.22 and muzzle flash

[FrankenCub]

Ok another question, busy mind tonight. So, I'm wondering how much muzzle flash the lowly .22LR produces as I've never shot mine at night. Is it quite substantial from unburnt powder? I'd like to try a NV scope on it for hunting instead of using lights but a lot of flash will raise hell with it for any follow up shots. Most of the flash suppressors that are effective look fairly simple. Might be pretty easy to make one that would slip fit to the barrel without needing to thread it. But, if the .22 produces too much flash would it even be worth the effort to make one?

 

[GOYABEAN]

 

[Marine Cpl]

It depends on the length of the barrel. With a 16 inch you will get very minimal flash. On a handgun, the unburnt power from the short barrel will make a bigger ball.

This video below shows more of a light streak of flash.

 

[FrankenCub]

That doesn't look too bad but a bit long, may still show a significant flash in a NV scope. My barrel is 23" though so that may have a big effect. Maybe I should just take it out a shoot it about 10:00 some night.

 

[meketrefe]

22LR doesn't produce much flash as all the powder is burned after 13, 14 inches with most loads.
It is a really small capacity and fast burning powder.
Subsonic loads with a 20" barrel or longer will not need a suppressor neither. Super quiet.
The only disadvantage with the rifles is that most will slow down the bullet vs. the ideal length that is below the 16" standard.
Same issue with the 9mm and 40 caliber pistol loads when shot from carbines.

 

[togmaster]

So what is the ideal length for a 9mm carbine?

 

[meketrefe]

So what is the ideal length for a 9mm carbine?

13 to 14" max. It is just a few fps but some loads slow down after that.
One can have a smaller barrel and then a barrel extension (pinned and/or welded) to meet the 16" legal requirement.
One additional benefit is that a extension works as muzzle protector and potential krinkov style dissipator.

 

[togmaster]

Great info.

 

[Marine Cpl]

So what is the ideal length for a 9mm carbine?

The magic number seems to be around 14 inches according to Ballistics by the Inch.

BBTI - Ballistics by the Inch :: 9mm Luger Results

 

[meketrefe]

yeah. Thanks for sharing that info.
14 inches will work well with many loads it seems.

 

[FrankenCub]

22LR doesn't produce much flash as all the powder is burned after 13, 14 inches with most loads.
It is a really small capacity and fast burning powder.
Subsonic loads with a 20" barrel or longer will not need a suppressor neither. Super quiet.
The only disadvantage with the rifles is that most will slow down the bullet vs. the ideal length that is below the 16" standard.
Same issue with the 9mm and 40 caliber pistol loads when shot from carbines.

Thanks meke. I've never used sub's for anything but I may try that for squirrel hunting closer to houses. Something else I didn't realize either, never knew this 23" barrel is actually robbing fps from me but makes perfect sense. Not that I would ever know lol. Only killin little critters with it

 

[meketrefe]

Great info.

Thanks. There is a simple formula for what we refer to as the case volume / bore volume ratio.

Basically you divide the volume of the case by the volume of the bore

Volume of the Bore = π R2 L where R is the radius (Bore /2 ) and L is the length of the bore from the mouth of the case.

Powder manufactures will give you pressure estimates by length according to the powder burn rate. The internal ballistics are a bit more predictable
with bottleneck cartriges. With straight wall cartridges it is a bit more complex as other small variables have a greater effect.

There is also the case volume to bore area ratio that is an easy way to determine if a cartrige will require longer barrels and even potentially
be over-bored.

Over-bored is considered when the case capacity is too large to be efficient and therefore resulting in excessive heat at the throat and will need
very long barrels (bore volume) for a full burn. Good examples are the 243 winchester or 7mm STW among many others.

 

[meketrefe]

Thanks meke. I've never used sub's for anything but I may try that for squirrel hunting closer to houses. Something else I didn't realize either, never knew this 23" barrel is actually robbing fps from me but makes perfect sense. Not that I would ever know lol. Only killin little critters with it

Np. I think it is good to understand what is happening and perhaps one day will help decide one round vs another but at the same time this has not
a significant impact for everyone for the typical use. You get what you get and work with it.
This would be more important for someone looking into special purpose or some sort of competition.
Also for the speed seekers that want to get the most speed from their carbines and reloads in the case of the pistol rounds.

 

[FrankenCub]

Np. I think it is good to understand what is happening and perhaps one day will help decide one round vs another but at the same time this has not
a significant impact for everyone for the typical use. You get what you get and work with it.
This would be more important for someone looking into special purpose or some sort of competition.
Also for the speed seekers that want to get the most speed from their carbines and reloads in the case of the pistol rounds.

Good information to have there. Probably wouldn't be anything I'd get into based on what I shoot but in the case of the .22 I'll have to keep that packed away in my brain. I can see a difference shooting that if I try extending my range with it. I would imagine there would be a sizable difference between a 16" and 23" barrels as they are already limited on punch. But night hunting I'd probably be best to stay with the longer barrel to minimize flash as much as I can.

 

[FrankenCub]

Ok so I had to check it out. Took my Savage 7A out back and had my stepson hold my phone. Turns out the only flash visible is coming from the chamber when it cycles a new round. It's not going to bother night vision at all, and if I lock the bolt it won't cycle so shouldn't see any flash.
Winchester Wildcats were used. I also think more flash is visible on the left side where the chamber vents are.

 

[meketrefe]

That's nothing. It looks like a firefly to me.

 

[FrankenCub]

Yeah it's not bad at all, more visible at the gun but still won't bother a NV scope.

 

[pseudonymity]

If you are hunting at night with NV I would guess the distances are relatively small so you could consider typical match subsonic rounds or even some of the specific light subsonic rounds. The really light stuff will not cycle a semi, but something like a CCI quiet might not have much flash even out of a short barrel rifle.

 

[FrankenCub]

With the .22, yes short distances. I don't want to use any subsonic ammo as I want as much punch as I can get. The only flash visible will be under the NV scope and viewing from the rifle the flash doesn't extend past my Simmons scope that's on it now, it lights up the bottom of the scope a bit but doesn't light up any portion of the barrel so the NV scope isn't going to pick it up at all. That's what I was concerned with, what the scope "seen". I think I'll be good to go with the .22.
Even worst case if I had to, the Savage 7A has a locking bolt to essentially make it a single shot.