Short barrel cartridge help!

I live and hunt in Wyoming, and hunt with my cousin often, he has a 25" .270 Sherman, and built a 19" .270 Sherman for his wife, both supressed. I did load developement for both, and helped build both, as well as a 24" 7 mag with supressor. Yes, it's doable hunting out here, but we also go hunting in back country for mulies and elk, packing in 5+ miles at times, having to go over logs, under limbs, cross creeks, and ride horses. Our elk taken over the last 4 years have averaged over 700 yards where we hunt. Having used those three rifles, as well as my wife's 20"+brake 7 Max, my 24"+brake .338 Norma, and my 29"+brake .260 ai.....

I am building a 20" 30 nosler with a carbon barrel on an XLR folding magnesium Atom chassis to be run exclusively supressed. Getting a 215 to 2900 or so seems doable in a 20" 30 nosler, from other people's data I have seen, and will get me what I need for elk out to 1000+ where I hunt.

When it comes to performance, you will have a bunch of people talk about how a 20" big magnum cartridge will get the same performance as a standard bolt face short action cartridge, what I have found is the vast majority of these people have zero first hand experience, and they are simply wrong. A 20" .308 will not keep up with a 20" 300 wm, 300 prc, 30 nosler, 300 rum, etc......and I'm not sure why so many people are 100% set on trying to convince others it will when they haven't done it. Talk to the specialty pistol guys, they will set ya right when it comes to short barrels. Most other people are just guessing because most haven't done it.

As for your specific use, I would stray away from the 6.5, a 20" 6.5 prc won't exactly be an optimal 800 yard elk round. I would look at a 7mm as a minimum, and prefer a 30 cal. I am assuming you want to keep weight relatively light, and also assuming your can is a .30 cal Max, and will not be appropriate for a .338 anything. If heavier weight rifle and a .338 cal can were in the conversation that may change some things....

A 7 SAUM isn't a bad option, and is where I would start my search for an acceptable cartridge. A 7 WSM, 7 rem mag, 28 Nosler, 300 SAUM, WSM, Win Mag, 30 nosler, 300 PRC, 30 Sherman Mag, or possibly rum is what I would look at, depending on what your specific can is capable of managing. Determine what performance you want at your max range, then do your research and look for first hand load data, from multiple sources, on short barreled performance of a specific cartridge. I wanted an elk capable cartridge to over 1000 yards with the 20" tube, that put me on a 30 Nosler. For 800 yards, and since you already have the components for one, I would strongly consider another 300 WSM

Keep in mind, this is coming from a guy that has bang-flopped elk at 890 yards with a high lung, just below spine shot from a .260 Ackley, actually my .260 AI has taken 5 elk all between 703 and 940 yards, so I am fully aware that it is capable, and a 20" 6.5 PRC may be similar to my 29" .260 AI (156 @ 2940), so it would do it, but 7mm seem to put them down better, and 30 and .338 cals seem to step it up even more.
Thank you for such an in-depth response. Soo much to think about in that post.
 
I feel like this is the direction I'm going with rifles just feeling too long. Unfortunately many of mine are carbon barreled so I can't chop them. They will likely be sold for other options at some point.

Nice Sheep in your pic btw!
I think a 7WSM will get you what you want with a 20" barrel running the 180 Berger.
 
I live and hunt in Wyoming, and hunt with my cousin often, he has a 25" .270 Sherman, and built a 19" .270 Sherman for his wife, both supressed. I did load developement for both, and helped build both, as well as a 24" 7 mag with supressor. Yes, it's doable hunting out here, but we also go hunting in back country for mulies and elk, packing in 5+ miles at times, having to go over logs, under limbs, cross creeks, and ride horses. Our elk taken over the last 4 years have averaged over 700 yards where we hunt. Having used those three rifles, as well as my wife's 20"+brake 7 Max, my 24"+brake .338 Norma, and my 29"+brake .260 ai.....

I am building a 20" 30 nosler with a carbon barrel on an XLR folding magnesium Atom chassis to be run exclusively supressed. Getting a 215 to 2900 or so seems doable in a 20" 30 nosler, from other people's data I have seen, and will get me what I need for elk out to 1000+ where I hunt.

When it comes to performance, you will have a bunch of people talk about how a 20" big magnum cartridge will get the same performance as a standard bolt face short action cartridge, what I have found is the vast majority of these people have zero first hand experience, and they are simply wrong. A 20" .308 will not keep up with a 20" 300 wm, 300 prc, 30 nosler, 300 rum, etc......and I'm not sure why so many people are 100% set on trying to convince others it will when they haven't done it. Talk to the specialty pistol guys, they will set ya right when it comes to short barrels. Most other people are just guessing because most haven't done it.

As for your specific use, I would stray away from the 6.5, a 20" 6.5 prc won't exactly be an optimal 800 yard elk round. I would look at a 7mm as a minimum, and prefer a 30 cal. I am assuming you want to keep weight relatively light, and also assuming your can is a .30 cal Max, and will not be appropriate for a .338 anything. If heavier weight rifle and a .338 cal can were in the conversation that may change some things....

A 7 SAUM isn't a bad option, and is where I would start my search for an acceptable cartridge. A 7 WSM, 7 rem mag, 28 Nosler, 300 SAUM, WSM, Win Mag, 30 nosler, 300 PRC, 30 Sherman Mag, or possibly rum is what I would look at, depending on what your specific can is capable of managing. Determine what performance you want at your max range, then do your research and look for first hand load data, from multiple sources, on short barreled performance of a specific cartridge. I wanted an elk capable cartridge to over 1000 yards with the 20" tube, that put me on a 30 Nosler. For 800 yards, and since you already have the components for one, I would strongly consider another 300 WSM

Keep in mind, this is coming from a guy that has bang-flopped elk at 890 yards with a high lung, just below spine shot from a .260 Ackley, actually my .260 AI has taken 5 elk all between 703 and 940 yards, so I am fully aware that it is capable, and a 20" 6.5 PRC may be similar to my 29" .260 AI (156 @ 2940), so it would do it, but 7mm seem to put them down better, and 30 and .338 cals seem to step it up even more.
Curious what type of chamber you are running on this 30 Nos. SAMMI or custom.
 
I have got to ask this. IF you are shooting a supersonic round why are you using a suppressor? Hearing protection I sort of understand but as for the rest I don't get it.

I hunt subsonic and use a suppressor so understand I'm not opposed to suppression while hunting.

Looking for some learning here.
For me, it is 3-fold.
1. No hearing protection required while hunting. No ringing ears after the shot, can communicate in a whisper before the shot, can hear the "whop" of a hit.
2. Game (either target animal or bystander animals) have no clue someone is shooting if they are more than 100 yards away, so no spooking them. Have had bystander animals stand around after the shot and the target animal goes down. Usually, the "whop" on impact is louder to the ears than the shot.
3. Other HUNTERS don't hear you shoot if they are more than 100 yards away. To me, this is a big bonus in some pockets I hunt.
 
Curious what type of chamber you are running on this 30 Nos. SAMMI or custom.
Nothing yet, as stated, I am building it. I plan on having it throated longer than SAAMI, I need to run some numbers, as I plan on trying the Badlands 205 SBDII first. If that bullet doesn't shoot as well as desired, I have a couple others in mind, but I want to throat it so it will work for a few of my choices.
 
Which do you have?
have 2, they are fairly long at 11" but dont even add 4" to the barrel length. stainless baffles that can be replaced individually. as quiet as you'll get sensibly. they are light for a modular supressor. ill take the extra grams over a sealed unit.
 

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have 2, they are fairly long at 11" but dont even add 4" to the barrel length. stainless baffles that can be replaced individually. as quiet as you'll get sensibly. they are light for a modular supressor. ill take the extra grams over a sealed unit.
Could you put one of those over top a carbon barrel?
 
You loose approximately 25 fps for every inch of barrel you cut off. That is standardized across all cartridges. Some will loose more, some less but that is a good rule of thumb. Every rifle is different. I have a 18" 7mm-08 that unsurpressed will shoot 150s at 2650 with a break. If we try to push them any fast we run into issues with the unburnt powder. With a 6" suppressor on we are getting just over 2700. The suppressor allows us to turn it up a little more without accuracy issues. After we do that with a few more grains off powder we are right around 2750, which is essentially what you would get out of a 22-24" rifle in the same caliber. I should have qualified my statement more. I run 42.5 grains unsuppressed which is the max I can get and maintain accuracy and the suppressor allows me to run 45.2 grains, which is the same load I can run in a 24" barrel but not in an 18". Neither loads show any signs of pressure but the heavier load won't shoot without the can.
You are correct however that the difference in the can or without it is only about 25-50fps with identical loads.
3 grains more powder is adding your velocity not the suppressor. There is nothing magic there and would have clarified it a lot easier.

How many times does someone have to explain that a short barrel magnum will still shoot faster than a short non magnum case? If you want an 18" 300 win why not just buy a 308? Because that person doesn't want a 26" 308 they want an 18" handy rifle. Inefficient yes? Wasted potential? Yep. As long and the person making the rifle understands the limitations of the shorter barrel they are fine. I've had lots of people question short barrel hunting rifles and have the next rifle they build be 18-20". Once they see you can lose a little velocity and gain a whole bunch of handiness they are sold.
 
I built a 18 inch 7mm SAUM with a titanium suppressor, best gun I ever had running 162 grain bullets and RL26 using a magnum primer for the short barrel and a titanium suppressor. Keep in mind that you will NOT like shooting it without a suppressor.....they are loud!!lol
 
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