Gun Barrel Blackening....Fact or Crap?

...crap...

...carbon deposits were more common on and around aircraft MG/cannon ports  and can be verified in pics but usually they are overdone in scale models...

^^Ditto.^^

I'm with you on tanks and such.

Aircraft...it depends. A lot of aircraft and especially fighters tend to depict aces' rides so the guns were at least fired. And planes with a lot of area right around the muzzle (P-51s, Corsairs, Hellcats etc with the .50 cals nearly flush with the wings) would be more susceptible. 

The one that bugs me is blackening on P-47s, since the protuberances are blast tubes, not gun barrels. 

Ok cool, so it seems like we all agree so far. Appreciate the quick responses fellas.

Can't comment on Armor, but there is photo evidence of streaking on some aircraft, although most models way over do it.  I've never seen photo evidence of streaking on P-47's, but many modelers seem to confuse the blast tubes with gun barrels.

Regards,  Rick

most streaking is minimal. But I'm pretty sure it existed. Just not in quantities that you see on a lot of models. So basicially, I'm in agreement with the above answers.

rjkplasticmod

Can't comment on Armor, but there is photo evidence of streaking on some aircraft, although most models way over do it.  I've never seen photo evidence of streaking on P-47's, but many modelers seem to confuse the blast tubes with gun barrels.

Regards,  Rick

I'd go so far as to say gun streaks are overdone and environmental wear and tear, panel fading under UV light, etc, is underdone. Or overdone in the wrong way. 

Not that I'm not guilty of this myself...

Well, first of all almost all escort flights end without guns fired, in WW2. And most good crew chiefs arrange to have a/c cleaned up. And the dopies seal the ports. But if the intent is to show a fighter on the ground, steaming from a fight, fine. There could be smoke streaks.

Well I was never a tanker or gun bunny. However, I did plenty of live fire exercises around them during my time as a mech grunt , but never was close enough to notice if soot was around the bore or not. I did on one time put LOTS of rounds though our track's .50 in a very short time. That did result in some carbon around the muzzle typical of any extended automatic weapons fire as well as a discolored barrel. But I had to clean it up later.... after all a dirty weapon will jam eventually and that is not a good thing. So I would say some after lots of activity, but not overdone, and not long lived.

yes, this is 100% true, the more a tank uses its gun, the mored deposits of gases around the barrel. i have no clue y everyone else says its crap. this is a fact proved by many wartime photos.

ozzman

yes, this is 100% true, the more a tank uses its gun, the mored deposits of gases around the barrel. i have no clue y everyone else says its crap. this is a fact proved by many wartime photos.

Very interesting. If you have any pictures to show as an example, that would certainly be helpful. Perhaps I've never seen enough pictures of armor after it has extensively used its weapon, but I've not seen much in the way of photo evidence of this at all. But I'm open to it if you can show me.

ozzman

yes, this is 100% true, the more a tank uses its gun, the mored deposits of gases around the barrel. i have no clue y everyone else says its crap. this is a fact proved by many wartime photos.

You may very well be right...I would love to see the wartime photos, since I've never seen one with a blackened barrel and otherwise "clean" tank...but I haven't done a twentieth the research that others have probably done.

Thinking about the physics of it, thought...it doesn't make sense to me. The barrel is ejecting the gasses and particulates, in general, out and away from itself. On a plane, the airflow, essentially a 200-400mph wind for our purposes, forces all that back along the leading edge of the wing, leaving the gun streaks. 

With a tank, there's nothing to push the blast back, and if there was the barrel viewed, uh, barrel-on, would present very little surface area next to the leading edge and flat surfaces of a wing. A more general level of griminess, sure, but that kind of targeted accumulation just seems...difficult to me. 

Same thing applies to battleships. Look at the intensity of some of the barrages lit off up through Desert Storm...but I've never seen the New Jersey's guns half-black with carbon scoring.

Yeah, but Navy guys are cleaning those things every half-hour...

Bogus...

WIth a muzzle-brake, there would be some carbon on the inside baffles, but tubes without one are generally pretty clean...

On aircraft with blast-tubes and gun barrels extending from the wings there is little streaking...   As for escort fighters coming back with ammo and the gun-tapes in place, it's not likely...  I know that Dad's unit would expend their ammo on "Targets of Opportunity" on the way back, after they cut the bombers loose...

DoogsATX

 

ozzman:

 

yes, this is 100% true, the more a tank uses its gun, the mored deposits of gases around the barrel. i have no clue y everyone else says its crap. this is a fact proved by many wartime photos.

 

 

You may very well be right...I would love to see the wartime photos, since I've never seen one with a blackened barrel and otherwise "clean" tank...but I haven't done a twentieth the research that others have probably done.

Thinking about the physics of it, thought...it doesn't make sense to me. The barrel is ejecting the gasses and particulates, in general, out and away from itself. On a plane, the airflow, essentially a 200-400mph wind for our purposes, forces all that back along the leading edge of the wing, leaving the gun streaks. 

With a tank, there's nothing to push the blast back, and if there was the barrel viewed, uh, barrel-on, would present very little surface area next to the leading edge and flat surfaces of a wing. A more general level of griminess, sure, but that kind of targeted accumulation just seems...difficult to me. 

Same thing applies to battleships. Look at the intensity of some of the barrages lit off up through Desert Storm...but I've never seen the New Jersey's guns half-black with carbon scoring.

I'm curious about the physics of gun smoke streaking the wings of a fighter. If it is moving at 200-400 mph wouldn't most of the carbon/smoke dissipate before having a chance to cling to the wing surface? I've seen gun footage before, and there is truly a lot of smoke expelled from 6 .50 cals in the wings. I can see how the carbon would gather around the openings of the gun ports of a P-51 say, but I can't imagine they would be streaked half way down the wing. 

Doesn't airflow along the leading edge of a wing move slower than the air flowing over or under the wing? This would allow for greater carbon build up around the ports. Similar to how a ceiling fan gathers dust around the leading edge.

This is mostly my conjecture and I'm open to discussion. I'm also not saying that using this technique is incorrect. I'm just curious to know how accurate it really is. The way people build and finish a model is up to them.

ozzman

yes, this is 100% true, the more a tank uses its gun, the mored deposits of gases around the barrel. i have no clue y everyone else says its crap. this is a fact proved by many wartime photos.

If there are photos, post 'em.  I've looked at my fair share of armor photos from WWII to the present, and I've served with tanks in a fight.  Never did I notice significant deposits of carbon on the gun barrel.  HOWEVER, I do understand why people model them this way - as Oddmanrush said, it definately conveys the impression that the tank has been in the... poop...

This was a topic on another site- the poster had several photos of WWII tanks (mostly German), which were clearly "battle-hardened" and had no doubt shot off many shells, and none had any discolouration about the end of the barrel or on the muzzle brake.

I'm curious about the physics of gun smoke streaking the wings of a fighter. If it is moving at 200-400 mph wouldn't most of the carbon/smoke dissipate before having a chance to cling to the wing surface? I've seen gun footage before, and there is truly a lot of smoke expelled from 6 .50 cals in the wings. I can see how the carbon would gather around the openings of the gun ports of a P-51 say, but I can't imagine they would be streaked half way down the wing. 

Like I said earlier, the farther out from the leading edge the muzzle is, the less carbon that hits the wings...  The carbon isn't in the smoke nearly so much as it is in the muzzle flash...   The flame is what actually contains the unburned powder and carbon and if it doesn't touch the wings, it doesn't leave a trail. This is even truer of sircraft that don't have exposed mzzles, like some jets... The F-86 comes to mind..

Doesn't airflow along the leading edge of a wing move slower than the air flowing over or under the wing? This would allow for greater carbon build up around the ports. Similar to how a ceiling fan gathers dust around the leading edge.

No, the airflow actually speeds up over the wing's top surface, causing a lower air pressure and the resulting lift.... At the leading edge, the air is the same until it actually hits it...  However, the faster-moving air would  cause a streak to be longer on the top than the bottom, although the shell ejection ports would have carbon streak as well...

I gotta dig up some photos... I remember an F-86 that I saw that was almost black around the gun-ports and on the sides...  Someone had writen "MiG Killer" in the soot..

I do it because I think it looks cool.

Nuthin' wrong with that, I reckon, lol..

Hans von Hammer

 

 

I gotta dig up some photos... I remember an F-86 that I saw that was almost black around the gun-ports and on the sides...  Someone had writen "MiG Killer" in the soot..

Ok, I agree with this and it makes sense. If the muzzle flash is coming directly into contact with the surface of the aircraft I can see how there would be carbon build up like you would see on an F-86. I did an A-4 not long ago and blackened the fuselage along side the canons because it made sense in this manner, and because I'd seen it in pictures like this:

http://a4skyhawk.org/5e/g151984/html/152032.htm

http://a4skyhawk.org/5e/g151022/html/151193c.htm

http://a4skyhawk.org/5e/g149959/html/150046.htm

http://a4skyhawk.org/5e/g151984/html/152081.htm

http://a4skyhawk.org/5e/g151022/html/151045.htm

http://a4skyhawk.org/5e/g151022/html/151096d.htm

http://a4skyhawk.org/5e/g151022/html/151088.htm  (what is interesting about this photo is that clearly this aircraft hasn't been cleaned up even though its already returned from a sortie and is off to fly another. Just goes to show maintenance didn't always have the time to spruce the planes up)

as opposed to these clean ones here:

http://a4skyhawk.org/5e/g149647/html/149658a.htm

http://a4skyhawk.org/5e/g149647/html/149658b.htm

http://a4skyhawk.org/5e/g151022/html/151125a.htm

But if you notice, the streaking doesn't extend very far back along the fuselage at all. Just the area surrounding the canon for the most part.

I do it, and don't care if it's "realistic" or not--it's purely an artistic choice that conveys a feeling of having been in action, for me. But I only do it on WWII German tanks. I just think it looks cool.

Some modelers really DO overdo it though.

But if you notice, the streaking doesn't extend very far back along the fuselage at all. Just the area surrounding the canon for the most part.

 

That's because of that plate above the muzzles... It's there to keep gun-gases outta the intakes.  Jet engines don't like gun-gas...

the doog

I do it, and don't care if it's "realistic" or not--it's purely an artistic choice that conveys a feeling of having been in action, for me. But I only do it on WWII German tanks. I just think it looks cool.

Some modelers really DO overdo it though.

That is the correct answer!!!....A tank round is moving with it's gasses at around 2,400m/s. Even a howiter round is moving at 700 m/s....too fast to deposit

Looks good at 1/35.....not realistic at 1/1

Rounds Complete!!

Carbon from a gun will build up along the wings.  They would always be cleaned at the end of the flying day.  It was found that the carbon would cause corrosion and pitting on NMF aircraft.  Even when missiles, rockets, or a gun is fired, the crew chief will always clean the area around the weapon being fired.  The weapons troops would clean and lube the gun barrels at the end of the flying day.  The rocket launchers would be cleaned and lubed.  For a missile launcher the breach would be cleaned and in the case of a Sidewinder the launcher would be removed and cleaned in shop.  Rocket pods would be removed and cleaned in shop.  MER's, TER's and BRU's would be broken down and cleaned in shop. 

After a specified amount of rounds being fired from a gun, it would be removed and totally cleaned and inspected.  For the 20MM M-61A1 it was 100,000 rounds or one year which ever occured first.

No Crew Chief would ever allow carbon buildup to accumulate on his aircraft.  That would be the fastest way I know to have the line chief all over him.  He didn't want to spend the weekend on the wash rack washing aircraft for not keeping his jet clean.

I don't think that discoloration is caused by smoke so much but as it is by the flash burning the paint.. At least on the leading edges. Interior surfaces are probably discolored by the smoke residue.

the doog

I do it, and don't care if it's "realistic" or not--it's purely an artistic choice that conveys a feeling of having been in action, for me. But I only do it on WWII German tanks. I just think it looks cool.

Some modelers really DO overdo it though.

I don't disagree with this at all. I think a lot of what we do to our models may not be 'realistic' but may be necessary in order to portray an event, action, or something else like that. I was just curious if this was based on fact or mostly artistic impression. Its seems the fair answer is, well, both. Its present but over done.

Generally I don't have a problem with weathered models. I like them dirty as opposed to clean. Some rust and chipping doesn't really bother me either, whether or not it occurred in real life to that extent or not. You see, we aren't working in 1/1 scale. We don't have footage to show that our little tanks have participated in a battle, rolled through snow banks, or were drenched in a monsoon in south east Asia. No, our little models are a snap shot of certain events, historical, but also from our imagination. So in order to give a sense of action and adventure, I think its appropriate to add these little nuances to our models. Though perhaps not as subtle as some like, it lets us show a tank in the midst of a battle, a plane returning after a heated dog fight, etc. It gives the model character, and it breeds good discussion like we're having now.

Help me understand guys... I am a proud owner of .357 and .44 mag S&W revolvers.  After shooting 50-100 rounds (hell, its blast shooting those), you would see black residues around the muzzle and you got to clean them to make the stainless steel look beautiful like my wife!  I assume it is the same for the tanks and howitzers as long as it is not overdone... just little. 

If you look at the calibers (defined as barrel length/barrel diameter) of your handguns vs a tank main gun you will find that your handgun is shorter in calibers than a tank gun. In other words there is more distance to get a better, more complete burn on a tank gun vs your hand gun

Also, let us recocgnize.....a tank does not blow off 50 rounds of ammo in one sitting.....very highly unlikely. Also every chance the crew gets the clean the barrel....thus no build up

Even on a howitzer which could fire 50 plus rounds...different powder, slower velocity, less smoke and carbon. Again, the crew will punch the tube whenever it can.

Sooooo to answer your question, as I said, nope you won't see it on 1 to 1 world thus.....

See Doogs answer!

Rounds Complete!!