“Short” Barrels, why not?

[Marbles]

I’m not in the game of wasting money for internet experiments that I find impractical. That said having a short rifle sure is practical, but overall I don’t think caliber of choice should have any bearing on how short you should go based on it being better at being short.

Simply stating what Iv found with the rifles that I have used. Cutting them down regardless of being a caliber that in internet theory losses less velocity, does the same that most other ones do.

I think barrel to barrel speed and SDs make this an exercise in futility without spending more than is reasonable for most. Iv read plenty of articles, and seen it on here plenty. 20-40 fps per inch I believe could happen with about any caliber.


Your 300 win mag example assumes that both cases are making the same velocity. The 300 is creating a lot more energy, it only makes sense that it would lose more in fps, and could be the same proportionally. Both cases losing 10% of velocity is not the same number.



That said I think people need to look at what they need for impact velocity at their given range and choose a realistic and safe to run round. If I want 2800 out of a 18 or 20” rifle I wouldn’t be basing my decision on how much the caliber is supposed to lose per inch or reloading the difference.

Reloading is a whole different conversation. I can make my creedmoor shoot closer to a PRC too. But then I’d have to carry a hammer to open my bolt when it rains.

Data does not have to be yours, others have published data and it can be searched for

No, my example does not assume they are making the same velocity. Data I have seen sugest a 300 win mag looses more than 100 fps per inch on average. Edit, wrong colume read in table, 39 fps. https://rifleshooter.com/2013/12/30...rrel-length-change-velocity-a-16-300-win-mag/

Are you arguing that if someone is selecting a new rifle and chambering for a short barrel they should pay no attention to which chambering will perform the best? Even in percentage terms, the 300 win mag looses more per inch than a 308.

308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28″ to 16.5″)

308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28″ to 16.5″) Introduction Released by Winchester in 1952 (and adopted by NATO in 1954 as the 7.62x51mm NATO), the 308 Wi…

rifleshooter.com

I think I know who just has "internet theory." Such theory almost always starts with a failure to look at available data, then disparaging the data based statements of others.

 

[SOIHUNT]

I’m shooting a 18” 6.5 Prc with a can and it’s my go to rifle. 2943 fps 135 burger Classic Hunters. The attached picture is 200 yards 3 shots and I’ve taken this out to 1000 yards on steel.

 

[Formidilosus]

Data does not have to be yours, others have published data and it can be searched for

No, my example does not assume they are making the same velocity. Data I have seen sugest a 300 win mag looses more than 100 fps per inch on average. https://rifleshooter.com/2013/12/30...rrel-length-change-velocity-a-16-300-win-mag/

Are you arguing that if someone is selecting a new rifle and chambering for a short barrel they should pay no attention to which chambering will perform the best? Even in percentage terms, the 300 win mag looses more per inch than a 308.

308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28″ to 16.5″)

308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28″ to 16.5″) Introduction Released by Winchester in 1952 (and adopted by NATO in 1954 as the 7.62x51mm NATO), the 308 Wi…

rifleshooter.com

I think I know who just has "internet theory." Such theory almost always starts with a failure to look at available data, then disparaging the data based statements of others.

Having used and shot out dozens of 308’s and 300 mags, they all lose the same 20-30fps per inch on max velocity/pressure. If you are a reloader, then keeping the same loads before cut and after doesn’t make sense. When a shorter barrel and a longer barrel have optimum loads for each- they’re all 20-30fps per inch.

 

[Lawnboi]

Data does not have to be yours, others have published data and it can be searched for

No, my example does not assume they are making the same velocity. Data I have seen sugest a 300 win mag looses more than 100 fps per inch on average. https://rifleshooter.com/2013/12/30...rrel-length-change-velocity-a-16-300-win-mag/

Are you arguing that if someone is selecting a new rifle and chambering for a short barrel they should pay no attention to which chambering will perform the best? Even in percentage terms, the 300 win mag looses more per inch than a 308.

308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28″ to 16.5″)

308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28″ to 16.5″) Introduction Released by Winchester in 1952 (and adopted by NATO in 1954 as the 7.62x51mm NATO), the 308 Wi…

rifleshooter.com

I think I know who just has "internet theory." Such theory almost always starts with a failure to look at available data, then disparaging the data based statements of others.

While the above data is interesting and fun to read, I don’t see where your getting 100fps per inch. Here’s a quote from the article summing up the data. “Each reduction in barrel length averaged 39.6 ft/sec in velocity loss”. That lies right in line with what I mentioned above. You also have to look at those SDs. Multiple of the biggest swings have 20+ SDs, I’m betting that 60SD didnt help either. While fun to read and a neat experiment it really says nothing difinitively on how a 300 win mag loses 100fps per inch.

There’s also plenty of threads here on short barreled magnums, such as Ryans 300wsm shorty.

Preform best is a very non specific and general term for a short barreled gun. I dont care how efficient it is if it gets my intended bullet to my target with reasonable precision at the velocity I want impact. If a 308 was something magic then why don’t we see it catching 3006 or 300wsm or 300 win mags when barrel lengths get short? At the end of the day I’d bet that a 16” win mag is going to be faster than a 16” WSM, and that’s going to be faster than a 16” 3006, and that’s going to be faster than a 16”308, and they are all going to be faster than a 16” 300BO. Because more powder means more velocity.

While I don’t have experience with short barreled magnums, or some of the other supposed super efficient short 338 cal builds, I can say from what Iv seen personally, and read on here and elsewhere, within reason…. More powder means more velocity given all else being equal.

I very well may be wrong on this, but I’m not seeing any magic sauce in certain cartridges that makes them more efficient enough in a short barrel to outrun the same bullet with an extra 10 grains of powder burning behind it.

 

[Antares]

It’s not commonly known, but .308s actually gain velocity with shorter barrels.

#M3GA
(Make .308s Great Again)

 

[762 ULTRAMAGA]

While the above data is interesting and fun to read, I don’t see where your getting 100fps per inch. Here’s a quote from the article summing up the data. “Each reduction in barrel length averaged 39.6 ft/sec in velocity loss”. That lies right in line with what I mentioned above. You also have to look at those SDs. Multiple of the biggest swings have 20+ SDs, I’m betting that 60SD didnt help either. While fun to read and a neat experiment it really says nothing difinitively on how a 300 win mag loses 100fps per inch.

There’s also plenty of threads here on short barreled magnums, such as Ryans 300wsm shorty.

Preform best is a very non specific and general term for a short barreled gun. I dont care how efficient it is if it gets my intended bullet to my target with reasonable precision at the velocity I want impact. If a 308 was something magic then why don’t we see it catching 3006 or 300wsm or 300 win mags when barrel lengths get short? At the end of the day I’d bet that a 16” win mag is going to be faster than a 16” WSM, and that’s going to be faster than a 16” 3006, and that’s going to be faster than a 16”308, and they are all going to be faster than a 16” 300BO. Because more powder means more velocity.

While I don’t have experience with short barreled magnums, or some of the other supposed super efficient short 338 cal builds, I can say from what Iv seen personally, and read on here and elsewhere, within reason…. More powder means more velocity given all else being equal.

I very well may be wrong on this, but I’m not seeing any magic sauce in certain cartridges that makes them more efficient enough in a short barrel to outrun the same bullet with an extra 10 grains of powder burning behind it.

This is true
For example I rebarreled my 6.5 saum to 16" and lost exactly 200 fps with the same load using 9" less barrel.
Now I'm running a 144 Berger at 2925, a 26" 6.5 creedmoor couldn't come close to that.
There is one factor to consider with short barrels and maximum velocity, and that's cartridge length.
A short mag has less chamber length and thus more usable barrel compared to a true long action magnum, also the short powder colums seem to torch off more better (just my observation)

No one has argued that a 16 inch 308 is faster than a 16 inch 300 mag. Though, due to loss of dwell time, a 300 mag is likely to loose more velocity if 10 inches is chopped off the barrel as there is less time for more power to burn.

The myth about magnums puking unburned powder out the end of a short barrel has been debunked like 50 years ago. According to ballisticians something like 95% of the powder is burned in the first 4" of a barrel regardless of charge.
What creats more velocity in longer barrels is there's more expansion of the gases through the pressure curve.

 

[BLJ]

Is the increase in muzzle jump significantly greater? Wondering more so about the magnums (7, 300 )?

 

[roosiebull]

Feel free to post data. A larger diameter should give more surface area for gas to act on, meaning less velocity loss cutting down larger calibers. Theory and reality do not always like up though as there are more factors at play, but if that is the case, data will show it to be so.



No one has argued that a 16 inch 308 is faster than a 16 inch 300 mag. Though, due to loss of dwell time, a 300 mag is likely to loose more velocity if 10 inches is chopped off the barrel as there is less time for more power to burn.

I would think the magnums with slower burning powders would lose efficiency at a higher rate than the more traditional cartridges with faster burning powder, correct? That concept seems intuitive to me, but I have not tested any of it and may never…

I would think it’s a bigger deal having a long tube with a big case full of slow burning powder vs a smaller case of fast burning powder…

 

[madcalfe]

I would think the magnums with slower burning powders would lose efficiency at a higher rate than the more traditional cartridges with faster burning powder, correct? That concept seems intuitive to me, but I have not tested any of it and may never…

I would think it’s a bigger deal having a long tube with a big case full of slow burning powder vs a smaller case of fast burning powder…

That’s what I’d think as well, I know my 300wsm with a 20% tube get 97% burn rate according to quick load using h4350
I mean ultimately anything will shoot in a short barrel. I personally thing the saum, wsm, Sherman short, would perform better in a shorter barrel

 

[Marbles]

While the above data is interesting and fun to read, I don’t see where your getting 100fps per inch. Here’s a quote from the article summing up the data. “Each reduction in barrel length averaged 39.6 ft/sec in velocity loss”. That lies right in line with what I mentioned above. You also have to look at those SDs. Multiple of the biggest swings have 20+ SDs, I’m betting that 60SD didnt help either. While fun to read and a neat experiment it really says nothing difinitively on how a 300 win mag loses 100fps per inch.

I misread the table, which is also why I initially asked you to present data rather that presenting my own, confirmation bias and seeing what one wants is very real and wired into our brains. I edited my post to correct it.

As I have already stated a 300 mag is faster than a 308 out of a barrel of the same length, I'm really not sure what point you are trying to make by stating what is already agreed on.

Having used and shot out dozens of 308’s and 300 mags, they all lose the same 20-30fps per inch on max velocity/pressure. If you are a reloader, then keeping the same loads before cut and after doesn’t make sense. When a shorter barrel and a longer barrel have optimum loads for each- they’re all 20-30fps per inch.

Your experience trumps anything I have, so I yield. Out of curiosity, as you have shot both, would you prefer a 16-18 inch 308 or 300 mag?

 

[ZAK13]

I've been pretty happy over the years shooting my 22" barreled rifles ,(.243, .270 & 30-06), have gotten good results with all of them. Just recently purchased a Ruger American Predator in .308 and an 18" tube. Although I haven't checked velocities yet, a very handy, accurate rifle. I liked the balance of it. The more I shoot it, the more it appeals to me. It might just become my go to very soon. As a side note, I don't shoot much past 300 yards at game, actually for all the years of hunting I've done, my furthest shot to date was just under 400 yards. Most of my shots are 200 or less.

 

[Formidilosus]

Your experience trumps anything I have, so I yield. Out of curiosity, as you have shot both, would you prefer a 16-18 inch 308 or 300 mag?

I’m not trying to trump anything.

Either, or neither, depending. I do not care about the container that holds my fuel. It’s just “x” bullet, at “x” yards for terminal effects, and maybe at “x” length- whatever fuel container that takes is fine to me. I have/had 308’s down to 13.5” and 300 mags down to 17”- they were all fine for the tasks.

Having said that; for true short barrels, terminal, effects, and hit rates- there are much better options than 30cal anything.

 

[Marbles]

I’m not trying to trump anything.

Either, or neither, depending. I do not care about the container that holds my fuel. It’s just “x” bullet, at “x” yards for terminal effects, and maybe at “x” length- whatever fuel container that takes is fine to me. I have/had 308’s down to 13.5” and 300 mags down to 17”- they were all fine for the tasks.

Having said that; for true short barrels, terminal, effects, and hit rates- there are much better options than 30cal anything.

I feel there is a little over simplification in that answer. Different containers have characteristics beyond just velocity. Even if cost and action size are ignored, how easy it is to mitigate the effects of recoil and muzzle blast influences a shooters ability to use the terminal effects. This is true whether mitigation is achieved through skill or through equipment design.

I will also acknowledge that the question I asked lends itself to overly simple answers.

 

[Formidilosus]

I feel there is a little over simplification in that answer. Different containers have characteristics beyond just velocity. Even if cost and action size are ignored, how easy it is to mitigate the effects of recoil and muzzle blast influences a shooters ability to use the terminal effects. This is true whether mitigation is achieved through skill or through equipment design.

I will also acknowledge that the question I asked lends itself to overly simple answers.

I’m not sure it is overly simplistic. I don’t find cartridges to be magical or generally unique. Some are generally very forgiving and have known loads that shoot well in all- 6mm BR derivatives, 6XC, 6.5Cm, etc., but I haven’t seen any in a properly constructed rifle that didn’t shoot fine.

As for recoil and muzzle blast- exactly why I wouldn’t use a 30cal for really short barrels usually. If I wanted a 600 yard deer/elk rifle with a 16-18” barrel it won’t be a 30cal anything, and probably not a 7mm. 6.5, 6mm, and .224’s can all get the required velocity with good bullets for 600 yards with much less recoil and blast, and they should all be suppressed.

 

[CoStick]

Is there a blast difference between 6.5 CM and PRC in regards to suppressed performance?

 

[Formidilosus]

Is there a blast difference between 6.5 CM and PRC in regards to suppressed performance?

Yes. Larger powder charges in the same can, and or shorter barrels increase both sound level and blast. However, wether or not someone can tell between them depends, and either are massively better than unsuppressed.

 

[CoStick]

Yes. Larger powder charges in the same can, and or shorter barrels increase both sound level and blast. However, wether or not someone can tell between them depends, and either are massively better than unsuppressed.

Have been planning on suppressing my .270 win, but the idea of 6.5 prc is appealing if there is a better benefit.

 

[Formidilosus]

Have been planning on suppressing my .270 win, but the idea of 6.5 prc is appealing if there is a better benefit.

They both will suppress as well as the other.

 

[clperry]

Everything in the safe is 20 or less now. Since going suppressed, I see no reason to carry long barrels.


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[displacedtexan]

I'm dropping the rifle I'm building for my all purpose gun off at the gunsmith tomorrow.

Going to 18" (6.5cm)