[Ultra-Tech] Bioplas Guns?
 

A search didn't find prior discussions of this, but would Smart Bioplastic (UT170) be a suitable material to make firearms out of? Normal modern plastic typically can't handle the pressures generated by high-power firearms, but bioplas is a lot stronger - indeed, the stats from "Ultra-Tech Armor Design" (Pyramid #3/96) has it being nearly 10x stronger than TL 8 Ultra-Strength Steel (from "Cutting Edge Armor Design," Pyramid #3/85) against threats other than burn and pi (which it's 3x as effective against), weighing in at 0.045 lb per DR per square foot, while US steel weighs in at 0.35 lb per DR per square foot.

If doable, there would be many advantages of bioplas guns. Their self-repairing nature would likely reduce maintenance requirements. Their high DR/lb implies they may be able to be made lighter - although given the role of firearm weight in recoil mitigation, perhaps it would be better if they weren't made any lighter. They would be readily collapsible, making use of their nature as memory materials, making them easy to conceal and carry around. Indeed, the thing that made me think about if they'd be doable was the idea of a weapon that can change size to fit the user's needs, ranging from a (heavy) handgun up to a longarm with a stock. They may be more readily able to be 3D printed or similar. They would theoretically be able to pass through metal detectors undetected, but being legally required to include some metal would avoid that, and there may be some components that still call for metal*.

Of course, a lot of those advantages, in addition to being great for PC's, might make them rather attractive to criminals (easier to conceal thanks to a reduced Holdout penalty when collapsed**, ease of 3D printing means not having to go through an FFL or similar, and lack of a need for metal means they can potentially get past metal detectors and the like), so a reduced LC might be appropriate.

One serious drawback I can see to using bioplas is that, if I'm calculating things right, it appears that it has roughly 1/10th the weight of steel. That means, if shooting for the same weight as a conventional firearm, you're looking at needing a barrel, bolt, etc (the parts of modern firearms that must be made of metal) that take up roughly 10x as much volume, and I'm not certain how achievable that is without having a bulky, awkward mess of a weapon on your hands.


*The bullets are an obvious one here. Ceramic bullets would potentially be doable, but would probably have low damage due to their density and be frangible; bioplas bullets might also be an option, still suffering reduced damage but probably not frangible.

**Heck, you could probably design a bioplas firearm to look like something innocuous when collapsed.

Re: [Ultra-Tech] Bioplas Guns?
 

Depends on properties that are unspecified in UT. Certainly, any parts of a gun that can normally be made of wood or plastic can also be made of bioplas, but plastics don't generally tolerate direct contact with flame (i.e. propellant gases) very well, and they're usually not very hard so they'll erode quickly.

Re: [Ultra-Tech] Bioplas Guns?
 

Bioplas is explicitly resistant to flame (it gets x3 DR vs burn - or, rather, full DR vs burn/pi and x1/3 against everything else) and is self-repairing, so long-term erosion shouldn't be an issue. And it can get hard enough to serve as brass knuckles (Karatands, UT163), and possibly even enough to form and hold an edge, although that may require a modified form of bioplas (Bio-Tech has Polykeratin that can turn into a blade, but only in the form of TL 10 implants). But if it's not durable enough in the short-term, it may be that the barrels need to be smoothbore. Or maybe they can be rifled, but after a few shots the rifling is worn down and it becomes smoothbore, with lower Acc; considering this would probably represent less than 1 HP of Injury to the weapon, and that bioplas items regenerate 1 HP every 6 hours, the rifling may be able to recover in an hour or two.

EDIT: Of course, if the above won't work, given bioplas' high resistance to damage I think I have another option to have a collapsible barrel. Make the barrel out of metal of the minimum length, then make several more barrels of the same length and cut them in half long-ways. The extra barrels would be able to wrap around the original. Then, when you need to extend the barrel, the bioplas basically moves it into position and then wraps around to seal it. With the bioplas not being in direct contact with the bullet and propellant gases, there's no risk of erosion (the metal is all that's in contact). Something like this would probably work best with something that can manage variable output (use lower output when it's pistol-length, higher output when it's rifle-length) such as liquid propellant, electrothermal kinetic (ETK), or electromagnetic.

Re: [Ultra-Tech] Bioplas Guns?
 

Sure, assuming its heat stable and isn't so brittle that it fractures due to chamber pressure.

I see no reason why you couldn't come up with some bioplas firearms, except for the fact that lower weight realistically means higher Rcl unless you come up with some advanced recoil reduction system (e.g., a counterweight shooting forward just before the gun fires, like on some modern artillery).

Bioplas weapons are likely to have an early advantage at evading sensors, but presumably sensor technology will catch up, limiting bonuses to evade scans.

It wouldn't reduce the need for cleaning, however, and if the bioplas isn't as rugged as metal or ultratech ceramics, there might be a limit to the number of consecutive shots you can fire before the gun needs to "heal." You can push the limits, but at a risk of your gun blowing up. For a UT gun, there would probably be a smart sensor system to detect material failures, however, and possibly an auto shutdown beyond a certain failure percentage.

You could base this idea on the Cannibal Nanotech gadgets from Ultratech as well as magical/superscience convertible gadgets.


You could build them like modern automobile engines are built, with a few critical parts like the barrel being made of rugged metal or ceramics surrounding by bioplas (taking the place of the aluminum engine block). Legal bioplas guns might be required to have some non-bioplas parts for safety or sensor detection. You wouldn't get quite the weight and space savings as pure bioplas, however.

Clay bullets were used historically, but quickly abandoned for the reasons you mentioned. There's no reason why you couldn't have self-forging bullets made from high density bioplas or liquid metal, however. Even the ability to alter bullet shape would be an advantage for shooters, since you could program the gun to shoot any mix of AP, Frangible, HP, etc. ammo you wanted.

Re: [Ultra-Tech] Bioplas Guns?
 

The big problem is that the stuff is flexible. Even rigid types probably aren't super-hard, and are likely to lack wear resistance, so barrel wear will be a major problem (and I'm not convinced self-repair that's suitable for a flexible suit will do for a gun barrel's lining).

Also, it would make the TL11 Cannibal Nanokit largely redundant, and seems generally superior to Memory Metal, etc.

I think that gun barrels and bolt faces, etc. will need to be metals or similarly hard and dense metallic ceramics if they're to last for a few TLs yet. For ones that only need to last a short while hard plastics with ceramic barrel linings (non-metallic if it's to get through scanners) can do, though over-using such a gun might lead to finding out it's reached it's 'use by' when it catastrophically fails.

Re: [Ultra-Tech] Bioplas Guns?
 

Yeah, I'm thinking a metal barrel, bolt, etc will be appropriate. As I mentioned above, I believe an extendable metal barrel is doable when combined with bioplas. To be more clear, I'll try to use some ASCII art. Let's say we have a weapon that has a barrel that can be 10" (pistol), 15" (carbine), 20" (rifle), 25" (long rifle), or 30" (sniper/payload rifle). Left is how it would look from the side without the bioplas (or with clear bioplas), right is how it would from the front without the bioplas (or with clear bioplas).

This would be a weapon that can be concealed, but it would still have the same mass and volume as the full weapon, whereas the cannibal nanokit is a tiny tube of paste weighing in at 1% of the mass of the item. You'll be hard pressed to smuggle a bioplas sniper rifle in an implanted Flesh Pocket (UT211), but a cannibal nanokit that lets you make a sniper rifle in short order would be perfectly doable.

As for memory metal, UT seems to lack stats for that - it's mentioned alongside bioplas on UT90 (where it's indicated to be TL 10+), but UT170-171 goes straight from smart bioplastics (bioplas, TL 9) to living metal (TL 12).

Yeah, this is my inclination, and it avoids the issue of bioplas' low density. There may be some all-bioplas guns in use, probably mostly in the form of single-shot, low recoil weapons - low-velocity grenade launchers, flare guns, etc. Criminals and the like might have all-bioplas "zip guns" or similar as well, only working for a few shots before they need to regenerate.

It also occurs to me that bioplas would be a great material for magazines - no need to worry about the spring wearing out when the magazine itself can function as a self-healing spring.

Re: [Ultra-Tech] Bioplas Guns?
 

They would make great squeezebore weapons, since self repairing means they can offset the disadvantages of real life squeezebores in exchange for higher velocities. As well as progressively accelerating rifling rates, and any other feature that might normally be machined, since these wouldn't need machining if the bioplas simply holds a programmed form.

Re: [Ultra-Tech] Bioplas Guns?
 

To a large degree it comes down to what you want bioplas to be capable of, but bear in mind that TL 10 portal scanners (UT104) can just directly detect explosives.

Re: [Ultra-Tech] Bioplas Guns?
 

The only thing that's listed that's made of memory metal is the Morph Axe, I think. None of the things they turn into have complex parts, so I suspect a 'morph gun' would have some large parts that change shape, and a handful of little bits (spring, firing pin, etc.) that have to be carried separately.

Re: [Ultra-Tech] Bioplas Guns?
 

I've got a program that will let you shoot a couple more shots beyond the built-in-down. Its a life-saver!

Seriously, I do expect you want an override for that, at least in combat situations.