Gun YouTubers are in crisis as the platform tightens restrictions on their controversial content, machine gun videos, and firearms marketing. The strict rules have some in the community, including four very popular channels, leaving YouTube for its less regulated competitors.

While the largest “GunTube” accounts have yet to leave the platform, they have publicly voiced concerns that their content is no longer embraced by YouTube. Many of these channels have millions of subscribers, major brand deals, and established relationships with the platform.

YouTube has long regulated gun videos and firearms on the video site. “How-to” videos on making guns and ammunition and the direct sale of guns is strictly prohibited. In June, the platform, which is owned by Google, rolled out additional restrictions, banning content that depicts the removal of gun safety devices, limiting what viewers can watch videos showing automatic or homemake weapons being discharged to those 18 and up, and removing advertising opportunities from those videos.

The video site also announced it would ramp up enforcement of their 2018 ban on videos posted with the intent to sell firearms or with links to websites selling guns, this includes links to gun retailers and landing pages.

Despite the platform’s history of gun content restrictions, YouTube is home to a plethora of gun-themed channels with more than one million subscribers, not including the myriad of smaller accounts.

“The entire industry feeds off of YouTube, whether they will admit it or not,” said Jon Patton, a YouTube gun reviewer with 369,000 subscribers, on the firearms podcast “The Reload.”

Gun reviews are only part of the “GunTube” community which also includes creators who use the site to display their personal collections or perform stunts using guns.

These channels turn a profit through sponsorship deals from companies making make guns or firearm accessory. According to Bloomberg News, successful “GunTubers” can earn hundreds of thousands of dollars annually in ad revenue and sponsorships. The platform’s tighter restrictions directly impact this process.

With their revenue stream being weakened, several popular gun accounts have moved their operations to Rumble, a video app with notoriously lax rules. The alternative site has become popular among those banned from mainstream social media platforms, including white nationalist Nick Fuentes.

While YouTube has not said why it’s leaning into stricter rules, the site has endured years of backlash for promoting gun culture from advocacy groups and government officials like Manhattan District Attorney Alvin Bragg. A spokesperson for the platform told NBC News, however, that the decision is not in response to a “specific moment or change in law.”