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300 Win Mag Muzzle Flash, Max Powder Burn & Muzzle Device Selection

coolbreeze91

Private
Minuteman
Jul 5, 2022
10
1
Cleveland Ohio
Hey all,

The purpose of this post is to assist in determining barrel length and muzzle device combination for an M40A5ish build in 300 win mag for tactical application whereas flash signature reduction unsuppressed is placed higher in priority than recoil mgmt.
This rifle will be married to a Deadair Sandman Series can and will be using either a keymo brake or flash hider.

As it stands, the build is a 24” barrel with a keymo flashhider. However, after suggestions for a brake were made to tame recoil, it got me thinking, how flashy will this thing be unsuppressed and is it possible to run a brake with little or no flash. If I can use a muzzle brake without emitting a huge signature and also without adding several inches to the rifle length then this would be ideal but if not, its likely this will get a flash hider like everything else in my quiver.

My rifles are built around the concept that the rifle itself should emit minimal flash signature and in the event the suppressor is no longer an option, it can still function without emitting a huge flash signature. Call it a personal preference. Never has reduced recoil been a reason for me to sacrifice signature reduction; however, having never fired a 300 win mag its hard for me to really understand if my capabilities will suffer due to recoil on this system.

So to put this into a couple specific questions;

-What barrel length is required for max powder burn in typical tactical use 300 win mag rounds? (roughly)

-What barrel length is required for minimal flash using a keymo brake?

-Anyone out there with experience on a similar setup?

(We won't go as specific as to what rounds for the sole purpose that I do not have the tech knowledge on 300 win mag rounds yet so with that,I understand data will vary, but again lets assume tactical application as intended use and rounds to match.)
 
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All I can say from roughly 4 years of shooting a 300 WM is that; A 300 WM has ha huge muzzleflash with a bare barrel. It is also VERY loud with a brake only, earplugs and ear pro on top is adviced. With a suppressor, the 300wm becomes managable but you still need to put some effort into it, atleast that is what I found, beeing used to regular SA calibers prior to getting the wm.

I ran a 26" factory barrel at first, had a huge muzzleflash. Had to get it threaded and put on a suppressor wich made all the difference.
After about 2 years I had it rebarreled with a 29" barrel, which shot great but as you can imagine, made the rifle very cumbersome. Had it cut down last year to 22" in front of the recoil lug, did not loose as much muzzle velocity as anticipated and stil shot great, maybe better. But man was it loud with only a break. Sold the rifle about a month ago now, no regrets.

To answer your questions, I would not get a longer barrel than 26", a 22" gave me no issues and plenty of speed.
There is no such thing as minimal flash when a 300WM is on topic. Its a magnum and you are setting off over 70 grains of powder every time you squeeze the trigger.
 
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As to your barrel length question that depends on the powder used. Outside powders with added flash suppressants burn length would need to be determined with QuickLoad or another tool.
 
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All I can say from roughly 4 years of shooting a 300 WM is that; A 300 WM has ha huge muzzleflash with a bare barrel. It is also VERY loud with a brake only, earplugs and ear pro on top is adviced. With a suppressor, the 300wm becomes managable but you still need to put some effort into it, atleast that is what I found, beeing used to regular SA calibers prior to getting the wm.

I ran a 26" factory barrel at first, had a huge muzzleflash. Had to get it threaded and put on a suppressor wich made all the difference.
After about 2 years I had it rebarreled with a 29" barrel, which shot great but as you can imagine, made the rifle very cumbersome. Had it cut down last year to 22" in front of the recoil lug, did not loose as much muzzle velocity as anticipated and stil shot great, maybe better. But man was it loud with only a break. Sold the rifle about a month ago now, no regrets.

To answer your questions, I would not get a longer barrel than 26", a 22" gave me no issues and plenty of speed.
There is no such thing as minimal flash when a 300WM is on topic. Its a magnum and you are setting off over 70 grains of powder every time you squeeze the trigger.
By the sounds of this you have me considering permanently suppressing this and using a brake to help the life of the can. If I went this route I may even drop the barrel length down.

I love the added power and range of the 300 wm but maybe dropping it back down ro 308 isn’t a bad idea.
 
By the sounds of this you have me considering permanently suppressing this and using a brake to help the life of the can. If I went this route I may even drop the barrel length down.

I love the added power and range of the 300 wm but maybe dropping it back down ro 308 isn’t a bad idea.
Well, others may say different but the above pretty much sums up my experience. I shot around 1700 rounds with my 300 wm during the years I had it. Previously Ive had rifles in 308 winchester, a 6,5x55 swede and a 6,5x47L and from that experience I can say that the 300 WM is a very different beast.
Now the only centerfire rifle I have is a Sako TRG 22 in 308 winchester. To me, its the perfect rifle, it does everything I could possibly need and it does not beat me up in the process. It shoots great and the trigger is the best availabe IMHO.
And I think you would do well with a supressor for the 300wm, if you get one.

oh, and if you get a 300WM, buy as much Hodgdon H1000 powder as you can find for it. Its definitely the best powder I ever tried with it.
 
I seriously doubt you'll be able to eliminate muzzle flash without a comprehensive suppressor. A muzzle brake won't eliminate the flash, but simply redirect it. The length of the bbl you've selected will likely not allow the powder to fully burn prior to the bullet leaving the bbl. Even a standard 26" produces a falsh like a volkswagon headlight. Simply, you're not going to eliminate the flas, so you may as well choose a bbl length relative to the accuracy at distance desired. Something else to consider, permanently supressing it; muzzle flash equates to serious residue build-up internally.
 
I seriously doubt you'll be able to eliminate muzzle flash without a comprehensive suppressor. A muzzle brake won't eliminate the flash, but simply redirect it. The length of the bbl you've selected will likely not allow the powder to fully burn prior to the bullet leaving the bbl. Even a standard 26" produces a falsh like a volkswagon headlight. Simply, you're not going to eliminate the flas, so you may as well choose a bbl length relative to the accuracy at distance desired. Something else to consider, permanently supressing it; muzzle flash equates to serious residue build-up internally.
I ended up going with a 25” barrel. Dead Air flash hider and will marry it to a Sandman L. We’ll see how she performs. You can’t have everything in a weapon system and that’s a hard lesson Iv never learned. Im not concerned about the recoil given the overall weight of the system will be pretty heavy. We'll see how it plays out. Thanks for the response. I definitely am still curious about what barrel length is needed for max powder burn in a common round. Even if it is unrealistically long.
 
I solved the 300WinMag flash issue with a TBAC 338 suppressor .

Almost no recoil and strangely quiet….
1028DE05-880E-4012-A5B4-16613054331E.jpeg
 
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