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nomadboi
August 24, 2004, 01:04 PM
Perhaps an odd question here, but I'm looking for advice.

I've got a bunch of blank firing semi-autos, made exclusively to fire blanks (plugged barrels, cheap construction) and the most common problem I have with most of them is spent brass getting caught in the slide as it returns forward, trapping it there.

Any suggestions on things that might help minimize this? I do try to keep them cleaned and oiled, especially since the blanks tend to be smoky and dirty, but it's harder to clean something with a plugged barrel. Otherwise, I dunno... polishing with a dremel maybe? Is it that brass might be catching in the chamber, or more likely that the slide isn't working like it should?

Thanks,
Kevin

1911Tuner
August 24, 2004, 01:09 PM
Try clipping a coil or two off the recoil springs or find some hotter blanks.
You're either getting short recoil, or the extractors...if applicable...are out of whack. Clean and oil the guns too...Blanks are pretty bad about powder residue.

Luck!

Tuner

Jason Demond
August 24, 2004, 08:07 PM
Why would any shooter want to buy a blank firing gun?

I have seen them for sale in the Sportsman Guide. For the price of one box of blanks, you could get two boxes of 9mm ammo.

Higgins
August 24, 2004, 09:11 PM
You sure it doesn't have something to do with thrust vectors, Tuner? ;)

nomadboi
August 24, 2004, 09:24 PM
I do film and theatre work. Even if I were to take the time to modify real guns to fire blanks, I couldn't legally rent them out to local productions.

Website can be seen at http://www.fightdesigner.com

Gunsnrovers
August 24, 2004, 09:36 PM
We use blank fire weapons all the time for reenacting and history channel shoots. Mostly military weapons modified for BFA. Most require that the ejector port be opened.

What to do and how to modifify depends on the semi-auto. Some require more work then others.

Are these the BFA only pot metal ones using 8mm blanks or are they real weapons that you've worked on?

Most of my experience is with Hi-Powers, 1911's, and P38's. Rifles are much easier (semi and bolt).

nomadboi
August 24, 2004, 10:10 PM
I'm using a mix of the Kimar 8mm blank guns and Voltran 9mm blank guns... more 9mm than 8, since they tend to be better made, and the shell casings look at least a little better coming out. Harder to find blanks for, though. And yes, most of them are pot metal junk, anyway. One of my Pythons I recently noticed was starting to have chunks of metal blown out by the full-load crimp blanks. Not good!

-Kevin

Gunsnrovers
August 25, 2004, 01:15 AM
You're up a creek on that. Not nearly as easy to gun smith. It's far easier to BFA a real gun then a pot metal one.

Don't have an answer for you besides tinkering. :(

Serpico
August 25, 2004, 02:39 AM
I shoot blanks all the time...I'm thinking about adoption.

The_Antibubba
August 25, 2004, 05:01 AM
This sounds like a Steven Wright joke! :D

"I like to skate on the other side of the ice."

Jim Keenan
August 25, 2004, 11:05 PM
As with any other semi-auto, the ejector may be at fault. But one other possible cause of the problem is failure to cycle the slide fully. If that is the case, and ammunition has been ruled out, it may be due to the gas escape hole being eroded or worn so that too much gas is escaping and not enough is left to cycle the action. Those little pistols are really not made for heavy use, just to fire a few shots for fun, so they don't hold up very well. If the cause is a worn escape hole, it could be corrected, but the fix would probably cost more than the gun.

Jim

1911Tuner
August 26, 2004, 05:49 AM
Jim...I don't know much about blank-firing semi-autos, but a thougt just came to me for a possible fix...depending on how large the bleed hole in the barrel is.

If erosion is the problem, how would repairing the hole by imposing a restriction work?

Holly carburetors are a little like the 1911 pistol...easily tuneable...and use
threaded jets in the metering block to allow the tweaker to quickly change fuel flow...They have a positive stop shoulder, and they're graduated in
increments very close to .001 inch in most cases. Charts are available from Holly that show the size of the holes in the different jets. They're about a quarter-inch in diameter, sold in pairs in blister packs, and aren't too hard to drill...which would allow a little trial and error. Drill...counterbore...tap...
voila! About 15 minutes on a lathe.

What think? Possible?

Gunsnrovers
August 26, 2004, 11:55 AM
Tuner, you have the answer.

We keep a handful of different taps available when we use the blank adapted 1911's, HP's, Stens, Garands, etc. The centers drilled out to various diameters. The barrels are drilled out and tapped. As the blanks can vary from batch to batch we just swap out adapters until we get the proper gas regulation. On 1911's, we open the ejector port and use a barrel with the lugs ground off. Hi-Powers and some other semi-auto designs are much easier. Most rifles, SMG's, and LMG's simply use either the drill and tap restriction or a restrictor used in combination or replacement of the flash hider.

A lot of the pot metal theater blank guns I have seen have dedicated sub caliber barrels instead. However, as Jim pointed out, the majority of these are disposable. The can and do erode quickly.

All the heavy use high end blank weapons I have seen and used are either modified live fire or are dedicated blank guns built with a combination of real gun parts and replacement blank only parts milled from high grade steel and or with subcaliber blank barrels turned from steel. Prices are, accordingly, much higher.

Due to the above, the obvious and inexpensive answer is to use revolvers, pump shotguns, and bolt actions. All my work with blank weapons is based on military use so I don't have any experience working with any of the modern and non-military designs.

The free reign the movie industry gets in terms of firearms versus the general public in California is both amazing and disgusting. It's all about the money.

nomadboi
August 26, 2004, 12:13 PM
What's your involvement in the industry?

I just started a small props rental thing up here because I got tired of renting things from out of state... realized I was paying almost purchase price for these pot metal guns from Weapons of Choice, once you added in shipping and all, so I might as well start my own collection and just rent it out for local plays and films. Which is what I'm doing, but damned if half the revolvers don't work straight out of the box, and the semi-autos are dying after just a couple uses. Guess I shoulda thought about that more before I got into this stuff.

I could try drilling them out, tapping it, putting in some other type of vent, but I'm honestly not sure the metal would hold. Threading in that kind of metal probably isn't going to be too strong, and I don't want to create a potential projectile that would go shooting out of the top of the gun.

Gunsnrovers
August 26, 2004, 12:38 PM
My primary involvement is as a reenactor, but that experience and what I have collected got me into being an extra on some History Channel stuff and a few independent films. Working with other reneactors, I regularly get to fiddle and work on the weapons we blank adapt (which is why I have never done this with modern and civillian stuff). The most modern weapon I have blank adapted is a M16. A simply restrictor that fits behind the flash hider is all it takes.

Most of the guys I know who rent and serve as armourers use either live fire weapons blank adapted or purpose built weapons. Guys like Bill Guiette in Santee, CA have created an industry making blank weapons for Hollywood, etc. His big money maker blank device is one he made that allows the military to fire the cannons in the M60's and M1's using a sub caliber round to save $.

I've seen more then a couple of pot metal guns blow up on folks. Using real weapons and quality steel really cuts back on the failure rate.

Contrary to many things I've seen on line, I have had ZERO problems with 1911's when properly set up. Fouling (they get dirtier faster) and improper restriction causes most of the blank failures I've seen over the last 12 years.

nomadboi
August 26, 2004, 01:04 PM
Problem is up here in Seattle there just isn't be budget to support a real armory... there's a very active scene, but it's all community theatre or independent film wanting to do their big bank shoot out with a total budget of $100 for props, effects, costumes, etc... stuff like that...

Sunray
August 26, 2004, 02:18 PM
Most blanks, military blanks anyway, still have the length of what would be the bullet after firing. The ejection port on most firearms is designed for fired cases only to eject. The added length of the crimp causes jamming.

nomadboi
August 26, 2004, 02:26 PM
The banks I'm using are either crimped casings (so much shorter than a real round) or have scored plastic caps at the end (which are pretty close to flush with the end of the brass).

The other thing I've tried is those Marushin or MGC replicas with the re-useable brass 'blank' shells with 5mm or 7mm caps as inserts... fun toys, but picky, and fragile (mostly ABS plastic), and the brass is expensive to replace if it gets messed up.

Jim Keenan
August 26, 2004, 10:03 PM
Hi, Tuner, Sunray, and guys,

Tuner, I thought of that, but all the guns I have seen of the type nomadboi described are made from cheap castings and, as Gunsnrovers said, they are just not up to any serious reworking. No one is going to spend $100 or so having a gunsmith fit an adjustable port on a $10 gun.

Sunray, the ejection ports on all the guns I know are large/long enough to eject a live round; they have to be so that an unfired or a dud round can be ejected.

Jim

nomadboi
August 26, 2004, 10:06 PM
Thinking about it more... the 9mm Voltran blank guns have generally been better quality than the 8mm Kimar or Bruno guns, but there isn't as much variety available. Man, I need to find an affordable, reliable blank fire Glock...

Gunsnrovers
August 26, 2004, 10:26 PM
I would think a Glock would be pretty easy. Get a spare barrel and tap it for a restrictor, but I'm just talking. As I said, the "newest" semi-auto I've fiddled with was a WWII Inglis Hi-Power.

A cheap Rossi, Ruger, or older S&W would be great too. A decent used one could set you back under $175. I don't think the blank guns are that much cheaper in the end. Decent .38 blanks are safe and can be pretty dang loud.

nomadboi
August 26, 2004, 10:43 PM
I'm just breaking in to the whole 'real gun' thing, having gotten in to this all via theatre/film and stage combat... started out with swords... I'm still pretty hesitant to fiddle with things that explode...

Jim Keenan
August 27, 2004, 10:05 PM
For many purposes, a real gun, even one converted to fire blanks, is just not a good option. In the first place, it will be expensive, and it will require all the paper work involved in buying any other gun, so that someone will have to take responsibility for it. It will also be a legal hassle in many areas if the gun is to be loaned or rented to someone other than the registered owner.

Even if the gun is converted for blanks, changing it back to use live ammo may be a simple matter of swapping barrels or drilling out the restriction, so it needs to be handled and secured like any gun. Worse, a normal gun firing blanks can lethal and there have been people killed accidentally with them. One of the small "blank" pistols could be dangerous but would be unlikely to be lethal.

In most theatrical situations, a lot of realism is not needed; the "murderer" pulls the gun, shoots the "victim" and the play goes on. No closeups, no replays, no one really caring whether the gun looks real or not. In fact, it is not uncommon in the theater for the gun to be a dummy with the noise of the shots being provided by the orchestra drummer or an ASM with a clapper.

Jim

nomadboi
August 27, 2004, 10:55 PM
Yep, trust me, that's my preference for live theatre. I've got my share of rubber or airsoft guns, and the gas blowback for film... but some directors are really insistent on wanting shells flying, smoke and flash, etc.

But yeah, my preference is definitely for no real guns.

Gunsnrovers
August 27, 2004, 11:13 PM
That would explain why prop masters do charge what they charge. Typically, no guns until the actual seen. Just before scene starts, insert gun. As soon as scene ends, gun is removed. At least in my experience.

There are certainly issues with using a converted firearm. However, as you've discovered, there are some issues with the alternatives as well.

Good luck.

Jim Keenan
August 28, 2004, 09:16 PM
A lot of movies made today don't use real guns at all. After a couple of infamous cases where bankable stars blew out their own tiny brains with blanks, insurance rates have gone sky high when blank guns are used in a movie. So a lot of producers will arm the "combatants" with dummy guns and let Industrial Light and Magic or someone like that add the flash and the noise afterward to the digital master, the same way the Star Wars "light sabers" were done. That is why in a movie you sometimes see guns going off but the "muzzle flash" is not at the muzzle; the computer tracking got a bit off.

Plus, real guns, even to rent, are expensive and if damaged can add to the bill. "Band of Brothers", for example, used mostly dummy M1 rifles; some even had a hole in the top so the actor could insert a dummy "clip". When the old "cowboy" movies were made, an 1873 or 1892 Winchester could be dropped in the dirt, or a Colt SAA could go over a cliff with few concerns. Today, that Colt is worth a couple of grand, and even clones are too costly to throw around.

Jim

nomadboi
August 28, 2004, 10:59 PM
Yep. A lot of the lower budget Indie films are shot on digital video anyway, which makes it really easy to edit in effects... the current guy I'm working with really wants blanks though, for a variety of reasons. Otherwise, GAS-BLOWBACK AIRSOFT! Totally the way to go.