Talk me out of a 20 inch 300 Winchester magnum… or not.

I was thinking that the barrel would be too short as Nbarta stated, but I understand that the Omega adds another 6 inches. Couple of questions if you do not mind? What bullet lengths are you planning on using? I see that a 178 grainer is still supersonic at 1400 yards and the 200 grainer at 1200 yards is basically getting close to the transonic stage too. Is this not defeating the purpose of a suppressor for hunting at shorter distances? I've never owned or shot a rifle with a suppressor so my questions are purely of the inquisitive nature.

As a man that loves the sport of shooting and hunting I will never ever talk anyone out of buying a rifle, if that is what you want go for it, but am trying to understand the practicality of the suppressed 300 win mag with a short barrel and a suppressor when most of the minimum starting loads are not even close to being subsonic loads.
Will the suppressor reduce that much noise enough to eliminate the sonic crack?
 
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I was thinking that the barrel would be too short as Nbarta stated, but I understand that the Omega adds another 6 inches. Couple of questions if you do not mind? What bullet lengths are you planning on using? I see that a 178 grainer is still supersonic at 1400 yards and the 200 grainer at 1200 yards is basically getting close to the transonic stage too. Is this not defeating the purpose of a suppressor for hunting at shorter distances? I've never owned or shot a rifle with a suppressor so my questions are purely of the inquisitive nature.

As a man that loves the sport of shooting and hunting I will never ever talk anyone out of buying a rifle, if that is what you want go for it, but am trying to understand the practicality of the suppressed 300 win mag with a short barrel and a suppressor when most of the minimum starting loads are not even close to being subsonic loads.
Will the suppressor reduce that much noise enough to eliminate the sonic crack?
There is a common misconception that suppressors are useless with supersonic loads, and I'm not sure why. Are they as quiet? No, absolutely not. They will not eliminate sonic crack as that is caused from supersonic flight, but they still eliminate a lot of the powder explosion sound

most good suppressors will get a supersonic rifle cartridge right at or maybe below OSHA's 140db heating damage limit. Even if right above you're still knocking 20+dB off the top. It's way more comfortable to shoot.

is it going to be super quiet like shooting subsonic 300 blackout or 22 subsonic, absolutely not. But it's going to essentially be like ear plugs on a full throttle win mag.
 
Having custom and made isn't cheap and not available everywhere.
His location is listed as Houston, TX. I bet there are *lots* of businesses in the Houston area and throughout Texas that do load development and it's not necessarily expensive. Though to your further point, without custom ammo something else has to give.
 
Just do it...Then send the info to Nike. (I like short barrels too). Not for mountain top to mountain top, but in the woods...yup!

Seriously, you will only know and or be happy until you do it. Buy 150gr factory loads. I would imagine they will be loaded with a faster powder for the lighter pills. Probably not going to get the range you want with the lighter pills, but shooting the heavier ones, like mentioned, you may not fully burn the powder.
Below is from Barnes Vortx line. (I would not shoot this to 800 yards as my primary but to each their own). Subtract 150 FPS and see if it meets your needs.


CartridgeRAMACIndexWT (GR)Bullet StyleB.C.
300 Win Mag21569BB300WM1150TTSX BT0.420

Velocity (FPS)Energy (FT-LB)Trajectory (inches)
MUZZLE100200300400500MUZZLE100200300400500MUZZLE100200300400500
328530442816260023932196359530872643225219081607--1.51.10.0-5.5-16.2-33.0



CartridgeRAMACIndexWT (GR)Bullet StyleB.C.
300 Win Mag21537BB300WM2165TTSX BT0.442

Velocity (FPS)Energy (FT-LB)Trajectory (inches)
MUZZLE100200300400500MUZZLE100200300400500MUZZLE100200300400500
312028992690248922982114356730812651227119341638--1.51.30.0-6.1-17.9-36.3
 
FWIW I can walk into a bass pro right now and buy 15 different types of 300 win mag ammo. They do not have a single box of wsm

personally, not a factor for me. But it seems to be a big deal for you, so I think the win mag or the 06 are your huckleberry.
 
There is a common misconception that suppressors are useless with supersonic loads, and I'm not sure why. Are they as quiet? No, absolutely not. They will not eliminate sonic crack as that is caused from supersonic flight, but they still eliminate a lot of the powder explosion sound

most good suppressors will get a supersonic rifle cartridge right at or maybe below OSHA's 140db heating damage limit. Even if right above you're still knocking 20+dB off the top. It's way more comfortable to shoot.

is it going to be super quiet like shooting subsonic 300 blackout or 22 subsonic, absolutely not. But it's going to essentially be like ear plugs on a full throttle win mag.
Thanks for the reply to my question.
 
I think you already have your answer. I agree with others to get custom loaded ammo, but as you stated, virtually everywhere they sell ammo will have a box or two of 300WM. My understanding is that is your primary concern as you don't/wont reload.
 
I did a .300 Win Mag build with a 22" barrel and I shoot it with a 5" suppressor. There might be better caliber options, but my builder specialized in the .300 WM and I wanted to stay short for the same reasons as you. I think 20" is a little too short maybe. When this gun gets re-barreled I'll probably go with a 24".

I'm getting about 2800 fps with 190 HVLDs and it's OK out to 1000 yards with a 25 MOA drop and 1640 fps and 1140 ft-pounds at that range. If I remember, I'll post a photo when I get home later today.

It's unbelievably fun to shoot. Very mild recoil (about like a .260) and easy, easy on the ears.

Oh, two mule deer (520 and 540 yds) and one elk at 200 yards haven't complained.
 
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Wow , This must be a new Fad , as I have read a few of these Big Caliber, Short Barrel things. I cant talk you out of it because you already know many of reasons that would be /could be ,considered negatives. I have a 20 inch Barrel Manlicher stocked 30-06 , and the flash( 4350 powder burning out side the bore) is considerable. IMHO, I think more barrel length would be " better " in a 300 Mag , however I'm sure there are many shooters who will say its just fine and go ahead an do it. Hell, TC chambers a pistol with 14 inch barrels that shoot full 30-06 loads, so who am I to say , its not a great idea. Please let us know when you hunt with it.
 
Hmmm... If you go Thunderbeast ultra 5 you can gain an inch of barrel, and no overall length change. If you go 300 WSM you can do the same, due to short action but ammo will be $.

I see no problems with your plan.


I think every gun is a compromise of some sort, and slightly compromising ballistics for logistics is usually wider than vice versa.
 
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Never talk anyone out of a build they want. That being said a 28 inch 308 isn't comparable to a 20 inch 300wm. The longer length for magnums is for powder burn efficiency 308 is already extremely efficient so it doesn't need tons of length to burn 42 grains of powder, but 72 grains needs more barrel length. if you want a 300wm in 20 inches go for it. You may find a dirty barrel and lower ballistics. Try to find the faster burning powders for a 300wm and you may get some better burn? As I love 300wm I'd take one in any length then work the powders to match the length
 
$20.00 a box of ammo went the way of the dodo bird. The .300 WM is over bore with a longer barrel. If you are dead set, I'd get a .300 WSM. Better yet, I would build a .30 Gibbs. I doesn't give up much to a .300 WM and it has one cartridge more magezine capacity. I'm a .300 SAUM fan, but I have plenty of ammo and brass for mine.
 
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