I'm 100% for specific limits on nerf modifications. However, I wouldn't limit them that far.Jay Belarpin wrote:I was just reminded about Nerf guns. Since they can be so heavily modified and improved upon I suggest we say "Must use stock spring."
For one, using 0.59J as a benchmark is a real problem. The surface area of the projectile makes a huge - HUGE - difference here; a .5J impact from a 1mm-square rigid object and a 5J impact from a 10mm-square rigid object are going to be percieved by the target as approximately the same. 0.59J is an absolutely appropriate standard for when you're getting hit with something the size/rigidity of a BB. But because nerf darts have 20 times the impact area of a BB (1mm-sq vs 19.94mm-sq), AND because they squish to absorb impact whereas a BB is a rigid object, using the same safety guidelines for both BBs and nerf darts makes no sense.
The British restrict air rifles heavily, and so they've already done the math.
A 1-gram nerf elite dart moving at 94.710fps crosses the threshold for something "no longer allowed to be a toy." This is an 8J impact.
An air rifle needs to fire a 1.5g slug at 338fps to generate an 8J impact. Comparing it to our 0.2g, 250fps BBs, it would need to be 8 times heavier and 50% faster to get to the point where it becomes dangerous.
What that means is that there's a LOT of room for nerf guns to be improved before they get anywhere NEAR the "danger" levels. The total list of stock Nerf springs is here:
They top out at 4kg. Which means that a 2kg limit (which was put forth last time this conversation happened on Facebook) is probably a bad idea. Looking at spring-replacement sites, it seems that 5kg springs are extremely common and inexpensive, so we should recommend that at a cap.
Do note, though, that there's absolutely no way to police the specific spring weight being used, though. For one, nerf does occasionally mess around with spring weights, and your brand-new Maverick may have a 4kg spring, while my old one may be so worn the spring only gives 2kg. So you can't tell without opening up the nerf gun in the first place. Second, anyone who does any meaningful painting of their nerf guns (more than just hitting it with a can of spray paint) has to take their gun apart anyway. Which means that, if we want nicely modified and painted nerf guns, people are absolutely going to have the opportunity to slip a 4kg spring in for a 3kg spring if they want to.
Last, removing the air restrictor is absolutely something that needs to be legal. It adds about +5fps and, more importantly, it eases the pressure on the spring and O-rings, extending the lifespan of the gun.
In the end, I'd just put a maximum fps cap on nerf guns. Currently, stock nerf dart guns fire between about 35-60fps. I've chrono'd my Vulcan at 37fps, and it's totally unmodified. An unmodified Maverick in my backstock is about 44fps, and I've seen Youtube of unmodified Hammerstrikes in the 55fps region. I'd put a maximum cap on nerf guns in the 75-80fps range, and you can modify them all you want within that. Do note that the nerf ball guns that came out last summer are firing the balls at 100-110fps, so those would need to be dealt with.