{"id":67480,"date":"2016-12-30T16:12:41","date_gmt":"2016-12-30T21:12:41","guid":{"rendered":"https:\/\/www.gunsamerica.com\/blog\/?p=67480"},"modified":"2016-12-30T16:12:41","modified_gmt":"2023-08-20T14:48:53","slug":"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review","status":"publish","type":"post","link":"https:\/\/gunsamerica.com\/digest\/versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\/","title":{"rendered":"One Lower &#8211; AR Mags, AK Mags, 9mm Mags &#8211;  Windham RMCS-4 &#8211; Full Review."},"content":{"rendered":"<p>To learn more, visit <a href=\"https:\/\/www.windhamweaponry.com\/pdf\/NewTechSeets\/RMCS-4.pdf\" campaign=\"WindhamMultiCal\" target=\"_blank\" class=\"clickTracking\">https:\/\/www.windhamweaponry.com\/pdf\/NewTechSeets\/RMCS-4.pdf<\/a>.<\/p>\n<p>To purchase on GunsAmerica.com, click this link: <a href=\"https:\/\/www.gunsamerica.com\/Search.aspx?T=RMCS\" campaign=\"WindhamMultiCalonGA\" target=\"_blank\" class=\"clickTracking\">https:\/\/www.gunsamerica.com\/Search.aspx?T=RMCS<\/a>.<\/p>\n<p>During the late 1980s and early 90s, Bushmaster was the only real alternative to the Colt if you wanted an AR-15 rifle. They were a real company that made stuff, not just a business ordering parts with their name on them. Bushmaster was based in Windham Maine, and for many years they created innovative products for civilian, law enforcement and militaries across the globe. In 2006, Bushmaster was sold to Cerberus Capital Management, which was named after the mythological three-headed dog that guarded the gates of Hades. As part of this deal, they were later packed up from Maine and moved, lock stock and barrel, to New York.<\/p>\n<div id=\"attachment_67501\" style=\"width: 1210px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-1-of-31-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67501\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-full wp-image-67501\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-1-of-31-1.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"1200\" height=\"800\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-1-of-31-1.jpg 1200w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-1-of-31-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-1-of-31-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-1-of-31-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-1-of-31-1-1024x683.jpg 1024w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/a><p id=\"caption-attachment-67501\" class=\"wp-caption-text\">The RMCS-4 comes packed in a custom foam cut Plano case that holds all the parts needed for the four chamberings.<\/p><\/div>\n<p>About the time the company was moved to New York, the previous owner Mr. Richard E. Dyke, had his non-compete agreement expire. Mr. Dyke also owned the land and facilities that were the longtime home of Bushmaster. Something else that Cerberus had left in Mane was the skilled group of people who knew how to build AR-15s.<\/p>\n<p>A few people were engaged and the next thing you knew, the band was getting back together! In three short years, they were shipping rifles again, this time with the credo \u201cThe Quality Goes In, Before The Rifle Goes Out\u201d under the brand Windham Weaponry.<\/p>\n<p>I, for one, am glad to see a quality manufacturer back on the market!<\/p>\n<div id=\"attachment_67499\" style=\"width: 1210px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67499\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-full wp-image-67499\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"1200\" height=\"800\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1.jpg 1200w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1-1024x683.jpg 1024w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/a><p id=\"caption-attachment-67499\" class=\"wp-caption-text\">The complete RMCS-4 kit provides you with a reliable four-caliber AR-pattern system that is ready to go right out of the box.<\/p><\/div>\n<h2>More History<\/h2>\n<p><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Pricing-1.png\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"wp-image-67500 alignright\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Pricing-1-400x93.png\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"430\" height=\"100\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Pricing-1-400x93.png 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Pricing-1-150x35.png 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Pricing-1.png 710w\" sizes=\"(max-width: 430px) 100vw, 430px\" \/><\/a>At the 2016 SHOT Show, Windham Weaponry announced that they would be showing a groundbreaking new rifle that would allow the user to convert between calibers by changing out the barrel, mag well, and bolt carrier group\u2014all while utilizing the same lower and upper receivers. They were going to have three versions available, with up to four caliber options in one AR platform rifle. These caliber options would be .223, .300 BLK, 7.62\u00d739 and 9\u00d719. Windham would swap in a CMMG .22 conversion kit in place of the .300 BLK if desired. Today, we are considering the <a href=\"https:\/\/www.windhamweaponry.com\/pdf\/NewTechSeets\/RMCS-4.pdf\" campaign=\"WindhamMultiCal\" target=\"_blank\" class=\"clickTracking\">RMCS-4<\/a>, with all four (.223, .300 BLK, 7.62x39mm and 9mm) chamberings included in the kit.<\/p>\n<div id=\"attachment_67514\" style=\"width: 331px\" class=\"wp-caption alignright\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-29-of-31-1-e1483129998532.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67514\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-medium wp-image-67514\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-29-of-31-1-e1483129998532-321x300.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"321\" height=\"300\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-29-of-31-1-e1483129998532-321x300.jpg 321w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-29-of-31-1-e1483129998532-150x140.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-29-of-31-1-e1483129998532-768x717.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-29-of-31-1-e1483129998532.jpg 855w\" sizes=\"(max-width: 321px) 100vw, 321px\" \/><\/a><p id=\"caption-attachment-67514\" class=\"wp-caption-text\">The heart of the carbine&#8217;s multi-caliber system is the modular, swappable magwell system.<\/p><\/div>\n<h2>SPECS<\/h2>\n<ul>\n<li><strong>Chambering<\/strong>: .223, 300 BLK, 7.62x39mm and 9mm<\/li>\n<li><strong>Barrel<\/strong>: 16.12 inches<\/li>\n<li><strong>OA Length<\/strong>: 32.5 to 36.25 inches<\/li>\n<li><strong>Weight<\/strong>: 7 pounds<\/li>\n<li><strong>Stock<\/strong>: Collapsible<\/li>\n<li><strong>Sights<\/strong>: None<\/li>\n<li><strong>Action<\/strong>: Direct gas impingement<\/li>\n<li><strong>Finish<\/strong>: Matte black<\/li>\n<li><strong>Capacity<\/strong>: Variable<\/li>\n<li><strong>MSRP:<\/strong> $2,971 (as tested)<\/li>\n<\/ul>\n<h2>Unboxing<\/h2>\n<p>When the discrete cardboard box arrived, I popped it open and out slid a lockable Plano Molding 36\u201d All-Weather Storage Case, with a custom-cut Mil Spec foam interior. Within said storage case was held a bounty of hardware. I glanced around and saw a complete M4 rifle without sights or optic, three magazines, three extra barrels, three total magazine wells, three total bolts and a sling. I was impressed with the package; it looked like a functional layout for field use.<\/p>\n<div id=\"attachment_67503\" style=\"width: 1210px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-5-of-31-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67503\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-full wp-image-67503\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-5-of-31-1.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"1200\" height=\"800\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-5-of-31-1.jpg 1200w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-5-of-31-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-5-of-31-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-5-of-31-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-5-of-31-1-1024x683.jpg 1024w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/a><p id=\"caption-attachment-67503\" class=\"wp-caption-text\">The lower receiver of the RMCS is split into two parts\u2014the forward modular mag well and the rear half with which it interfaces.<\/p><\/div>\n<p>After looking through the manual that was included, I figured out that step one would be to locate the multi-tool that had come with everything else. The multi-tool served as a chamber indicator, punch to push the pins out, and a pin to depress the detent on the trigger guard. This tool would be more than handy for smooth caliber changes.<\/p>\n<p>The next big standout is the barrel change method. The key to barrel interchangeability is on the underside of the MCS Upper Receiver. Once the Barrel Retaining Block is unlatched and moved forward, the Barrel Retaining Arms rotate out to release the barrel and gas tube. The new barrel is inserted and the process is reversed to secure it in place. All the barrels are machined from 4150 Chrome Moly Vanadium Steel, chrome-lined (except the 9mm Barrel, which is Melonite finished) and clearly stamped with caliber for clear selection.<\/p>\n<p>The included multi-tool is used to push the pins holding the upper and lower receiver together. Once the upper and lower receiver are separated, changing the bolt (if necessary; .223 and 300 BLK share the same bolt) is standard AR-15 fare. All the bolts are machined from Carpenter 158 steel with staked gas keys.<\/p>\n<p>[one_half]<\/p>\n<div id=\"attachment_67506\" style=\"width: 410px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-17-of-31-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67506\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-medium wp-image-67506\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-17-of-31-1-400x267.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"400\" height=\"267\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-17-of-31-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-17-of-31-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-17-of-31-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-17-of-31-1-1024x683.jpg 1024w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-17-of-31-1.jpg 1200w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><\/a><p id=\"caption-attachment-67506\" class=\"wp-caption-text\">The .223\/300 bolt carrier has rings behind the lugs to differentiate it from the similar-looking 7.62x39mm bolt carrier group.<\/p><\/div>\n<p>[\/one_half]<\/p>\n<p>[one_half_last]<\/p>\n<div id=\"attachment_67504\" style=\"width: 410px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-6-of-31-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67504\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-medium wp-image-67504\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-6-of-31-1-400x267.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"400\" height=\"267\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-6-of-31-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-6-of-31-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-6-of-31-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-6-of-31-1-1024x683.jpg 1024w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-6-of-31-1.jpg 1200w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><\/a><p id=\"caption-attachment-67504\" class=\"wp-caption-text\">The RMCS-4 comes with three bolt carrier groups: One for the 7.62&#215;39, one for both .223 and 300 BLK, and one for 9mm.<\/p><\/div>\n<p>[\/one_half_last]<\/p>\n<p>Finally, the coolest part of the concept is the modular receiver and magazine well, which are CNC machined from forged 7075 T6 aircraft aluminum. The process of changing the magazine well begins with extending the pin on the orange multi-tool, then depressing the detent holding the trigger guard. The trigger guard is swiveled down; this mechanism is designed to permit a gloved hand to fire the gun. Finally, the magazine release is depressed, and the magazine well slides up and off of the lower receiver.<\/p>\n<p>This process works the same for every caliber change. I found that once I was comfortable with the process, it took some two minutes to go from shooting one caliber to shooting the next.<\/p>\n<div id=\"attachment_67508\" style=\"width: 1210px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-19-of-31-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67508\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-full wp-image-67508\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-19-of-31-1.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"1200\" height=\"800\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-19-of-31-1.jpg 1200w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-19-of-31-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-19-of-31-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-19-of-31-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-19-of-31-1-1024x683.jpg 1024w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/a><p id=\"caption-attachment-67508\" class=\"wp-caption-text\">The low-profile AK mag well is shown here. Note that the standard AR-style push button release is used rather than an AK-style paddle\/lever.<\/p><\/div>\n<p>There are a few details I would caution you about to avoid a disaster. Note that the conversion from .223 to 300 Blackout requires only a barrel change. The bolt and magazine remain the same, which is convenient, but also creates a potential risk. One could end up converting the gun while leaving the original ammunition loaded\u2014this could be a very dangerous situation. I have started painting 300 Blackout magazines or marking them with tape, to avoid grabbing a .223 by mistake. Also, note that there are three bolts used between all four calibers, and as I noted above the .223 and 300 Blackout share the same bolt. The 9mm bolt is easy to distinguish, but the 7.62&#215;39 bolt looks remarkably like the .223 bolt. The .223\/300 Blackout bolt is marked with lines below the lugs, cut around the circumference of the bolt, allowing you to confirm that you have the correct choice. I would have preferred a different coating that would have resulted in a different color, such as nickel boron. This could have added another layer of safety to the kit.<\/p>\n<h2>Specifications<\/h2>\n<p>The first rubric of specification for the RMCS-4 is broken down based on what is common to all iterations of the kit. The next table of specifications is specific to each caliber option.<\/p>\n<p>While prepping for my trip to the range, I tried to consider the person who is looking for one gun that shoots four calibers. This could be for any number of reasons that I will discuss later. The real rub come testing time would be point of impact across calibers. Could this be done accurately, with the optic remaining the same across the barrel, bolt, magazine and magazine well changes? To test this, I selected the Trijicon MRO with the see-through riser mount. This red dot with the riser would allow for back up iron sights to be installed and used without change. I felt sure that I was giving up the detail and accuracy that a magnified optic would afford me. However, I felt it was worth the potential sacrifice given the range of calibers and configurations that needed to be tested to truly cover the platform. I was happy to discover that the rifle still fit into the supplied case after the Trijicon MRO was installed.Rationale and range prep<\/p>\n<p><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Specs-on-kit-1.png\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"aligncenter size-full wp-image-67513\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Specs-on-kit-1.png\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"1316\" height=\"463\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Specs-on-kit-1.png 1316w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Specs-on-kit-1-150x53.png 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Specs-on-kit-1-400x141.png 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Specs-on-kit-1-768x270.png 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Specs-on-kit-1-1024x360.png 1024w\" sizes=\"(max-width: 1316px) 100vw, 1316px\" \/><\/a>I selected three different brands of ammunition to allow for reasonable variances that would be expected in a normal range session. This platform would not be practical if the\u00a0trajectory of projectiles had to be matched.<br \/>\nAfter arriving at the range, I had to wait a bit to get an open bay to shoot in. I had 100 yards to work with, which would be no challenge for 3 of the 4 cartridges I was going to fire. To accommodate the one pistol caliber, I settled on 50 yards. I knew that the 9mm round will easily travel 100 yards, but the drop would be around 7 inches, throwing off the point of aim when comparing to the other rounds.<\/p>\n<h2>Range Time<\/h2>\n<p><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Shooting-Results-2.png\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"alignright wp-image-67512\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/Shooting-Results-2-400x135.png\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"545\" height=\"184\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Shooting-Results-2-400x135.png 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Shooting-Results-2-150x51.png 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Shooting-Results-2.png 594w\" sizes=\"(max-width: 545px) 100vw, 545px\" \/><\/a>First up was the .223; after about 10 rounds to zero in I fired a 3-round group for accuracy. I changed to the 300 Blackout next, as this only required a barrel change. I again fired a three-round group. I followed this protocol until I had data on all four iterations. There was only one notable thing that revealed itself during the range session: the 7.62X39 option had no provision to lock the bolt back on an empty chamber.<\/p>\n<p>The resulting data listed above allowed me to draw a few conclusions. First, you could use one optic for all four rounds without significant changes, albeit a red dot. Second, the most accurate configuration was hands-down the .223 round. The point of impact changes between rounds were noticeable, however, I could run the same optic without adjustments on a man-sized target.<\/p>\n<p>The reliability of the gun was 100 percent, which was noteworthy considering that some guns seem to be challenged just to run one caliber reliably, much less four. The transition between calibers was easily done by utilizing the supplied case, and did not require any special accommodations. The supplied magazines were well-chosen and did not present any performance issues.<\/p>\n<p>The one fault I would offer is that the trigger was a bit stiff, and this rifle particularly could have stood to have a smoother trigger. The trigger and my use of a red dot over a magnified optic both detracted from my shooting, and I am quite sure that I did not close in on the maximum mechanical accuracy of this rifle.<\/p>\n<h2>My Bottom Line?<\/h2>\n<p>The platform works well, both as a rifle and as a system. The RMCS-4 is a truly unique concept, but are these factors enough to justify owning it? I think the answer may be yes, especially when considering some other possible scenarios. If you are going to shoot a match in several divisions, requiring several different calibers, this may be the gun for you. If you live in a state where you can only purchase a limited number of guns within a certain timeframe, this could afford you an option. If space is at a premium, and you have the option of adjusting your optic between caliber changes, this is certainly for you!<\/p>\n<p>[one_half]<\/p>\n<div id=\"attachment_67502\" style=\"width: 410px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-2-of-31-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67502\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-medium wp-image-67502\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-2-of-31-1-400x267.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"400\" height=\"267\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-2-of-31-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-2-of-31-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-2-of-31-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-2-of-31-1-1024x683.jpg 1024w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-2-of-31-1.jpg 1200w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><\/a><p id=\"caption-attachment-67502\" class=\"wp-caption-text\">The RMCS-5 comes with an AK mag from Magpul (left), an AR mag for the .223 and 300 BLK (center), and a 9mm &#8220;stick&#8221; mag (right).<\/p><\/div>\n<p>[\/one_half]<\/p>\n<p>[one_half_last]<\/p>\n<div id=\"attachment_67505\" style=\"width: 410px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-12-of-31-1.jpg\" target=\"_blank\" class=\"clickTracking\" campaign=\"versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-67505\" title=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" class=\"size-medium wp-image-67505\" src=\"https:\/\/www.gunsamerica.com\/blog\/wp-content\/uploads\/2016\/12\/RMCS-12-of-31-1-400x267.jpg\" alt=\"One Lower - AR Mags, AK Mags, 9mm Mags -  Windham RMCS-4 - Full Review.\" width=\"400\" height=\"267\" srcset=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-12-of-31-1-400x267.jpg 400w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-12-of-31-1-150x100.jpg 150w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-12-of-31-1-768x512.jpg 768w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-12-of-31-1-1024x683.jpg 1024w, https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/RMCS-12-of-31-1.jpg 1200w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><\/a><p id=\"caption-attachment-67505\" class=\"wp-caption-text\">The heart of the switch barrel system is the dual barrel retaining arm system located on the bottom of the handguard.<\/p><\/div>\n<p>[\/one_half_last]<\/p>\n<p>Plus, if you want to be able to tell your wife that you only own one AR-15, while also having four options, this gun will allow you to do that! The price offers some economy of scale; if you compare the quality of components and consider that you\u2019ll only need one optic rather than four high-quality optics, you start to see some real value. Or, you could just get it because it is cool!<\/p>\n<p>To learn more, visit <a href=\"https:\/\/www.windhamweaponry.com\/pdf\/NewTechSeets\/RMCS-4.pdf\" campaign=\"WindhamMultiCal\" target=\"_blank\" class=\"clickTracking\">https:\/\/www.windhamweaponry.com\/pdf\/NewTechSeets\/RMCS-4.pdf<\/a>.<\/p>\n<p>To purchase on GunsAmerica.com, click this link: <a href=\"https:\/\/www.gunsamerica.com\/Search.aspx?T=RMCS\" campaign=\"WindhamMultiCalonGA\" target=\"_blank\" class=\"clickTracking\">https:\/\/www.gunsamerica.com\/Search.aspx?T=RMCS<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>At the 2016 SHOT Show, Windham Weaponry announced that they would be showing a groundbreaking new rifle that would allow the user to convert between calibers by changing out the barrel, mag well, and bolt carrier group\u2014all while utilizing the same lower and upper receivers. They were going to have three versions available, with up to four caliber options in one AR platform rifle.<\/p>\n","protected":false},"author":40,"featured_media":67499,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_specdata_upc":"","_specdata_placement":"","footnotes":""},"categories":[872,7,694,324,37],"tags":[702,714,787,187,613,132,102,108,620,803],"featured":[],"hunt365":[],"class_list":{"0":"post-67480","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-gun-reviews-ar-15","8":"category-gunsamerica-authors","9":"category-gun-reviews","10":"category-jon-hodoway","11":"category-gun-reviews-rifles","12":"tag-223-rem","13":"tag-300-blk","14":"tag-7-62x39mm","15":"tag-9mm","16":"tag-ar-15","17":"tag-buzz","18":"tag-feature-articles","19":"tag-guns","20":"tag-tactical","21":"tag-windham-weaponry"},"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.3 (Yoast SEO v27.3) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>One Lower - AR Mags, AK Mags, 9mm Mags - Windham RMCS-4 - Full Review.<\/title>\n<meta name=\"description\" content=\"One Lower - AR Mags, AK Mags, 9mm Mags - Windham RMCS-4 - Full Review. - Authors\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/gunsamerica.com\/digest\/versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"One Lower - AR Mags, AK Mags, 9mm Mags - Windham RMCS-4 - Full Review.\" \/>\n<meta property=\"og:description\" content=\"At the 2016 SHOT Show, Windham Weaponry announced that they would be showing a groundbreaking new rifle that would allow the user to convert between calibers by changing out the barrel, mag well, and bolt carrier group\u2014all while utilizing the same lower and upper receivers. They were going to have three versions available, with up to four caliber options in one AR platform rifle.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/gunsamerica.com\/digest\/versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\/\" \/>\n<meta property=\"og:site_name\" content=\"Gun Reviews and News | GunsAmerica.com\/Digest\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/gunsamerica\" \/>\n<meta property=\"article:published_time\" content=\"2016-12-30T21:12:41+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2023-08-20T14:48:53+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/gunsamerica.com\/digest\/wp-content\/uploads\/2016\/12\/Hero-Shot-2-1.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"800\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Jon Hodoway\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@gunsamerica\" \/>\n<meta name=\"twitter:site\" content=\"@gunsamerica\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Jon Hodoway\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"11 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/gunsamerica.com\\\/digest\\\/versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/gunsamerica.com\\\/digest\\\/versatile-ar-ever-multi-cal-windham-rmcs-4-full-review\\\/\"},\"author\":{\"name\":\"Jon Hodoway\",\"@id\":\"https:\\\/\\\/gunsamerica.com\\\/digest\\\/#\\\/schema\\\/person\\\/62be733e54b3b2ed1aabd8f3f212eb68\"},\"headline\":\"One Lower &#8211; 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