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Posted: 7/17/2014 3:13:14 PM EDT
[#1]
Nope. My Maten has a 16" barrel, and it's done everything I've wanted with it.
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Posted: 7/17/2014 3:28:19 PM EDT
[#2]
No. Best all around practical length for handling and shooting.
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Posted: 7/17/2014 3:55:44 PM EDT
[#3]
OP, unless you're going some seriously long range shooting (like 700+ yards) a 16" barrel will do all you need.
At the same time, I wouldn't let weight discourage you from going with a longer barrel if that's what you want. I say that because AR 308's are heavy - period. It isn't a rifle you're gonna want to run and gun with anyway. That's just my .02 though. |
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Posted: 7/17/2014 5:30:59 PM EDT
[#4]
Unless you plan on shooting extremely long distance, the 16" will be fine. It will still work at very long distances, you will just have more bullet drop. I have no regrets on getting a 16" 308 barrel, plus I wanted to keep the suppressor weight as close in as possible.
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Posted: 7/17/2014 6:05:26 PM EDT
[#5]
IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches...
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Posted: 7/17/2014 7:38:22 PM EDT
[#6]
I recently built a LR308 with an 18 inch barrel. I now wish I had used a 16 inch.
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Posted: 7/17/2014 10:00:27 PM EDT
[#7]
Now, what if we switch the topic up a bit and say we are shooting a 260 Rem, or Creedmoor instead of 308. It seems that I do not see 6.5 cal barrels any shorter than 20 inches, yet 6.5 grendel barrels can be found down to pistol length. I shoot a 6.5 grendel in 18 inch, and really like it, but if I could get a 16" 260, and still get 2600 FPS with a 139 grain bullet I would take it. I know it is asking quite a bit, and the 260 does not like to be pushed hard so I may be asking too much.
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Posted: 7/18/2014 3:21:35 AM EDT
[#8]
I'm a 20" & 24" fan for 308.
The day I need a 16" pipe is when there will be 5.56, 6.8 & 458 SOCOM brass on the ground. I might be able to tolerate an 18" in 308... Nope, nope, just got a dose of the willies. Nope, 20/24/26 inches only. |
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Posted: 7/22/2014 4:57:17 AM EDT
[#9]
16 inch is gtg.
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Posted: 7/22/2014 11:51:21 AM EDT
[#10]
You want a carbine or do you want a long range rifle?
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Posted: 7/22/2014 1:53:05 PM EDT
[#11]
is anyone shooting a 308 with a less than 16" barrel?
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Posted: 7/23/2014 9:51:17 AM EDT
[#12]
I think 16.5" is the perfect barrel length for a .308 AR
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Posted: 7/23/2014 10:00:40 AM EDT
[#13]
Quote HistoryQuoted:
is anyone shooting a 308 with a less than 16" barrel? I will be in however many months it takes for my form 1 to get approved. Going to 12.5" It'll be a run and gun suppressed hog hunter. It'll be in and out of vehicles, side-by-sides, helis, and running through thick brush. |
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Posted: 7/23/2014 1:25:33 PM EDT
[#14]
Quote HistoryQuoted:
I'm a 20" & 24" fan for 308. The day I need a 16" pipe is when there will be 5.56, 6.8 & 458 SOCOM brass on the ground. I might be able to tolerate an 18" in 308... Nope, nope, just got a dose of the willies. Nope, 20/24/26 inches only. I'm with you, for a my AR-10 I like the 20. If I need a short barrel, I have a 300 whisper in m4 config. |
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Posted: 7/23/2014 1:45:31 PM EDT
[#15]
Quote HistoryQuoted:
I'm a 20" & 24" fan for 308. The day I need a 16" pipe is when there will be 5.56, 6.8 & 458 SOCOM brass on the ground. I might be able to tolerate an 18" in 308... Nope, nope, just got a dose of the willies. Nope, 20/24/26 inches only. How does it make you feel to know I use a 14.5"??? |
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Posted: 7/23/2014 3:49:31 PM EDT
[#16]
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is anyone shooting a 308 with a less than 16" barrel? I shoot a 14.5 and I want to go shorter. I am building either a 10.5 or 12.5 here in the next few months. I also have a couple with 16" barrels and one with an 18". |
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Posted: 7/23/2014 4:10:03 PM EDT
[#17]
I'm with Dave and Mark. My 308 AR has a 22 inch barrel. For something smaller/lighter than 308 but more powerful than 5.56 I have a 6.8 which was designed from the ground up to work with short barrels.
One side thought for you short barreled 308 fans. Most factory ammo is optimized for longer barrels. Think about the available factory barrel lengths of most 308 caliber hunting rifles like the Remington 700. They are almost all longer than 20 inches with 22 and 24 inches being the most popular. Thus, if you want to get the most out of a shorter barreled 308, consider reloading. In the end there is plenty of reasons to own short and long barreled 308s. Just depends on your use case. |
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Posted: 7/23/2014 5:38:17 PM EDT
[#18]
Quote HistoryQuoted:
is anyone shooting a 308 with a less than 16" barrel? yes 
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Posted: 7/23/2014 6:56:31 PM EDT
[#19]
Yep. http://www.kakindustry.com/lr-308-parts/lr308-kak-1050-carbine-7-62nato
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Posted: 7/23/2014 7:03:02 PM EDT
[#20]
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Thus, if you want to get the most out of a shorter barreled 308, consider reloading. . Or, order bulk. http://www.ammunitiondepot.com/7-62x51-XM80-149-Grain-FMJ-Bulk-Ammo-p/adxm80pac350.htm . Have seen them sell 500 round packages too as that was my last order. |
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Posted: 7/23/2014 7:53:08 PM EDT
[#21]
Quote HistoryQuoted:
Or, order bulk. http://www.ammunitiondepot.com/7-62x51-XM80-149-Grain-FMJ-Bulk-Ammo-p/adxm80pac350.htm . Have seen them sell 500 round packages too as that was my last order. Quote HistoryQuoted:
Quoted:
Thus, if you want to get the most out of a shorter barreled 308, consider reloading. . Or, order bulk. http://www.ammunitiondepot.com/7-62x51-XM80-149-Grain-FMJ-Bulk-Ammo-p/adxm80pac350.htm . Have seen them sell 500 round packages too as that was my last order. m80 ball is not really idea for short barrels , good plinking ammo though. i believe Silver78 meant a load like mk319 mod 0 , it's the sost round optimized for short barrels. |
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Posted: 7/23/2014 8:22:16 PM EDT
[#22]
Quote HistoryQuote HistoryQuoted:
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is anyone shooting a 308 with a less than 16" barrel? yes
http://img.photobucket.com/albums/v619/1iviper/IMG_0898_zps34867e74.jpg What color is that Cerakote? Looks nice! |
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Posted: 7/23/2014 11:12:49 PM EDT
[#23]
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What color is that Cerakote? Looks nice! Quote HistoryQuoted:
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is anyone shooting a 308 with a less than 16" barrel? yes
http://img.photobucket.com/albums/v619/1iviper/IMG_0898_zps34867e74.jpg What color is that Cerakote? Looks nice! patriot brown |
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Posted: 7/24/2014 5:34:05 PM EDT
[#24]
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How does it make you feel to know I use a 14.5"??? Quote HistoryQuoted:
Quoted:
I'm a 20" & 24" fan for 308. The day I need a 16" pipe is when there will be 5.56, 6.8 & 458 SOCOM brass on the ground. I might be able to tolerate an 18" in 308... Nope, nope, just got a dose of the willies. Nope, 20/24/26 inches only. How does it make you feel to know I use a 14.5"??? Doesn't make me feel a da-da-damn thing. I just figure that you can't afford a sub-16": A) 6.8x43mm B) 5.56mm C) 458 SOCOM
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Posted: 7/24/2014 6:37:17 PM EDT
[#25]
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I will be in however many months it takes for my form 1 to get approved. Going to 12.5" It'll be a run and gun suppressed hog hunter. It'll be in and out of vehicles, side-by-sides, helis, and running through thick brush. Quote HistoryQuoted:
Quoted:
is anyone shooting a 308 with a less than 16" barrel? I will be in however many months it takes for my form 1 to get approved. Going to 12.5" It'll be a run and gun suppressed hog hunter. It'll be in and out of vehicles, side-by-sides, helis, and running through thick brush. Same |
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Posted: 7/28/2014 6:19:18 AM EDT
[#26]
My 16 " Rock River will hold the 10/X ring at 600 yards. It will also hit a human silhouette most shots at 1000.
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Posted: 7/29/2014 1:39:56 PM EDT
[#27]
I have at least one 16", 18", 20", and 22".
18 is by far my favorite. If I were to go shorter, it would be 12 and only shot with a can attached. Blast/noise from an 18 stinks without a can on. And 16 is a lot worse. If you're only using it on the range and always have double ear pro, that's one thing. If you really use it, it's not a lot of fun. |
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Posted: 8/1/2014 10:08:21 AM EDT
[#28]
Quote HistoryQuoted:
How does it make you feel to know I use a 14.5"??? Quote HistoryQuoted:
Quoted:
I'm a 20" & 24" fan for 308. The day I need a 16" pipe is when there will be 5.56, 6.8 & 458 SOCOM brass on the ground. I might be able to tolerate an 18" in 308... Nope, nope, just got a dose of the willies. Nope, 20/24/26 inches only. How does it make you feel to know I use a 14.5"??? Your gun, your way.... |
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Posted: 8/2/2014 6:24:03 AM EDT
[#29]
Quote HistoryQuoted:
IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches... That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). |
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Posted: 8/2/2014 7:43:42 AM EDT
[#30]
Quote HistoryQuoted:
That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). Quote HistoryQuoted:
Quoted:
IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches... That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). 
EDIT Not no, BUTT!!! hell no. Even that was not enough, technically. So, I must add: 
And it doesn't take the da-da-damn integral f(x) by separation of parts to figure it out. ________________________________ BTW, Ghostface, how ya' doing, sir? Generically speaking... since you were.
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Posted: 8/2/2014 9:20:38 AM EDT
[#31]
 my 12.5 308..
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Posted: 8/2/2014 10:13:07 AM EDT
[#32]
try a 7.5
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Posted: 8/2/2014 11:44:58 AM EDT
[#33]
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http://assets.diylol.com/hfs/c24/551/19d/resized/sopa-gtfo-meme-generator-leave-the-internet-alone-292982.jpg EDIT Not no, BUTT!!! hell no. Even that was not enough, technically. So, I must add: http://store.thescrib.com/wp-content/uploads/2013/02/bazinga-kelly-green-women.jpg And it doesn't take the da-da-damn integral f(x) by separation of parts to figure it out. ________________________________ BTW, Ghostface, how ya' doing, sir? Generically speaking... since you were.
Quote HistoryQuoted:
Quoted:
Quoted:
IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches... That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). http://assets.diylol.com/hfs/c24/551/19d/resized/sopa-gtfo-meme-generator-leave-the-internet-alone-292982.jpg EDIT Not no, BUTT!!! hell no. Even that was not enough, technically. So, I must add: http://store.thescrib.com/wp-content/uploads/2013/02/bazinga-kelly-green-women.jpg And it doesn't take the da-da-damn integral f(x) by separation of parts to figure it out. ________________________________ BTW, Ghostface, how ya' doing, sir? Generically speaking... since you were.
wut |
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Posted: 8/2/2014 6:19:35 PM EDT
[#34]
Quote HistoryQuoted:
wut Quote HistoryQuoted:
Quoted:
Quoted:
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IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches... That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). http://assets.diylol.com/hfs/c24/551/19d/resized/sopa-gtfo-meme-generator-leave-the-internet-alone-292982.jpg EDIT Not no, BUTT!!! hell no. Even that was not enough, technically. So, I must add: http://store.thescrib.com/wp-content/uploads/2013/02/bazinga-kelly-green-women.jpg And it doesn't take the da-da-damn integral f(x) by separation of parts to figure it out. ________________________________ BTW, Ghostface, how ya' doing, sir? Generically speaking... since you were.
wut Eggxactly!!! Do you even "AREA UNDER THE CURVE", bro? 14er. Technically. |
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Posted: 8/2/2014 6:39:49 PM EDT
[#35]
Quote HistoryQuoted:
Eggxactly!!! Do you even "AREA UNDER THE CURVE", bro? 14er. Technically. Quote HistoryQuoted:
Quoted:
Quoted:
Quoted:
Quoted:
IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches... That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). http://assets.diylol.com/hfs/c24/551/19d/resized/sopa-gtfo-meme-generator-leave-the-internet-alone-292982.jpg EDIT Not no, BUTT!!! hell no. Even that was not enough, technically. So, I must add: http://store.thescrib.com/wp-content/uploads/2013/02/bazinga-kelly-green-women.jpg And it doesn't take the da-da-damn integral f(x) by separation of parts to figure it out. ________________________________ BTW, Ghostface, how ya' doing, sir? Generically speaking... since you were.
wut Eggxactly!!! Do you even "AREA UNDER THE CURVE", bro? 14er. Technically. That was du-du-dumb... |
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Posted: 8/3/2014 2:32:18 AM EDT
[#36]
Quote HistoryQuoted:
Eggxactly!!! Do you even "AREA UNDER THE CURVE", bro? 14er. Technically. Quote HistoryQuoted:
Quoted:
Quoted:
Quoted:
Quoted:
IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches... That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). http://assets.diylol.com/hfs/c24/551/19d/resized/sopa-gtfo-meme-generator-leave-the-internet-alone-292982.jpg EDIT Not no, BUTT!!! hell no. Even that was not enough, technically. So, I must add: http://store.thescrib.com/wp-content/uploads/2013/02/bazinga-kelly-green-women.jpg And it doesn't take the da-da-damn integral f(x) by separation of parts to figure it out. ________________________________ BTW, Ghostface, how ya' doing, sir? Generically speaking... since you were.
wut Eggxactly!!! Do you even "AREA UNDER THE CURVE", bro? 14er. Technically. Do you even technical forum, bro? I avoid GD so I don't have to see regurgitated meme BS and nonsensical rambling. I shouldn't have to suffer through it here (1st world problems). If you are criticizing my 40" figure, I based it on no technical data (hence the 'probably' and 'generically'). I remember seeing someone create a computer model showing the pressure equalizing at 44" in barrel length, I have personally never seen a .308 win barrel beyond 34". I know it would depend on a lot of factors since there are a lot of things that could be done to decrease the drag and parasitic loss from the bullet alone (the fastest rounds are sabot rounds after all).. regardless, powder still does not burn down the barrel (at least in the sense that was implied), that was the point of my reply. An 18" will not "complete powder burn" more than a 16". It is not a valid reason to "regret a shorter barrel" (if you recall the OP). If you want to criticize me, by all means, do so, but enlighten me. That is why I am here. I do not speak gerbil. Images of Chris Crocker and t-shirt advertisements just show me that you would rather search the internet for 5 minutes for idiotic images to add to your post rather than actually saying something of benefit or use to anyone, not to mention the incoherent text and lack of any structure.. a post not worth much more than a raised eyebrow and a "wut?" ...You could even go as far as to answering the OP, with some reasoning, technical data, da-da-damn integral f(x).. I would be happy to read it. Thank you. |
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Posted: 8/3/2014 7:56:04 PM EDT
[#37]
Quote HistoryQuoted:
Eggxactly!!! Do you even "AREA UNDER THE CURVE", bro? 14er. Technically. Quote HistoryQuoted:
Quoted:
Quoted:
Quoted:
Quoted:
IMO 18 inches is the most versatile length. It's compact enough to be a carbine and yet long enough to have complete powder burn. I lost only 55 FPS cutting my barrel down from 22 inches to 18. I shoot in excess of 700 yards so I will take that extra two inches... That is myth/misconception. The powder will be burned off as much as it is going to be in either a 16" or 18". A slow burn powder will only last about 3-4" down the barrel before it is consumed (at least 97%+ consumed, 100% is not plausible).. the pressure from expanded gases is what pushes the bullet.. and peak pressure is established once the bullet leaves the casing, it does not continue to climb like some also think.. For .308 Win you would probably need a 40"+ barrel for that pressure mass to diminish to the point it would stop accelerating the bullet (generically speaking). http://assets.diylol.com/hfs/c24/551/19d/resized/sopa-gtfo-meme-generator-leave-the-internet-alone-292982.jpg EDIT Not no, BUTT!!! hell no. Even that was not enough, technically. So, I must add: http://store.thescrib.com/wp-content/uploads/2013/02/bazinga-kelly-green-women.jpg And it doesn't take the da-da-damn integral f(x) by separation of parts to figure it out. ________________________________ BTW, Ghostface, how ya' doing, sir? Generically speaking... since you were.
wut Eggxactly!!! Do you even "AREA UNDER THE CURVE", bro? 14er. Technically. I do, and you apparently do not know enough Newtonian physics to understand it is not a derivative of f(x). Yes barrel length is a factor of speed past 4" in a barrel. Understand that internal ballistics formulas are different than exterior ballistics due to the pressure created by the propellant, as well as the bore. You can calculate what the difference in barrel lengths will do if you know certain parts of the equation. y = force; x = position; b = length of gun; s = constant, and plug into the Le Duc formula. v(x) =rx/s + x. I could write it all out for you, but I would like to see you add to this discussion rather than go all neanderthal with pictures of ugly chicks. Gota have the tata's. 
Knowing what I know I compromised with an 18" barrel, but a 16 will get it done. Anything over 20 inch and you only get very marginal gains. |
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Posted: 8/9/2014 3:22:56 AM EDT
[#38]
Quote HistoryQuoted:
I do, and you apparently do not know enough Newtonian physics to understand it is not a derivative of f(x). Yes barrel length is a factor of speed past 4" in a barrel. Understand that internal ballistics formulas are different than exterior ballistics due to the pressure created by the propellant, as well as the bore. You can calculate what the difference in barrel lengths will do if you know certain parts of the equation. y = force; x = position; b = length of gun; s = constant, and plug into the Le Duc formula. v(x) =rx/s + x. I could write it all out for you, but I would like to see you add to this discussion rather than go all neanderthal with pictures of ugly chicks. Gota have the tata's.
Knowing what I know I compromised with an 18" barrel, but a 16 will get it done. Anything over 20 inch and you only get very marginal gains. Interesting stuff. That Le Duc model seems to be one of the oldest (pub. 1905), and seems pretty outdated by some of the others I have seen after some quick internet searches. Most do not take in to account losses, at least not effectively (which would be difficult to do, considering differences in rifling twist, rifling cut, geometry, surface finish, effects of heat, fouling and so on.. they are just empirical models after all). In some boredom I fired up excel and used a model I found on the internet by Homer Powley. I used data from the M24 with M118LR loads. (it was claimed that results matched up to a .223 rem barrel within 5 fps going all the way down to 3") The way this model works, I would not have any faith in the velocities beyond the original 24" barrel length, but that is expected. I should try and find that .308 max barrel length model I seen a long while ago. 
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Posted: 8/9/2014 3:50:52 PM EDT
[#39]
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Interesting stuff. That Le Duc model seems to be one of the oldest (pub. 1905), and seems pretty outdated by some of the others I have seen after some quick internet searches. Most do not take in to account losses, at least not effectively (which would be difficult to do, considering differences in rifling twist, rifling cut, geometry, surface finish, effects of heat, fouling and so on.. they are just empirical models after all). In some boredom I fired up excel and used a model I found on the internet by Homer Powley. I used data from the M24 with M118LR loads. (it was claimed that results matched up to a .223 rem barrel within 5 fps going all the way down to 3") The way this model works, I would not have any faith in the velocities beyond the original 24" barrel length, but that is expected. I should try and find that .308 max barrel length model I seen a long while ago. http://i.imgur.com/uPwFHl3.jpg Quote HistoryQuoted:
Quoted:
I do, and you apparently do not know enough Newtonian physics to understand it is not a derivative of f(x). Yes barrel length is a factor of speed past 4" in a barrel. Understand that internal ballistics formulas are different than exterior ballistics due to the pressure created by the propellant, as well as the bore. You can calculate what the difference in barrel lengths will do if you know certain parts of the equation. y = force; x = position; b = length of gun; s = constant, and plug into the Le Duc formula. v(x) =rx/s + x. I could write it all out for you, but I would like to see you add to this discussion rather than go all neanderthal with pictures of ugly chicks. Gota have the tata's.
Knowing what I know I compromised with an 18" barrel, but a 16 will get it done. Anything over 20 inch and you only get very marginal gains. Interesting stuff. That Le Duc model seems to be one of the oldest (pub. 1905), and seems pretty outdated by some of the others I have seen after some quick internet searches. Most do not take in to account losses, at least not effectively (which would be difficult to do, considering differences in rifling twist, rifling cut, geometry, surface finish, effects of heat, fouling and so on.. they are just empirical models after all). In some boredom I fired up excel and used a model I found on the internet by Homer Powley. I used data from the M24 with M118LR loads. (it was claimed that results matched up to a .223 rem barrel within 5 fps going all the way down to 3") The way this model works, I would not have any faith in the velocities beyond the original 24" barrel length, but that is expected. I should try and find that .308 max barrel length model I seen a long while ago. http://i.imgur.com/uPwFHl3.jpg De luc is old, but easy for someone who is not well versed in mathematics to follow. Even by the Homer Powley model you so kindly entered into Excel so we can get a visual shows the difference between 18" barrel will only give you a gain of 100 FPS going to 24". But, as you can see there is enough difference between 24" and 16" that the drop in FPS is more than double for that last two inches vs the difference in loss in the first 6 inches between 24" and 18". If you will never shoot past 600 yards it wont make a difference between 24, and 16 inches, but you have to take in to consideration other things besides the math. A 24" barrel in the woods is not fun, and I have yet to hear about a 1000 yard 308 deer harvest. |
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