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Guns in life-like cellular automata

Due to the small speed-of-light spaceships in many of the rules with B2, it is somewhat trivial to find low-period guns in these rules. I think it would be infeasible to keep track of all of the B2 rules that contain guns on this page. The 'Guns in Life-like cellular automata' section should probably say something along these lines: "Due to some small spaceships in life-like cellular automata with birth at two cells (B2) many low-period spaceship guns have been found using tools such as WinLifeSearch. In contrast, there are very few rules without B2 that are known to contain guns. The following is a list of rules without B2 that have known guns: ..."
~Sokwe 07:02, 16 October 2010 (UTC)

Seconded. (I created the section initially.) Calcyman 21:12, 17 October 2010 (UTC)

I'm not sure if LWSS (MWSS, HWSS...) guns should be noted in the section "other guns"; they might deserve a separate listing... or a footnote to the glider section, since I presume most of those are based on the 3-glider synthesis. Any rule with small spaceships like the glider is bound to have glider constructions for various objects, so it doesn't seem to me that having glider-compounding guns is a particularly interesting fact about a rule. Gliderless guns are known for Life itself however, as well as for HighLife.

Also, the B37 rules must be something else than LWSS guns; would that be guns firing "Rderships", a slip of the finger, or something else? (Some general sourcing wouldn't hurt, either.) --Tropylium 06:16, 19 September 2011 (CDT)

True-period gun credits

The list of credits for true-period guns is difficult to read. I suggest replacing it with a table, like the one on the oscillator page. It could look something like this:

Period Discoverer Year of discovery
20 Matthias Merzenich and Noam Elkies 2013
22 David Eppstein and Jason Summers 2000
24 Noam Elkies 1997
30 Bill Gosper 1970
36 Jason Summers 2004
40 Adam P. Goucher, Jason Summers, and Matthias Merzenich 2013
44 David Buckingham 1992
45 Matthias Merzenich 2010
46 Bill Gosper 1971
48 Noam Elkies 1997
50 Dean Hickerson and Noam Elkies 1996
54 Dietrich Leithner 1998
55 Stephen Silver 1998
56 Dietrich Leithner 1998
59 Adam P. Goucher and Jason Summers 2009
60 Bill Gosper 1970

Arrangement of guns

I found a P60 glider gun where two Simkin glider guns delete every other glider from a Gosper glider gun.

x = 139, y = 53, rule = B3/S23 25bo$25bobo$8b2o18b2o4b2o63bo$6bo3bo17b2o4b2o61b3o$2o3bo5bo16b2o66bo$ 2o2b2obo3bo8bo4bobo68b2o$5bo5bo9bo3bo$6bo3bo5bo2b3o$8b2o2$100b2o5b2o$ 100b2o5b2o2$28bo74b2o$26bobo74b2o$27b2o69b2o$97bo2bo$100b2o$80b2o13bo 3b2o$80b2o12bo4bo$35bo58b3o$36bo39b2o5b2o$34b3o39b2o5b2o6$43bo$41bobo$ 42b2o2$129bo$127b3o$126bo$50bo75b2o$51bo$49b3o3$130b2o5b2o$130b2o5b2o 2$115bo17b2o$114b2o17b2o$113b2o$114bo2bo$115b2o$110b2o$110b2o2$106b2o 5b2o$106b2o5b2o!

-wwei23 10:17 PM 9/30/2015 NY time

Spaceships with guns

Is there a list of spaceships that are known to have guns? It may be useful to compare to a list of synthesizeable spaceships. That way you can tell what spaceships could be made guns for but do not have guns. Moosey (talk) 01:08, 7 March 2019 (UTC)

There's no single comprehensive list that I know of, but there aren't _too_ many different places to look for spaceship guns -- except for c/2 spaceships mostly made out of *WSSes, and Corderships. There are so many spaceships in those categories that it's hard to find for sure whether a recipe has been made and converted into a gun.
There's a pretty good summary for spaceships with different velocities, in one of the tables on the Game of Life Status page. But that mostly helps for velocities where there's only one or a few known spaceships. Even then, to find the actual guns you might have to hunt around a bit, particularly in these two forum threads. Maybe that status page would be a reasonable place to put a new table for all synthesizable spaceships, with columns for "Gun?" and "Glider-to-spaceship converter?".
I should probably add a few more pointers in the first post of that second thread; sometimes I remember to mention guns, but not always because they're not entirely relevant to stable signals. If you feel like doing any digging for spaceship gun links, maybe post them in that thread and I'll add them to the initial post?
The did you know items about spaceship syntheses were pretty much up-to-date until recently, I think. The synthesizable c/4 spaceship is too new to be a Did-You-Know (and nobody seems to have been tempted to build a gun or a glider-to-46P4H1V0 converter yet). Dvgrn (talk) 19:25, 7 March 2019 (UTC)
Oops, I forgot about the table in Glider synthesis. Looks like you found that without any trouble, though! Dvgrn (talk) 23:36, 8 March 2019 (UTC)