RIP round Ammo [High Tech]: "hollow point" w/ no DR multiplier?

[LokRobster]

I ran a few searches on the forums to see if I could find a discussion on this ammo design, but didn't see any. Please post a link to another thread if it already exists!

In the age-old tradition of building specialty, over-hyped ammunition, a new copper-based expanding bullet has been introduced this year, the RIP round.

After oogling over this stuff for the past few months and never finding it available, a good friend of mine just obtained 5 boxes (100 rounds) and is eager to start shooting with it. Of course this made me want to look into GURPS stats for it...


If the manufacturer's testing and claims are accurate, it seems to combine the penetration attributes of an armor-piercing round with the wounding quality of a hollow point. The 'advantages' may fall inside the granularity of GURPS piercing damage and not really make a noticeable difference.

I am figuring on allowing these in my modern/IW games by giving the advantage of the 1.5x damage for an expanding round, while avoiding the 2x DR multiplier normally inherent to these types of ammo. The main downside to the RIP round is cost and availability.

Does this sound reasonable? What other problems might you assign to (or look for in) this ammunition? Other thoughts?

[Varyon]

So what we have is a flat round that basically has a bunch of needles in the front. The flat round is going to have rather poor penetration and probably not a lot of expansion (it's copper, not lead) - normal damage and AD (0.5). The copper needles are probably going to have normal penetration but are pi- at best - really, they'd probably need a smaller pi category. Assuming around half the mass is the base bullet and half the mass is the needles, an offhand estimate for the round would be that it has half its damage in FMJ, half its damage in HP, with the two combining (1 from FMJ, then 2 from HP, then 1 from FMJ, and so forth). So a 2d+2 9mm pistol would be 1d+1 pi + 1d+1(0.5) pi+. Up against, say, DR 5, that would be 1 from FMJ (DR 4 remain), then 2 from HP (DR 3), then 1 from FMJ (DR 2), then 2 from HP (DR 1), then 1 from FMJ (DR 0), with the remainder getting through to cause injury.

[vierasmarius]

Originally Posted by Varyon

So a 2d+2 9mm pistol would be 1d+1 pi + 1d+1(0.5) pi+. Up against, say, DR 5, that would be 1 from FMJ (DR 4 remain), then 2 from HP (DR 3), then 1 from FMJ (DR 2), then 2 from HP (DR 1), then 1 from FMJ (DR 0), with the remainder getting through to cause injury.

That method seems way too complicated. What you're looking at is effectively a round with the same base damage, but a (0.66) Armor Divisor and a x1.25 Wound Modifier. You could approximate this by making it normal piercing damage with a (0.5) AD, but a x1.3 increase in base damage (or roughly +1 per die).

[DouglasCole]

I did an article on this at gaming ballistic.

http://gamingballistic.blogspot.com/...marketing.html

[Varyon]

Originally Posted by vierasmarius

That method seems way too complicated. What you're looking at is effectively a round with the same base damage, but a (0.66) Armor Divisor and a x1.25 Wound Modifier. You could approximate this by making it normal piercing damage with a (0.5) AD, but a x1.3 increase in base damage (or roughly +1 per die).

I could get behind that. Now, against unarmored flesh it may be about as good as HP, in which case my setup would be 1d+1 pi and 1d+1(0.5) pi++, which approximates to 2d+2(0.7) pi+, or HP with a slightly better Armor Divisor.


EDIT: ...or just use Doug's suggestions, he's a lot more knowledgeable about terminal ballistics (and how to approximate them in GURPS) than I am.

[vierasmarius]

Originally Posted by Varyon

EDIT: ...or just use Doug's suggestions, he's a lot more knowledgeable about terminal ballistics (and how to approximate them in GURPS) than I am.

Yeah, I was only commenting on the rules-mechanical implementation of a "half Hollowpoint" round, not on its real-world viability. =P

[Anthony]

3e had a sort of half hollowpoint round (penetrating core wrapped in a soft shell) that was something like 'treat as either hollowpoint or AP, whichever is better'; I think it was higher tech level and more expensive (make it the same price and TL as APEP, perhaps).

[Dwarf99]

I'd do the 1d+1(0.5) pi++ as base damage with 1d+1 pi as a followup.

[malloyd]

Supersonic aerodynamics can admittedly be pretty surprising, but that thing looks like it would have tremendous drag and stability problems.

And maybe that is the additional wounding mechanism - lack of stablity causing tumbling in the target. It's certainly not the points, or the multiple "wounding channels" in the advertising.

[phayman53]

I found this video which does a pretty thoroug job of showing that the fragmenting parts of these rounds have no more penetration power than a bb or bird shot loaded pistol rounds. The only part of a R.I.P. round likely to hit vitals is the under size and weight copper base. The video is long, but it is worth watching and the guy in it seems to know what he is talking about.