I own the creative rights of the variant rules provided within. Feel free to use them, but do not take credit for them, as they are my intellectual property. Paizo owns the copyright and creative rights of the core rules my variant rules are based off of. These alternate rules are only minor tweaks to incorporate ‘guns’ and gunslingers into campaigns that do not contain black powder, but they are my minor tweaks.
For players and storytellers who like the idea of guns and gunslingers but not the complications and whatnot of introducing black powder to their campaign worlds.
In case anyone else has already come up with other alternate rules to incorporate ‘guns’ into their campaign that does not include black powder, feel free to post a link. Any similarities between my alternate rules below and others’ alternate ‘gun’ rules are purely coincidental. As can be seen, my alternate rules are easy to envision (and thus might already have existing similar rules posted on the message boards). I assure you I did not copy any one’s idea (aside using the Pathfinder rules as written as my ‘chalk board’.
First off, the ‘guns’ have the following game statistics.
You will be able to see that I use the crossbows as my basics.
I changed the increased threat range to a higher critical multiplier. It is not easier to score a critical hit, but when you do you do more damage than a standard weapon does. Imagine a baseball player hits the baseball and line drives it right into the pitcher’s face, groin, etc. It is hard to hit the ball with such precision, but when you do hit such ‘soft spots’ it really lays the target low.
The damage type is changed from piercing to bludgeoning for obviously reasons. As these guns are ‘gear works’ contraptions that use a mechanism not unlike a real life air-powered bb gun.
The range is reduced to a third the range of the crossbows as bullets are not nearly as aerodynamic as bolts (and arrows) are.
Hand Gun; 100 gp; Damage 1d4 (1d3 Small); Critical x3; Range 10 feet (5 range increments); Weight 2 lbs. ; Damage Type: Bludgeoning
Heavy Gun; 50 gp; Damage 1d10 (1d8 Small); Critical x3; Range 40 feet (5 range increments); Weight 8 lbs. ;Damage Type: Bludgeoning
Light Gun; 35 gp; Damage 1d8 (1d6 Small); Critical x3; Range 20 feet (5 range increments); Weight 4 lbs. ; Damage Type: Bludgeoning
Repeating Heavy Gun; 400 gp; Damage 1d10 (1d8 Small); Critical x3; Range 40 feet (5 range increments); Weight 12 lbs. ; Damage Type: Bludgeoning
Repeating Light Gun; 250 gp; Damage 1d8 (1d6 Small); Critical x3; Range 20 feet (5 range increments); Weight 6 lbs. ; Damage Type: Bludgeoning
Loading a gun requires two hands to load and loading a gun provokes an attack of opportunity.
Reloading a hand gun or a light gun is a move action.
Reloading a heavy gun is a full-round action.
Reloading a repeating gun (whether light or heavy) with a bullet clip is a full-round action.
You can shoot a hand gun with one hand without penalty. You can shoot a hand gun with each hand, and take a penalty on attack rolls as if attacking with two light weapons.
You can shoot a light gun or a repeating light gun with one hand with a -2 penalty on attack rolls. You can shoot a light gun or repeating light gun with each hand, and take a penalty on attack rolls as if attacking with two light weapons, and these penalties are cumulative with the attack penalty for shooting a light gun or repeating light gun with one hand.
You can shoot a heavy gun or a repeating heavy gun with one hand with a -4 penalty on the attack rolls. You can shoot a heavy gun or heavy repeating gun with each hand, and take a penalty on attack rolls as if attacking with two one-handed weapons, and these penalties are cumulative with the attack penalty for shooting a heavy gun or repeating heavy gun with one hand.
Misfires: These guns have misfire value of 1. On a misfire the misfire value goes up by 4 and the gun gains the broken condition. If the gun already has the broken condition when it misfires, it instead gains the jammed condition. It requires the same amount of time and action to reduce a jammed condition to a broken condition as it does to remove the broken condition. A jammed gun cannot be used to shoot at all.
Unlike black-powder guns, these guns only do bludgeoning damage and do not target touch AC.
Rapid Reload feat: When taken for one of the following guns it reduces the reload time as follows:
Hand gun or light gun becomes a free action.
Heavy gun or a repeating gun (regardless if it is heavy or light) becomes a move action.
The Gunslinger
The gunslinger only requires a few changes, the most important ones being deeds that work due to black powder-powered bullets.
Make the following changes to the Gunslinger to create gunslingers that exist in campaigns in which black powder does not exist.
Weapon and Armor Proficiency: Gunslingers are proficient with simple weapons, light and one-handed martial weapons, the hand gun, the light gun, the heavy gun, the repeating light gun and the repeating heavy gun. Gunslingers are proficient with light armor and the armored coat.
Gunsmith: A gunslinger begins play with a battered gun, which cannot be repeating heavy gun or a repeating light gun.
Gunsmithing feat: This feat is changed in the following ways:
Crafting Guns: You can craft a gun in one day, as each of the five guns has a value of less than 1000 gp.
Crafting Ammunition: You can craft regular (non-special material) bullets for 1/10th the market price. You can craft bullet clips (including the five bullets) for half the market value. Bullet clips are what repeating guns use as ammunition.
Gun Training: At 5th level, a gunslinger chooses a specific gun (hand, light, heavy, repeating light or repeating heavy). The gunslinger gains a +1 to attack and damage rolls when attacking with that kind of gun. At 9th, 13th and 17th levels, a gunslinger chooses another type of gun and gains a +1 to attack and damage rolls when attacking with that kind of gun. The bonuses from guns he chose at earlier levels increase by an additional +1 at each of these levels as well. At 13th level, a gunslinger never misfires with the gun he chose at 5th level. At 17th level, a gunslinger never misfires with the gun he chose at 9th level.
Deeds
Level 1 Deeds
Gunslinger’s Dodge
Quick Clear
Up Close and Deadly: As the Pistolero deed, but it only applies when attacking with hand guns. A gunslinger whose Gun Training attack bonus effectively negates the attack penalty for shooting a specific gun one-handed can also use Up Close and Deadly when he uses the gun one-handed.
For example a gunslinger who chooses the light gun as his first Gun Training weapon would be able to use Up Close and Deadly while using a light gun (but not a repeating light gun) one-handed when he reaches 9th level (as the +2 Gun Training bonus effectively negatives the -2 attack penalty for firing a light gun with one hand).
Another example would be a gunslinger who chose repeating heavy gun at 5th level would be able to use Up Close and Deadly when he reaches 17th level, but would not be able to use Up Close and Deadly with a non-repeating heavy gun.
Level 3 Deeds
Gunslinger’s Initiative
Pistol Whip: Hand guns do 1d3 damage, light guns do 1d6 damage and heavy guns do 1d8 damage. This deed only costs a grit point if you decide to make a combat maneuver check as a free action to knock the target prone.
Fast Guns: As the Musket Master Fast Musket deed, which allows the gunslinger to reload any gun as a move action as long as he has at least one grit point.
Level 7 Deeds
Deadshot
Startling Shot
Targeting
Level 11 Deeds
Bleeding Wound (though not powered by black powder, the body part hit and the angle it is hit could cause bleed damage, which could be external or internal).
Lightning Reload: The gunslinger can now reload any gun as a swift action as long as he has 1 grit point. If the Gunslinger has Rapid Reload with the heavy gun or a repeating gun he can reload that gun as a free action as long as he has 1 grit point.
Twin Shot Knockdown: As the Pistolero deed.
Level 15 Deeds
Evasive
Slinger’s Luck
Gunslinger’s Resilience: As the Gun Tank’s Gun Tank’s Resilience
Level 19 Deeds
Cheat Death
Death’s Shot
Stunning Shot
I don't see anything unique enough or different enough from the normal rules, or from any other past guns rules here for you to be able to claim ownership of this. You can't claim variant rules to OGC as your own, anyway, since any mechanic derived from or coming from the SRD is considered OGC.
If you named your light gun a "D-Masterpistol," you could conceivably claim credit for it and take out a copyright, so long as it was included in the text of an entire work (you have to write a story or entire ruleset, as you cannot simply copyright a single name by itself). But you didn't do that here, and "hand gun" is not something you can really make a trademark out of, or claim as your own intellectual property.
Likewise, you surely cannot claim the names of feats and abilities from Pathfinder as your own, especially so unchanged as these are.
Here's my advice: Write up a campaign setting, name your guns something flashy, include a backstory on what propels the ammunition, then give the whole work a name, give the OGL its due, and copyright the fluff text as your own creation.
Thank you for the advice, Bruunwald.
I am working on a setting and very detailed unique rules set. I will be giving the OGL its due when I am ready to publish it.
I was referring to others not being allowed to claim my alternate rules as their own creative process/property (as in attempting to claim they were the one that thought of my specific rules tweaks that allows 'guns' and gunslingers in games/campaigns that black powder is non-existent in).
I was in no way attempting to imply that I own the creative rights of the material that I based my alternate rules on, which I did point out in my initial post above.
I have some experience in creating alternate rules set of existing rules set, that have been promoted by the co-creator of the original rules that I did a major alternate rules set for, which players around the world enjoyed, and some enjoyed my rules set more than the core rules set.