Blanks in my ar. Crazy!

[Drew P]

Okay I have a kooky idea. Some may not think this is safe, and I’m willing to listen to any concerns. I have an old 300bo barrel that I don’t have use for so I was thinking about making it into a blank firing setup, and then brewing up my own blanks. Basically I could do this with a flash hider too, the concept as I understand it is that the adapters plug the barrel to allow gas pressure to build high enough to cycle the bolt. I saw one adapter where they claimed the obstruction was even made as a weak link and in the case of accidental live round firing it would push the obstruction out. I’m not super concerned with that and I can paint this red or something anyway. But what powder and how much could be used for something like this? I’d want a little hole in front if for no other reason than to look like gasses coming out the front for realism. Also, how to hold powder in cases? Must they be crimped or is there another method? I’d guess that shotgun or pistol powder would be the choice but how much? Is there some sort of standard charge for blanks?

[Drew P]

Oh also, I’d want to make these from 223 cases and fire them through the 300bo barrel, I can’t think of a reason this won’t be okay.

[tomme boy]

I thought there was a guy here that was a special effects guy that did all the guns for the movies. He had posted a bunch about how they make blanks in different guns and how to make them run.

At least I think it was on this forum. Might have been Snipers Hide if not on this forum.

[Mal Paso]

The blank guns I've seen are regular ammo firing guns.

There is blank powder, very fast and special blank crimp dies that close the case mouth with a 5 sided crimp.

[WRideout]

When I lived in CA, and was in the Army National Guard, any time we were issued blanks, they came with a blank adapter, which was basically a large orange-painted steel stamping that slipped over the muzzle of an M16, and had a threaded pin to screw into the bore to raise gas pressure so they would cycle the action. Since I lived near Los Angeles, a friend invited me to be an extra in a movie shoot, where I saw how they do it in Hollywood. Since it would be highly unrealistic to use the military blank adapter, they use a disk with a precise hole in it, which is attached by placing it over the muzzle, and screwing the flash hider over it. It is nearly invisible, but it is not recommended to shoot ball ammo through it. A few years later, the CA ARNG issued a bulletin requiring all units to check for and remove any Hollywood blank adapters.

Wayne

[Drew P]

Yeah that’s the trick I guess to get the gas pressure up somehow which I don’t think you can do even with special powder unless you plug the barrel or ?
So the auto pistols operate by the powder jet effect and maybe a weaker recoil spring?

[Cheeto303]

Ok, this is how us grunts did it. Take a fired 5.56 blank and cut it off just above the head. We usually did it near the dotted line around the base. Take head of the case and punch the primer out. Unscrew the flash hider place the head on the end of the barrel and screw flash hider down tight. I did this all with a Swiss Army knife. Load up your blanks and shoot. Works great in an M16A1 on auto. They would fire and cycle without any hiccups and the flame that shoots the end of the barrel is awesome at night. When I was in Panama (4-10 Inf) working aggressor detail at Ft Sherman for JOTC (Jungle Operations Training Center) it would really freak people out. I would also open unfired blanks and dump the powder out into a container then trim the blank down to 19mm with the saw,file and ruler on my Swiss Army knife. Then get some Hickory or Oak twigs and whittle me out some Boolits, then fill the case about half full of the powder and seat the wood boolit. These worked great in the then new M9 Beretta's,single shot of course.One night out in the back forty of Ft. Campbell,Ky I was awakened by a scratching digging around noise by my head. I grabbed my flashlight and to my surprise there was a Bobcat about 2 feet from my head, I grabbed my M9 and killed it with a wooden boolit to the head. Anyhow those blank adapters work good but you must absolutely make sure you do not fire anything other than blanks through it. It does not work out well if you try to squeeze boolit through a flash hole. Maybe someday I'll talk about hunting small and medium game in Panama with my M16A1 some blanks and cleaning rod sections.

[WRideout]

During WWII the Germans used oversized wooden bullets in blanks that were linked for machine gun. When they went through the barrel, they compressed; as they exited, the rotational energy made them fly apart into splinters. Scuttlebutt among American GI's was that they used wooden bullets so that they wouldn't show up on x-ray.

Wayne

[Burnt Fingers]

During WWII the Germans used oversized wooden bullets in blanks that were linked for machine gun. When they went through the barrel, they compressed; as they exited, the rotational energy made them fly apart into splinters. Scuttlebutt among American GI's was that they used wooden bullets so that they wouldn't show up on x-ray.

Wayne

Those were training bullets. If the rotational energy made them fly apart it would do so very close to the muzzle.

[Bazoo]

Hornady sells blank making dies.

[fredj338]

Yeah that’s the trick I guess to get the gas pressure up somehow which I don’t think you can do even with special powder unless you plug the barrel or ?
So the auto pistols operate by the powder jet effect and maybe a weaker recoil spring?

Most pistols are recoil operated, not gas operated like the AR. I would think you need a powder that generates a higher gas output. You could use a wad over powder charge & then roll crimp the case mouth to hold it. I guess the question is why?

[Drew P]

Most pistols are recoil operated, not gas operated like the AR. I would think you need a powder that generates a higher gas output. You could use a wad over powder charge & then roll crimp the case mouth to hold it. I guess the question is why?
A wad would be a projectile on some level though. As for why, I guess just winter boredom.