Is that because of relatively small maps, or a tendency to use longer-ranged weaponry?

Had a game the other day that only lasted 4 turns.  We use the map size suggested in the rulebook.  We had some pretty long range weapons as well as strikers/seekers on both sides.

IMHO strikers-seekers-ammo are not really balanced for the length of our games.

-Tim

FWIW... ammo is point-costed based on an expectation (for the smallest ships) that you will get at least two shots out of a normal weapon. Thus, the ORAT for a weapon with one "shot" is 50% that of a normal weapon. For the largest ships, the expectation is that you'll get at least six shots out of your normal weapons.

Interestingly, some recent simulated battles seem to indicate that this is still OVER-costing weapons with ammo...

Most of the games I have played are decided withing 4-5 turns of "when the shooting starts", usually preceded by 2-3 turns of maneuvering for position. I've had a few games run longer, usually because of terrain or mission considerations, and had one game that ran something like 12 turns as both sides refused to die! I personally feel that the best thing to make games last longer and more interesting is to keep weapon ranges shorter. I would much rather have a bunch of ships constantly jockeying for position like a macro scale dogfight than a game where the two side sit on opposite sides of the map just pounding away with their respective super guns. I also have used the optional damage control rules and like the fact that while a bit random and wonky to some people, they do keep ships "in the fight" longer and generally make things more interesting to me at least.
Also, I have used ships with Ammo-dependent weapons and have not found them any more "unbalancing" than some of the trait combinations that have been highlighted by others. MadSeason and I played a short, enjoyable campaign in which he triumphed against my fleet which featured Ammo based main weapons. Maybe it says something about my "poor" design skills, but on more than one occasion my ships shot their magazines dry and were forced to try to battle on with their secondary armaments.   
I think the best advice for any players of Starmada is to play around with the system until you find what you (and your buddies) find enjoyable. If you want to impress the chicks with your super mega spinal mount destructor cannon mounted on a hull 25 battlewagon, great. On the other hand you may find that it is fun to play with lots of small to middling ships zipping all over.
Just my 2 cents,
Cheers,
Erik

Dan please notice that I said the "length of our games" and not everyone's games.  The last game I had my opponent's 700pt battleship took out my 961pt Battlecarrier (hull 16, armour plating, shields 5+) on turn 2.  He had a pair of [G] arc weapons that were RNG: 24 ACC:2+ IMP:4 DMG:2, Ignore shields, increased impact, continuing damage.  That boils down to about 8d6 damage per hit.  I was lucky not to die on turn 1 (he missed with one despite having fire control as well).

I think it comes down to how over-the-top-crazy people get with their weapons.  If you can reign the weapons in to something more akin to what is in the official starmada supplements I'm sure Ammo works out fine.  It can be broken though.  In the example above if he used ammo it could have taken out both my capital ships on turn 1!

Dan I'm not sure if you've ever considered it, but some it would be great for both new-comers and people-who-play-against-power-gamers if you came up with some "official tournament rules for starship construction" which would limit/restrict some of the nastier combinations you can get in the game - you know to promote longer games that are based on in game tactics rather than "winning by design".

Noted, although I'm not sure why it matters... I was only trying to explain the point-costing rationale.

I'm listening for any suggestions...

This, a thousand times.  This is the truth, unless somebody happens to make a really terrible tactical error, and even then sometimes.  This is almost exactly why my group eventually stopped playing 'mada.

And yeah...  Ammo is really, really good.  I once fielded two variants of a flotilla, one of which used ammo, and the other of which did not.  The non-ammo version mounted two torpedo tubes per ship, and served reliably but without acclaim.  The ammo version mounted 10 tubes per ship, each with one ammo, and earned great distinction (and a subsequent ban) when a squadron of them annihilated an undamaged battleship worth easily thrice their CRAT in one salvo (granted, they were done after that, but they had more than earned their keep).  And these were not fantastic weapons; range 12, RoF1, Imp1, Dam1, Double Range Mods, Slow Firing in the G arc.

Rule for exploiting ammo: Take any weapon that you want to hit the enemy with on turn 1.  Instead, mount five of them with ammo 1 each.  If the enemy is still standing after you fire them all, then you didn't use a big enough weapon.  You probably weren't going to get 5 turns of shooting, but you almost certainly will get one turn of shooting, and ammo lets you condense five turns of firing into one turn, at probably an ORAT cost of x2 or so, and the cost of not being able to fire those weapons again later...  which is only a penalty if conditions for firing them were going to get better (solution: inverted range mods), or if you were going to get more than 5 turns of shooting (improbable...).  This way you also get all the damage up-front, which means early systems damage, kills, and VP, which makes the rest of the game easier than if you had been firing once per turn for five turns, making ammo weapons significantly better than firing once per turn for five turns.  It's just bonkers good.  And once you get to hull >25, you're actually getting free ORAT for ammo (unless I'm misreading something...).

The trick there is that the more you use ammo, the shorter the game gets...  self-fulfilling prophecy.

I can't speak for others, but in reading up on the game online, the most common complaint I saw was that longest range weapons (be that 18 or 30) with traits like Ignores Shields and Double Inverse Range Mods were effectively impossible to beat without having exactly the same sort of options. I'm curious what you would do in terms of countering that particular strategy?

I, too, love these conversations, and really appreciate how accessible you are (quite so for me, as I'm in Commerce City, just up the road a piece, *and* I went to college with Admiral Drake).

What you say hinges on the idea that you know, going in, what your opponent has selected for weaponry. I agree that in any sensible game, that is reasonable. You allow for the fact that the enemy knows, to some degree, your tricks each of you have honed your technology and strategy against one another's defensive whetstones. I guess the lesson I'm taking is that the notion of "best or sneakiest build trumps tactics" is an artifact of allowing someone carte blanche and a CRAT budget instead of giving them some manner of framework to work within.

That said, what size maps do you play on, and with what average thrusts and ranges, as a rule of thumb?

I think another factor might be the "optional rules" people are using.  They may be exacerbating certain combos or strategies.  For instance we use only the basic movement - and I think that actually makes it a lot easier to be effective with "G" arc weapons - especially since moving backwards is so easy.

Cricket I agree that most things have a reasonable counter.  The problem in a tournament or campaign setting is that you don't have time to react to your opponents design, and if extreme enough no amount of tactics are going to help you overcome the design advantage.

The only two combos I have found that are pretty darn near broken are:

-Piercing +2/+3 with increased impact (gets you both if you have good or bad shields)

AND

-2+ accuracy, increased hits, repeating

I realize the increased traits are really hard to price because their effectiveness is linked to the probability of hitting/penetrating.   

To a lesser extent i think expensive seekers are too deadly.  I think the fighter traits have been priced kind of assuming that they only modified the "offensive portion" of the fighter.  For seekers/strikers I'm not sure this pans out because they really don't have to worry about defense very much.

-Tim