Author Archives: btrettel

boltsniper’s optimal barrel length formula

Whenever there is a thread about one of the holy grails of Nerf ballistics, an equation for the barrel length that maximizes performance, someone is bound to mention the results of some tests boltsniper did in 2005 when he was designing the FAR. boltsniper, for the uninitiated, is one of the few engineers in the […]

Solving the point mass model of a dart’s trajectory, part one

This blog post is relatively math heavy and it serves mostly as notes for my own use. I will assume some familiarity with differential calculus and ordinary differential equations. I also will assume some familiarity with the basic equations that govern the motion of Nerf darts after they leave the barrel. Yesterday I had an […]

Approximate expansion diameter of latex tubing

I previously wrote about how to estimate the expansion diameter of latex tubing, but I made no measurements to verify that the formula I suggested, where is the unexpanded inner diameter of the tube and is the unexpanded tube wall thickness, was accurate. Back in 2010, I made some measurements for tests that were aborted […]

Next two months

Sorry all, but I’ll be basically inaccessible for the next two months. At the moment I’m working at NIST with Randy McDermott and I’m staying at a hotel with terrible internet. I’ll see what I can do on weekends.

My challenge to Nerf rifling believers

Do you believe most Nerf darts can be made more stable by spinning? If so, this challenge is for you! The challenge is simple: Provide objective and statistically significant evidence that spinning darts improves stability, precision, or range. Some notes Rifling barrels for Nerf has already been thoroughly debunked. To say it in brief, the […]

Nerf Engineering forum

The Nerf Engineering forum is now open. I’m receptive to suggestions, so let me know at the forum if you have any ideas, especially with regard to its organization.

Temporary NerfHaven archive

I have made a temporary NerfHaven archive for those who wish to browse threads while NH is down. Also, would anyone be interested in a small forum for this blog? I am thinking I’d like to discuss some topics not typically covered at Nerf forums, like, for example, “concept” threads (where the merits of a […]

NerfHaven hack 2011

There has been much speculation about what precisely is going on at NerfHaven recently. The problems at NH are not an April Fools’ joke. The forum software NH uses is vulnerable to SQL injection attacks, and based on the available evidence, it seems that a hacker decided to gets some kicks by screwing with NH. […]

Electro-Pneumatic Revolver by PVC Arsenal 17 build log

Check out this interesting project by PVC Arsenal 17. For those who were wondering, I’m still alive, but I am kept extremely busy with school work. Two grad. classes (one mech. eng., the other applied math), two advanced undergrad. classes (one math, the other mech. eng.), and the senior design course will keep you busy! […]

FANG1 problems and solutions

Back in summer 2010 I decided that I should return to the “projectile-pusher” approach I used in FANG1. I gave up on this approach far too easily. FANG1 worked, but was unreliable. When I started planning FANG2 I considered the unreliability to be inherent to the projectile-pusher design and that nothing could be done about […]