Anyone know if it is possible to get a subsonic round out of a 300 WM with a 190 grain bullet? Buddy just bought a suppressor and the maker said that 190 grains was all he could shoot without voiding his warranty and/or risk not stabilizing the bullet enough to pass thru the suppressor. I can't remember off hand what twist the barrel is but I would assume 1:11. We are going to reload for it but just wondering if it is an option and if anyone has done it before.
Subsonic 300WM w/ 190 grain bullets
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Dr. Tad Hussein Winslow
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You certainly CAN, but the question is, how much work will you have to do to find that spot of just the right amount of the right powder, while walking that fine line between supersonic and a bullet stuck in the barrel - the latter of which is very, very bad if you don't recognize it, and fairly bad if you DO recognize it. It'd just be a lot of trial and error unless someone's already done the research for you on the net somewhere for that particular barrel length, twist rate, and bullet choice.
But as a starting point, Lyman's 49th shows a 190 gr cast lead alloy bullet to be pushed to just 1,599 fps with 40.0 gr of IMR-4831, and 1,609 fps with 18.0 gr of Unique. These are some of the listed starting loads. Now, you just need to work down to 1,050 without sticking a bullet in your barrel.
But as a starting point, Lyman's 49th shows a 190 gr cast lead alloy bullet to be pushed to just 1,599 fps with 40.0 gr of IMR-4831, and 1,609 fps with 18.0 gr of Unique. These are some of the listed starting loads. Now, you just need to work down to 1,050 without sticking a bullet in your barrel.
i've taken a 300 wsm subsonic. i used unique, and it worked ok, but stability (tumbling) is an issue. i was having some pretty erratic ignition until i switched over to mag primers. unique + mag primer wasn't perfect, but did pretty well.
would also suggest having a look at trail boss, and the sr-series of powders. good luck!
would also suggest having a look at trail boss, and the sr-series of powders. good luck!
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jjohnson
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Reload?
Oh, man, that's easy if you're a reloader. You can take many rifle cartridges subsonic pretty easily - a few can be finicky when you get way down to 700 fps and lower, because tiny loads in big hulls can be erratic sometimes with certain powder combinations. I'm sticking with the theory that igniting a very small charge in a very large rifle cartridge is where you run into trouble.
As Doc Winslow pointed out, if you're playing around with low powder charges on your own, getting a bullet stuck in your barrel is annoying if you notice it - and dangerous if you DON'T notice it.
In general though, you can either use Unique or one of the powders really developed for the cast lead boys (like 5744) and run 'em up to 1050 fps or so. I pick 1050 because when you're looking at "subsonic," you have to consider the deviations in velocity from one cartridge to the next, you want EVERY shot to be subsonic - so you have to factor the standard deviation as the error margin.
I've had limited experience with Trail Boss, and it's been good, but I haven't loaded the cartridge in question.
If you have a particular bullet and powder in mind, you might find one of us nice guys in the reloader's forum to run it through our ballistic software to get you in the right ballpark.
Oh, man, that's easy if you're a reloader. You can take many rifle cartridges subsonic pretty easily - a few can be finicky when you get way down to 700 fps and lower, because tiny loads in big hulls can be erratic sometimes with certain powder combinations. I'm sticking with the theory that igniting a very small charge in a very large rifle cartridge is where you run into trouble.
As Doc Winslow pointed out, if you're playing around with low powder charges on your own, getting a bullet stuck in your barrel is annoying if you notice it - and dangerous if you DON'T notice it.
In general though, you can either use Unique or one of the powders really developed for the cast lead boys (like 5744) and run 'em up to 1050 fps or so. I pick 1050 because when you're looking at "subsonic," you have to consider the deviations in velocity from one cartridge to the next, you want EVERY shot to be subsonic - so you have to factor the standard deviation as the error margin.
I've had limited experience with Trail Boss, and it's been good, but I haven't loaded the cartridge in question.
If you have a particular bullet and powder in mind, you might find one of us nice guys in the reloader's forum to run it through our ballistic software to get you in the right ballpark.
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