Google recently changed its API usage policy, effectively putting the
non-profit Gmap4 out of business. That’s unfortunate, as Gmap4 was
designed to benefit disaster-management organizations and was doing a great
deal of good in that realm. Since GridScout™ used Gmap4 for its
aerial views, that feature currently won’t work. While this does not affect
GridScout’s primary goal of searching Google Maps and performing bulk
collection of MGRS location data, it does make it harder to verify the
relevance of unfamiliar search results. The maker of Gmap4 has made appeals to
Google in hopes of coming to an agreement, but Google refused. In order to
continue using the Google Maps API in his volunteer efforts, he’d have to shell
out $46,000 per year. So Gmap4 is now gone. Bummer.
I am now considering alternatives to Gmap4, so that I can restore GridScout’s
The ultimate purpose of the GridScout™ map-search tool is to
provide for a better community defense. For that same purpose, I’m building a
new firearm. I call it the RC1. Why RC1? Because it’s easier to explain that
RC1 stands for Reeder Carbine #1 than to explain that PK6 (my original name for
the RC1 concept) stands for Piŝta Karabeno je 6,5 Grendel.
My intent is to create a weapon that is easy to operate in close quarters, very
well suited for up to 300 yards, and still practical up to 500 yards. While
many PDWs are especially good at close quarters and a typical modern carbine is
pretty good up to 300 yards, it seems to me that both are severely handicapped
beyond that range by their low bullet energy and high aerodynamic drag.
I think I can more fully achieve my chosen goals by creating a custom carbine
than by selecting any of the off-the-shelf offerings that I’ve already
considered. So I’m going for it, and upon completion we’ll see how it does.
The RC1 will be based largely on the Alexander 6.5 Grendel Incursion, which is
relatively light and fires the most effective general-purpose cartridge yet
devised for AR15-format firearms. Thanks to the versatility and popularity of
Eugene Stoner’s modular design —the Armalite AR-15 upon which the Grendel
Incursion and many other modern weapons are based—, we now have a standardized
means of interchanging parts to fit the needs of the shooter. The RC1 will take
advantage of this in two important ways.
The bolt will be cycled by a gas piston, based on the Armalite AR-180 design,
which has proven substantially more reliable than direct gas impingement.
Other part selections, inspired by PDWs and by ultralight carbines derived
from the Colt AR15A3, will serve to make the RC1 lighter, more comfortable,
and more maneuverable.
The barrel of the RC1 will be just long enough to avoid the red tape associated
with a short-barreled rifle. This length also serves to keep the muzzle
velocity and bullet energy high enough for practical medium-range use. If I put
a muzzle brake on the barrel, it’ll be a short, single-chamber model to
minimize the added weight and length.
The RC1 will have a very short, fixed-length buttstock. This would make it
uncomfortable with the standard 33° grip angle, so its pistol grip will instead
be nearly vertical, as is common in a PDW. This will place the wrist of the
shooter’s dominant hand in a neutral position, while the short length of pull
will put the entire mass of the RC1 closer to the shooter’s body where it is
more easily supported. This gun will be as lightweight as practical, in order
to further limit muscle fatigue, as even minor fatigue can affect the
steadiness with which the shooter holds his sights on target.
The RC1 will be equipped with two sighting systems:
- A lightweight fixed-power riflescope, sufficient for 500-yard engagements
- Offset iron sights, optimized for quick target acquisition within 50 yards
Progress on this project is as follows. Initially, a few paper parts stand in
for some of the actual parts that I have not yet acquired. With a scope and a
full magazine, I anticipate a total weight of about 6.8 pounds, and a total
length of about 32 inches.
2018-07-05 — Initial concept
2018-07-27 — Weaver K6 scope (paper model)
2018-07-31 — Incognito Arms buttstock
2018-08-02 — Ergo Swift Grip (paper model)
When the RC1 is complete, I will assess the performance of this weapon in a
future post. I’ll provide a link here to make it easy on you.