how all of you are doing it wrong/how I am going to revolutionize the hobby, and or/how I am going to arm a life boat in 1/144 scale. Instead I am going to ask a question. I was reading about how shortening barrel length can effect performance, but the builder didn't want the barrels hanging over the side. Fast gun limits the length to less that 5" from the breech. Is it possible to lower the breech and use a bent barrel similar to a Big Gun cannon to maximize barrel length , but minimize how far the barrel protruded from the turret face? The first picture (gun-1) is one variety of fast gun cannon. The second picture (gun-2)show a canon with the breech lowered. (sorry picture order was changed when I posted) Other than making tweaking the guns more difficult, what drawbacks would this posses? It would seem well suited to smaller ships that need to keep weight low and minimize the above deck barrel length. The last part of my inquiry is more for big gun or battlestations. Is there a reason you could not use a bend that doubles back on itself (See 3rd Picture) to maximize barrel length? Torpedo tube could have a good length added and still not protrude from the side of the ship I have not sen anything similar being used on the forum, so my first guess is there is an inherent problems with the design? Please help me get my mind better wrapped around gun design. thanks, chris
Sure you're allowed to bend barrels, but you're still limited to 5 inches of barrel length. You'll lose some shot velocity, though depending on where the bend is and barrel length with a bend vs without a bend you might still see a net gain in some (rare) situations. (the closer the bend is to the breech and the shallower the bend the less impact you'll see, but you'll also gain less in overall barrel length.) Bends tend to decrease reliability (increased jams) which is also bad. (hint: reliability is a HUGE advantage, yet even a lot of vets lack it) Depending how hard the bb hits the barrel you'll dimple the barrel which tends to shorten it's life and cause your bbs to spray around a little more making it harder to hit your target. Any ship light enough for this to be a big concern will only have bow/stern guns which dont need as much velocity as a sidemount anyway since you really aren't shooting belows with them, that means you can get away with a shorter barrel and still not have any trouble poking holes in balsa. (it takes a lot more energy to push water out of the way before you get to balsa vs just pushing air out of the way) If your rookie ship is so weight sensitive that you really need to worry about barrel length you're probably making life too hard for yourself. I don't do big gun or treaty but that many bends in a barrel is really going to rob performance.
One thing to note here is fastgun cannons get most of their velocity from the split second of pressure that builds up behind the breech oring. Bending you barrel will, in most cases, break the straight trajectory and in doing so decrease your velocity. On the other hand, Big gun relies on barrel length and large flow to obtain the necessary velocity to puncture balsa. But, bending your barrels into big S shapes won't increase your hitting power. The increased friction and unsmooth flow path will decrease velocity significantly.
I have run "bent" for about 4 years now on two different boats and find them as good as straight in durability (I did not expect it to last but it does). Granted I only bend them at the breach and only 15 deg. but they hit hard and don't fail. I bend them so it fits in the turret easy and gives me room for foam in the turret cover so it floats.
In Battlestations you could bend the barrel, since the limit on barrel length is determined from the face of the turret to the end of the barrel. I believe it would be a lot more work with very little benefit. More work, because it can be hard to bend a barrel 90 degrees, let alone have 3 90 degree bends. Little benefit because Battlestations has a limit on how hard the guns can fire. With the standard Indiana design, I generally have to dial back pressure to pass the penetration tests, so having a longer barrel is not needed. Treaty has the same 5" maximum barrel length as fast gun, so no advantage to bending the barrel, except a little better scale appearance from not having a long barrel sticking out.
rcengr, I didn't think of the limit on penetration depth, thanks for the input. So in the end it would mostly be a lot of work for something cosmetic. thegeek, out of curiosity, what are your barrels made of?
I think he mills them from cosmetic reject Ferrari F1 engine blocks. Only one barrel from each block of course!
https://www.mcmaster.com/#standard-metal-tubing/=16nkrkr It won;t let me copy the page but I use 1/4" .035wall steel and it used to have a spec. like 4162? but I don't see that now on the web site.
