Put into production in 3053, Kallon Industries' Penetrator heavy battlemech was a product of the Federated Commonwealth’s frantic rearmament program in the aftermath of the Tukayyid truce. I have commented in the past how the AFFC clearly decided to spend their way out of trouble and the Penetrator is exactly the kind of tough, effective and affordable machine the Spheroid powers needed in order to field the numbers required to stand up to the Clan Juggernaut.
According to Technical readout 3055, the Penetrator is based on the Blackhawk Prime, which makes very little sense to me as the Penetrator is 50% bigger, 25% slower, lacks an XL engine and the weapons disposition is completely different - but hey, they both carry loads of lasers so that must be it!
The basic Penetrator entirely eschews using advanced construction materials, so a fair amount of weight ends up committed to the engine and chassis. However, that does mean it’s cheap to build, tough and easy to repair. A maximum speed of 64 km/h is very much par for the course for a seventy five ton machine, but the 120 meter jump range makes for good mobility at a time when jumping heavy mechs were perhaps not quite as ubiquitous as they are now. Thirteen tons of standard plate means the armour is respectable, although some way short of the maximum that can be carried on a mech this size. Of particular notice is that the rear side armour can be stripped by a Clan medium laser or penetrated by an IS large, which is not ideal for a mech that clearly wants to brawl - although the centre torso has no such problems. Also the combined frontal protection for the side torsos falls just short of being able to survive four PPC hits, which is a useful threshold to meet but seeing as the torsos are carrying close to maximum protection already, this is obviously an area where you can’t have your cake and eat it.
The Penetrator’s defences are augmented by an Anti-Missile System installed in the centre torso. This is fed by a single ton of ammo which is also centre torso mounted, just to keep you on your toes. Personally I don’t hate AMS and the ammo placement is justifiable on the grounds that it’s the best crit-packed location on the mech, but until it fires for the first time there’s exactly enough explosive power tucked into that ammo bomb to gut the centre torso in one go. Personally I’d have spent that tonnage on a heat sink and a bit more armour…
For weaponry, the PTR-4D has an ER large laser in each arm for jousting at range (and defending your rear, the arms can be flipped) and there are six medium pulse lasers split between the side torsos. Now I’m not normally a fan of the Inner Sphere Medium pulse laser, but they are weapon with a niche and the Penetrator exploits that niche well. This is a machine that wants to single mindedly close in to knife fighting range then remorselessly let fly with six streams of high energy photons until there is nothing left of you but a gently steaming pile of slag. As such, the 4D is really very easy to use - baby’s first bracket-firer, if you will. Close with the enemy firing the ER Larges until you reach 120 metres then switch to the pulses and never look back. So long as you drop a weapon occasionally to cover movement heat and the AMS triggering, you can’t really go wrong. However, having only twelve double heatsinks means trying to use the two batteries together isn’t really possible without immediately suffering significant penalties. Further, the presence of the AMS means you can’t just go bonkers with the heat curve and hope you luck out with shutdown rolls - even a standing alpha strike will put you at significant risk of an ammo explosion.
Famously, in 3056 the legend that is Kai Allard-Liao piloted a stock PTR-4D through a series of duels on Solaris VII. If my memory serves me right in one match he exploited the Penetrator’s confusing (for which read hideous) appearance to trick somebody over in which direction the mech was moving, causing them to jump right in front of his pulse laser battery believing they were attacking his rear armour. Considering the machine’s strange looks and quirky leg configuration, that’s a story I can believe.
The first variant is officially supposed to deal with the 4D’s heat issues but ultimately turns into quite a different beast. The PTR-4F replaces the ER Large Lasers with a pair of LRM 10s and loses two of the pulse lasers in favour of Artemis IV and a ton of ammo for each launcher. In one sense this is a wholly successful modification - you can now very readily fire all the weapons together with only a little overheat - but the way the range bands of the missiles and the pulse lasers overlap means I struggle to imagine why you’d want to. Unfortunately the 4F does not have the throw weight to be a potent long ranged missile boat, nor the kind of crushing short ranged firepower you want from a brawler - however the 4F does make a reasonable bodyguard for machines like Archers and Longbows that lack short range firepower of their own.
The PTR-6M takes a rather more straightforward approach to improving the Penetrator's heat curve by pulling two of the pulse lasers and a ton of armour and fitting five more heat sinks. Mission accomplished, we can now fire all our lasers with only a modest over heat - but that’s barely any more firepower than the six medium pulses we could fire whilst staying heat neutral before - and we gave up a ton of armour to achieve that? The 6M does at least have lots of heat sinks filling up the torsos, but I still think I'd rather stick with the original 4D if it's all the same with you...
The PTR-6S opts to mount a Guardian ECM along with the basic 4D weapon suite, but rather than replacing the AMS system (the obvious and logical choice) the armour is again thinned, this time down to just eleven and a half tons. On the bright side, this isn’t a terrible interdictor if you want to mess up somebodies C3 network - especially if they’re relying on Artemis equipped LRMs on their long ranged machines - but dropping this much armour from a machine that could have probably done with a bit more in the first place and lacks the speed to compensate doesn’t strike me as a particularly good idea.
As the civil war rumbled on, much more advanced Penetrator took to the field. Fundamentally a pretty simple upgrade to the 4D, the PTR-6T replaces all the Medium pulse lasers with ER mediums and used the six tons released to mount a targeting computer and two extra heat sinks. At long range this is pretty much win-win. Your large lasers are more accurate and you’ll stay cool when you fire them whether you walk, run or jump. However at point blank range you’re less accurate whilst doing less damage and generating more heat for your trouble. Between 90 and 240 meters things get a lot more interesting as the choice between a single large and half your battery of mediums gets a lot less clear cut. The best way to juggle your heat curve and targeting numbers at any given point in time will vary, but it’s worth remembering you can fire one large and three mediums while walking and stay cool. Ultimately, the combination of accurate and intense laser fire combined with zombie toughness makes the PTR-6T a real beast of a machine.
Around this time Major General Archer Christifori of the AFFC put together a customised version of the basic PTR-4D, which traded in the ER Large Lasers for Clan-tech equivalents. Obvious upgrade is obvious, but one can hardly argue with the power of clan lasers - I bet he wishes he could have scrounged enough pulse lasers to complete the set.
With the destruction of Kallon Industries Talon factory in 3069, it looked like the end of the line for the Penetrator series, but some 60 years after the it first entered service, a sixth and final variant returned the battlefields of the Dark age. In 3105, Kallon Industries gained control of remains of the ex-Shengli Arms factory on Victoria. The factory had been destroyed to deny it to the Federated Suns, but it was reconstructed by 3115 and set to work manufacturing a new model of Penetrator. The PTR-7D is structurally quite a different beastie to its predecessors, using endo-steel, laser reflective armour and enhanced arm actuators. The ER large lasers have been replaced by Snub nosed PPCs so short ranged firepower is enhanced at the cost of significant reduction in capability beyond 390 metres. Unfortunately I haven't had the opportunity to run this version myself, so I'll allow you to draw your own conclusions about how that combination of parts sound, but I will observe that reflective armour doesn't seem such a hot idea on a mech that optimally wants to fight the enemy in a telephone booth.
As is probably obvious by now, if your opponent puts a Penetrator in front of you you're in for a tough time tearing it down. Even the variants that skim off armour are respectably durable with only the AMS ammo in the centre torso as an ever present Achilles heel, whilst the 4D, 4F and 6T are legitimately heavily armoured (although the 4F is carrying around LRM ammo without CASE protection, which is actually a bit unforgivable in a standard engine machine with a couple too many heat sinks).
The 4D, 6M and 6S want to fight at close range and their long ranged firepower isn’t anything much to shout about, so given the choice you want to try and pick them apart at range. On the other hand, the 4F prefers to fight from a distance and its short ranged firepower is much less worrisome, so closing with that one is the order of the day. Basically know your enemy and do the thing he doesn't want to do - however, 6T is pretty happy fighting at any range, and that makes it the most unpredictable and difficult to deal with.
I can't help but feel the Penetrator must have been one of the most common Heavy mechs in the AFFC throughout the clan invasion and civil war. A very large number of notable pilots seem to have ridden Penetrators throughout the years so they've certainly made their mark in all corners of the Inner Sphere as well as on the Pentagon worlds. In summary, it's sort of the Sherman Tank of battlemechs - a simple and serviceable machine well suited to mass production for a rapidly expanding army of freshly trained soldiers - and believe me, the Penetrator is a great mech to assign to a green mechwarrior if you want them to survive and contribute meaningfully to a lance.
Kallon Industries undoubtedly produced huge numbers of this workmanlike but effective machine in their Talon factory and the reconstruction of the Victoria plant coupled with the existence of the 7D variant implies they will be cranking out Penetrators for a good few years to come.