Talk:M231 Firing Port Weapon

200rpm claim
The article claims that some versions fire at 200rpm, which is much slower than any other small caliber fully automatic weapon than I'm aware of. A typical full auto AR-15 will cycle at 700+rpm. I don't see anything in the sources (which are limited at best) about it, where is that information from?

After thinking about it, it's possible that the cyclic rate was lowered by 200rpm, from the 1050 quoted earlier to 850. Totensiebush (talk) 00:35, 23 September 2014 (UTC)

That really has to be what it means, because I'm having a really difficult time picturing how you would actually achieve making an AR15 shoot at 200rpm in full-auto, without the use of some kind of electronically controlled rate reduction mechanism. More realistically, altering the recoil buffer (buffer weight, spring tension), or outright adding a mechanical rate reduction mechanism, reducing the rate of fire BY 200rpm FROM 1050rpm seems far more likely and plausible.77.110.1.75 (talk) 07:02, 27 March 2019 (UTC)

Service History
As the US forces have fought a number of wars since the Bradley entered service, is there any infomation about service use ? Jim Sweeney (talk) 07:18, 7 May 2008 (UTC)
 * I personnally have not seen any. While I believe the weapon is still issue, the restriction of usable ports and its debatable utility when detached from the vehicle have no doubt restricted its use even in time of conflict.  Of course this is all speculation in of itself, but the only descriptions of its service use that I have heard or read have been purely anecdotal.  It would be helpful if a manual or supplement mentioning it could be found in which one might get a better sense of its intended employment. -- Thatguy96 (talk) 19:53, 7 May 2008 (UTC)
 * If you look at the Stars and Stripes file photo of Ross McGinnis, you can clearly see a m231 FPW in the foreground. It is either used as a close defense weapon for the gunner, or for marking and warning shots in lew of the machine gun.  My money is on close defense.

anyone noticed thai it can be converted to a m4?
the m4 has a collapsable and removable sights and stock, i was wondering, if they were attached to this, wouldn't it become a m4? user:Btzkillerv (User talk:btzkillerv) 17:51, 11 October 2008 (UTC)


 * No, there are still other features it would lack, and the internal functions are a bit different from those of the M4.--LWF (talk) 17:57, 11 October 2008 (UTC)


 * but with some blacksmithing, surely it can be converted into an m4? Btzkillerv (talk) 20:12, 11 October 2008 (UTC)


 * Blacksmithing? No blacksmithing is involved with firearms. In addition, the internal mechanisms are different in more than one way, the gas system is obviously designed differently as the gas port is obviously located closer to the bolt, and the furniture is different, as the M231 lacks a stock, and the forward handguard is completely different, the barrel is of different length, and the profile of the barrel is different as the M231 lacks the barrel cutout for the M203, and appears to be thinner all around. Take a close look at the article and you'll see the M231 has only a 65% parts commonality and that is likely including internal and external parts. So in conclusion, no, the M231 could not be converted to be an M4, they are similar because they are based on the M16, but there are too many differences to allow for a conversion.--LWF (talk) 22:35, 11 October 2008 (UTC)
 * awww Btzkillerv (talk) 20:35, 12 October 2008 (UTC)

"65% parts commonality with M16" claim
What is the source for the claim that the M231 shares 65% of its parts with the M16 rifle?

A quick look at the Technical Manuals (the -23&Ps for armorers and higher levels of maintanance) for the two shows little commonality of parts. The bolt, pistol grip, magazine catch assembly and a few other parts are the same, true. But the bolt carrier, the recoil spring and buffer parts, the fire-control parts and just about everything else are different. Similar, in some cases, but not interchangeable. Even the lower receiver, which is identical in M16s and M4s except for minor cosmetic differences, is different in the M231.

TM 9-1005-309-23&P TM 9-1005-319-23&P — Preceding unsigned comment added by 63.152.103.84 (talk) 11:13, 18 September 2013 (UTC)


 * The M231 lower receiver has a different NSN and PN than the various M16 and M4 lowers, true. But they all have unique NSNs and PNs as well, the only physical difference being the designation stamped on the lower.  Thus the M16A1s (and even XM16E1s) converted to M16A2, various M16 versions converted to M4s, M4s to M4A1s, etc.
 * There is at least one error in the -23&P for the M231. It shows 4 holes (5 even, in some drawings) for pins in the lower: the usual 3 of the M16/M4 series (hammer, trigger/disconnector and auto-sear), and an additional hole for the open-bolt sear of the M231. Actual M231s have only 3 holes (trigger, open bolt sear and auto-sear) but they are all the same diameter, that of the hammer and trigger pins on the M16/M4 series.  I suspect the TM drawings were made with a test or very early production M231 as the model, and that Colt had been simply adding holes to existing M16 lower receivers.  Later M231s (including at least 2 civilian-transferable examples) do not have any extra holes.
 * It would be possible to convert an M231 to an M16/M4 series weapon, but it would require some modifications to the lower receiver. The hole for the hammer pin would need to be drilled (simple enough matter with one of the jigs for making 80% AR lowers) and the internal parts replaced with M16/M4 parts, and if full-auto or burst fire was desired it would be necessary to modify the auto sear to take the larger pin or a bushing of some sort would need to be fabricated to allow the use of the smaller diameter auto-sear pin.  Such bushings have been made for hammer and trigger pins to repair very expensive civilian-transferable M16 lowers, so a similar solution for an M231 lower should be possible.
 * The entire upper half of an M16 or M4 could simply be dropped on the lower at this point. Production M231 upper receivers appear to simply be incompletely machined M16 upper receivers, they even have the markings for the M16/M16A1 rear sight forged in place.
 * Of course the value of a transferable M231 is far too high to make any of this a worthwhile endeavour. 96.241.79.130 (talk) 01:28, 25 February 2023 (UTC)

Competing weapons
In the History section, the bit about "a WW2-era Firing Port Weapon created by Heckler & Koch based on the HK33" makes no sense, as the HK33 was first designed several decades after World War II. Did some text get dropped in the middle? - CarlRJ (talk) 23:18, 19 January 2016 (UTC)


 * It's this edit here. User:Hisredrighthand messed up. Originally it read something along the lines of "[the choices included] the M3, (plus) a FPW created by Heckler & Koch, and [further choices]". The user mangled this into the current formulation; bearing in mind the edit summary he didn't know anything about the topic. The words of Kurt von Hammerstein-Equord are apt; "one must beware of anyone who is stupid and diligent - he must not be entrusted with any responsibility because he will always cause only mischief". -Ashley Pomeroy (talk) 19:10, 16 March 2016 (UTC)