Help please! .223 reload large flash

[Jsummers]

[noylj]

Did you retrieve the case and inspect it?
Did you tear down and inspect the rifle?
Some powders have higher MUZZLE flash, but ejection port flash?

[baih777]

Did you save the brass ?
Was it a blown primer ?

[sofbak]

1. Were rhe exterior surfaces of your fired cases covered with soot or carbon deposits-especially at or behind the neck/shoulder?

2. Is your rifle .223 or 5.56 NATO caliber?

https://www.hornadyle.com/resources/le-faq/what-is-the-difference-between-556-nato-and-223-rem-ammunition

[Jsummers]

[Jsummers]

The excessive flash may not have been out the ejection port. I was shooting by myself and it may have been out the muzzle and reflected off the side wall at the range.

[racinjason233]

I run 25 grains everything the same except primer and h335 does have a significant flash out of a mini 14 at indoor range. I didn’t notice a bright flash in the desert with AR platform but it was sunny.

[slamfire1]

How could you see the flash? Did you shoot at night?

No, you were not seeing things that were not real. All semi autos are designed to unlock at pressures just below the bursting strength of brass. This is called the residual blowback effect and is delibrate. Designers want to increase the amount of time energy is available to function the mechanism. You could read The Machine Gun Vol IV by Chinn to understand how this works, but, no one reads books anymore. They just quote in print shills, or clueless individuals on the internet.

This is a blast from the past, this is actual pressure curve versus displacement for the Garand gas system. If you are smart enough to read a graph, you can see that unlock is occurring around 2.25 milliseconds when pressures are less than 650 psia.


The timing of your mechanism is going to be similar.




from Chin



Since pressures are not zero, some burning powder is going to come out the chamber. You can verify this affect with your semi auto 22lr rim pistol or rifle. These mechanisms leave a lot of condensed wax and gunpowder in the breech. This is due to the gunpowder, and melted wax lube on the cases, going up the barrel, and back out of the breech, when the case is extracted. You can read in Chinn how these pure blowback actions work in principle. Anyway, given peculiarities of light and gun powder burn rate, under certain conditions you will see a "flash" as the case is removed from the chamber. It is rare to see this.

I have never seen flash out of any of my weapons, but I don't use H335 in the AR15 mechanism. I used IMR 4895, Varget, AA2520, N140 and N135. I also, never fired at night. Based on a burn rate chart, H335 ought to be just great, so heck if I know why you are seeing anything.

What matters most, does your rifle feed and extract the cartridge without excessive pressure indications? If the rifle reliably feeds and extracts, accuracy is what you want, then don't worry about breech flash.

Be very cautious about increasing powder charges. You might want to decrease the powder charge and see if that has an effect on the flash. Since I am not familiar with your powder I have no idea what charge level to use.

However, always, always, wear shooting glasses. It is far better to be wearing glasses when a hot blast of oily gas comes out of the mechanism. **** happens.

[kcheung2]

The excessive flash may not have been out the ejection port. I was shooting by myself and it may have been out the muzzle and reflected off the side wall at the range.

If the flash came out of the ejection port that implies an out of battery detonation, and if that were the case you'd definitely know it by the broken bits of your gun flying around. I agree with your 2nd idea that it was from your muzzle, either reflected off the wall or direct line of sight. You have a brake on the muzzle, right? Those things can propogate fireballs.

With proper lubing, sizing 223 cases takes very little effort. That has nothing to do with the flash you observed, just pointing that out.

[the86d]

Overlube a case, and see how nice it... slips... right... in...
and back out again...

[Jsummers]

Thank you all for your input. I’ll slow down and triple-check things; maybe have someone video my shots to see where from and how excessive the flash is. I figured that I would err on the over paranoid side since things can go boom in a bad way.

[baih777]

Keep an eye on the primers.
Go to a 99cent store. Magnifying glass for 99cents. I keep one in my bag and a couple at home.