ejumicate me... fireballs. [Archive]

Caduceus

12-17-14, 19:19

Why do some rounds cause fireballs and others don't?

Yesterday I was shooting a 10.5 inch pistol, using PMC Xtac 55gr ammo. About 25% of the rounds caused a noticable fireball. I assume this is unburned powder igniting after leaving the barrel? If so, why the randomness of it? no difference in lot numbers, and all 40 rounds were from 2 new boxes of ammo.

Thanks for fixing my curiousity.

militarymoron

12-17-14, 19:40

what muzzle device?

Leaveammoforme

12-17-14, 20:22

Yes, unburned powder. I've always been under the impression that the correct ratio of oxygen isn't always present for a burn. Similiar to first round pop from a suppressor. Once you burn the available oxygen you have to wait for more to show up.

Caduceus

12-17-14, 21:57

what muzzle device?

Standard birdcage. A2, right?

militarymoron

12-17-14, 22:12

Standard birdcage. A2, right?

Yup. I was just wondering as some muzzle devices can contribute to occasional fireballs. I'm not sure what the exact cause of the phenomenon is, but was told that some devices get carbon build up inside them after a few rounds, then that reaches a certain point when particles break off and ignite.

Leaveammoforme

12-18-14, 01:07

What I got from OP:

10.5 inch barrel + 55 grain projectile (gonna go out on limb and assume .223/556)= Fireball

An over the counter 223/556 loading will not completely burn in a 10.5 inch barrel. If it did, a 10.5 inch barrel would have the same (probably higher) muzzle velocity of a 20 inch barrel. We know a 223/556 10.5 does not perform that way.

If the fireballs were on a 16 or 20 inch, I would agree that there is some MD voodoo going on or there is an ignition problem.

Pappabear

12-18-14, 01:59

We loaded some 62 gr with H335 and it was like the 4th of July. Some powders are more " entertaining" than others as well. Obviously the short barrel is a huge part of the explanation.

markm

12-18-14, 07:08

Yup. I was just wondering as some muzzle devices can contribute to occasional fireballs. I'm not sure what the exact cause of the phenomenon is, but was told that some devices get carbon build up inside them after a few rounds, then that reaches a certain point when particles break off and ignite.

I'm going to call BS on whomever said that. I'd guess that the brutish primers used to make ball powder light are yielding inconsistent ignitions. And the result is intermittent flashing.

militarymoron

12-18-14, 09:14

I'm going to call BS on whomever said that.
eric kincel told me that in a conversation when we were discussing why he went with a more open design for the BCM comps vs. smaller holes/slots. note that he mentioned that it was a 'contributing factor' ; obviously not the main cause of fireballs. a few years ago, LAV was at our range and also speculating why we were seeing the occasional fireball with a battlecomp, and whether it was ammo inconsistencies or something to do with the muzzle device.

markm

12-18-14, 10:16

eric kincel told me that in a conversation when we were discussing why he went with a more open design for the BCM comps vs. smaller holes/slots. note that he mentioned that it was a 'contributing factor' ; obviously not the main cause of fireballs. a few years ago, LAV was at our range and also speculating why we were seeing the occasional fireball with a battlecomp, and whether it was ammo inconsistencies or something to do with the muzzle device.

Well ESK is a pretty smart guy. I wonder if it could be a combo of carbon particles, the build up on the device altering muzzle blast flow, and ammo fluctuations too.

It'd be interesting to run a Magneto speed at night and compare the velocities on flashy rounds to the velocities on non-flashy rounds.

colt933

12-18-14, 20:30

Sometimes you see sparks, sometimes it's just a big flame/fireball. I wonder if the sparks could be carbon residue breaking loose. Also, sometimes I see sparks exiting titanium suppressors, and I think it's the titanium - maybe dust left over from the manufacturing process.

militarymoron

12-18-14, 20:59

Well ESK is a pretty smart guy. I wonder if it could be a combo of carbon particles, the build up on the device altering muzzle blast flow, and ammo fluctuations too.

It'd be interesting to run a Magneto speed at night and compare the velocities on flashy rounds to the velocities on non-flashy rounds.

i'd be interested in seeing that as well. yup - ESK is a sharp dude so when he talks, i listen, ask questions, then listen again :)

it's an interesting question though, and the phenomenon still seems to persist with both 'good' ammo and the stuff like wolf. maybe try a mag of your best hand loads, minimize any ammo fluctuation and see if you get random fireballs still?

As leaveammoforme mentioned on the first page, LAV also speculated about it being similar to first round pop; related to oxygen or unburnt powder in the barrel. i found this video that illustrates the randomness of muzzle flash. no info at all on what ammo he's using, but we've all seen this sort of random flash before.
https://www.youtube.com/watch?v=0ZeATz9Vqwc

markm

12-19-14, 06:38

Yeah. Inconsistent oxygen in the barrel is a good possibility too.

Ned Christiansen

12-19-14, 07:28

I have always attributed random red sparks to being carbon particles breaking loose. You'll get that even with the King of Flash Hiders (in my book anyway), the Vortex.

sevenhelmet

12-19-14, 07:29

I've seen this from a 16" barrel AR on an indoor range with a standard A2 FH as well, shooting American Eagle 55 grain ball round. Every 3 to 5 rounds would be an especially bright flash (bright yellow), no apparent correlation with firing rate or gun temp. We never came up with a decent reason why. I've never seen it before or since, probably because I normally use outdoor ranges.

markm

12-19-14, 08:20

I wonder if it's unique to ball powders.

RVTMaverick

12-19-14, 09:59

I think it would be interesting to see IF it still happened with waiting min. 3 seconds to as much as 5 seconds between firing off rounds, giving plenty of time for unburned power to clear
away from the muzzle....?

Caduceus

12-19-14, 18:25

i'd be interested in seeing that as well. yup - ESK is a sharp dude so when he talks, i listen, ask questions, then listen again :)

it's an interesting question though, and the phenomenon still seems to persist with both 'good' ammo and the stuff like wolf. maybe try a mag of your best hand loads, minimize any ammo fluctuation and see if you get random fireballs still?

As leaveammoforme mentioned on the first page, LAV also speculated about it being similar to first round pop; related to oxygen or unburnt powder in the barrel. i found this video that illustrates the randomness of muzzle flash. no info at all on what ammo he's using, but we've all seen this sort of random flash before.
https://www.youtube.com/watch?v=0ZeATz9Vqwc

Well, in this context it is random. Others, like a Mosin M-44, are just shy of a flash-bang...

Interesting thoughts all. Thanks for the info, and glad I'm not the only one slightly confused by it.

JHoward

12-19-14, 18:37

Mine mostly does it with XM193. This is an A2 FH and XM193. I just installed an ALG SCB, so I will try to get a low light condition and do the same video with two different ammo's.

https://www.youtube.com/watch?v=7y0k4zyXU1U

Also, I would have to disagree that these big flashes are carbon breaking off and igniting, maybe the sparks that are sometimes visible when the large flashes are not. These shots you see in this video are within the first 100 rounds this rifle has ever seen.

markm

12-19-14, 19:27

Also, I would have to disagree that these big flashes are carbon breaking off and igniting, maybe the sparks that are sometimes visible when the large flashes are not. These shots you see in this video are within the first 100 rounds this rifle has ever seen.

That looks a classic example. I've found, however, that video doesn't always capture flash that the eye can see... but maybe that's just my crappy video gear. ;)

JHoward

12-19-14, 19:43

Not always for sure. This is taken with an outdated android phone. Hah! So it's not really video gear. I would say that it caught most of the flashes though. I think being such low light, that may have helped. It was basically completely random. I always thought it was as the barrel heated, but it doesn't seem to be the case.

markm

12-20-14, 06:54

Might be better than what I've tried to use. I can remember wanting to get footage of a specific flash hider, and the video wouldn't capture what I was seeing with my eyes.

futurerider103

12-22-14, 10:01

RVTMaverick

12-22-14, 10:08

I was shooting 62gr ZQ1 FMJ out off my 18hbar with a non threaded barrel why such a fire ball on mine then?

http://youtu.be/28i7-OLTTzM

Hey futurerider,

I Still >think< the design of .223/5.56 round was with a FH in place.... Yes/No? And from the sounds of it, yours doesn't have a FH screwed on...

I can not watch your video here from work...:(

Peace Jeff

futurerider103

12-22-14, 10:10

There is no fh on mine at all.

markm

12-22-14, 10:14

Now that I think about it, I see the same variability on flash out of pistols in low light too.

futurerider103

12-22-14, 10:20

I haven't noticed this out of any at my other rifles and I shoot .308, .270, 7.62x39, 30-06, and of course .22

steyrman13

12-22-14, 10:31

I notice it with several of my bolt guns. I typically am shooting them at dawn or dusk (Deer hunting) and will notice it with the same lot of ammo having different volume of fireballs (Without a flashhider to have the carbon deposits on). I would think the sparkles would be the carbon flakes braking off, while the fireball would be build up of gases or oxygen. I typically notice it happens in sequential firing schedule and usually around round 4 or 5 (WAG) as I have never actually counted and written it down, but it seems that it was usually 3-5 rounds in between the larger flashes. I too notice it with handguns as well.