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Old 09-29-2016, 01:16 PM   #246
Tomsdad
 
Join Date: Jan 2010
Location: Brighton
Default Re: Emerging smokepowder weapons in my fantasy

Quote:
Originally Posted by Icelander View Post
D&D 3e did indeed add to a character's score when using a magical item that granted ability bonuses and that's what I did in GURPS. It did not feel fun to utterly devalue the ST score of characters in favour of a magical item, for one thing, because it made the archetype of 'Strong Guy' worthless if someone else found (or could afford to commission) such an item.

Very true


Quote:
Originally Posted by Icelander View Post
I'm trying to find similar weapons, but it's a bit of a struggle. It seems a lot of the stats for potential benchmarks are suspicious.

Why is a 11.2 lbs. 20-gauge blunderbuss firing what appear to be seven 9mm lead shot only ST 7† in LT while the 20-gauge black powder shotgun in HT, weighing in at 10.7 lbs. and firing seven sligthly smaller buckshot, is ST11†?
Well assuming you are talking about the Tower gun in HT, the HT one is lighter and firing significantly more (13x 1d compared to 7x 1d) and it's 11g not 20g.

But yeah In general I take your point

Quote:
Originally Posted by Icelander View Post
For that matter, why is the 17 lbs. Fowling Piece, Double only ST8† in LT?
Yeah I take your point. I suspect it's a factor of how weight, MinST and Rcl interact (obscured by the fact that we don't have a slug Rcl value here)

Quote:
Originally Posted by Icelander View Post
Basing it on weapons of similar weights that have a similar real world recoil impulse is pretty much the only thing I can do, but for that, I've got to figure out what assumptions underlie those weapon stats I use as benchmarks.
Yep

Quote:
Originally Posted by Icelander View Post
I've established that REF 0.8 smokepowder comes in very fast-burning pistol versions as well as slightly slower burning versions for longarms. It has a higher peak pressure than mundane black powder and can accelerate shot to over 3,500 fps, at least when set off by magic that ignites much of it simultaneously within a near-indestructable dragonbone barrel. More normally, it achieves the higher range of black powder velocities easily.
That is fast! (although I get that usual guns won't get that high) But C17th Muskets we're firing at a much slower velocity than that (that's a link straight to a PDF called "Ballistics of 17th Century Muskets " not web page) Sorry reading you post in the Chinese guns threads I realise I'm not telling you anything you don't already know here! But ultimately I think the combinations of such high peak and TL4 metallurgy, is going to mean needing very sturdy sections of barrel where the peak will be contained.


Quote:
Originally Posted by Icelander View Post
The part of a gun's weight which comes from making the barrel strong enough for the charge is often not a major factor. Elephant guns were made heavy to help a relatively normal human handle the recoil, not because only super-heavy barrels could take the charges for 4-bore or 8-bore round balls.
Elephant guns weren't firing that higher pressure peak / energy load (certainly nothing like 3500 fps) even a modern day .700 H&H nitro express is 2000fps

C19th 4g elephant guns were really just big short barrelled shotguns firing a sold ball at low velocity relying on mass to damage the target. Which is why even with that mass 1/2d is low on these guns

Also if your metallurgy isn't great than you have to overcompensate

Quote:
Originally Posted by Icelander View Post
Sure, barrels which last thousands of shots with powerful, high-velocity loads are expensive, but they don't need to be all that heavy. It's generally cheaper to go with a heavy barrel for an extra margin of safety, but while economising on gunsmithing made sense in real history, it makes less sense when the cost of the ammunition is some orders of magnitude higher.
Well again I think your underestimating how much more reliable, consistent metallurgy is a factor*. There's a reason why the 4d+2 (0.80 calibre) musket at TL4 is 20lbs, but the 4d+2 (0.75 calibre, so not significantly smaller) Brown Bess flintlock at TL5 is half the weight.

*especially as weak spots and failure points will fail more consistently when subjected to normal use (i.e. being fired) than a weak spot in say a piece of armour that might go unnoticed for a while, and might even be less obvious and catastrophic when it does fail.

Quote:
Originally Posted by Icelander View Post
It's not just a matter of the weapon being late TL4. It's better as a pistol than all smoothbore muzzleloading TL5 pistols, including being more accurate than the more expensive and TL5 Wogdon Duelling Pistol, specifically noted as being designed for accuracy in a smoothbore, and more accurate as a longarm than any TL5 smoothbore.

As for comparing it to TL4 longarms, it's for some reason +2 Acc relative to full-size military fusils*, +1 Acc relative to all other longarms. Despite weighing in at only 3.9 lbs. with a collapsible stock (heavier than a normal stock at our TL, at least), while the others are full-size weapons, with proper stocks and presumably longer barrels.

*Why, oh, why does Acc for those go down to pistol-levels when they are chambered for a slightly heavier caliber than hunting fusils?
No you are right. The more I think about it, the more I see this as a gentlemen's hunting gun / show off gun. And would assume it's fine accurate and bump up the price. (that fits better with the range and as well)

Last edited by Tomsdad; 09-30-2016 at 05:28 AM.
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