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Post by omnivorous on Dec 4, 2014 18:42:05 GMT -5
So, even though I've got a 16" mid-length, PSA barreled upper on the the way, I'm still wonder what the true advantages between the 16" barrel vs 18 or 20" barrels. The two big infantry forces of the US military (Army & Marines), have seemed to be solidifying in with their choices, because of their differing doctrines: the Army being more focuses on mounted patrols, thus a shorter and adjustable weapon being required, and the Marines being more focused on foot patrols, thus a longer weapon's "disadvantages" aren't. You squeeze-out a couple hundred meters per second with the longer barrel, but you have have to deal with the extra weight. You get less weight, but with a more harsh(-ish) cycle. Hell, I'll probably get both, eventually, but is a +16" barreled AR going to be more than a just a SAM-R, SPR, DMR, whatever, type rifle? Not to mention VLTOR, and their A5 recoil system...
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Post by hudson5969 on Dec 5, 2014 1:01:08 GMT -5
When I built my AR,I built a 20" for a few reasons, mainly it was for reliability and terminal effect.
Reliability is best with the rifle length system on a 20" barrel. An 18" is good, but the longer dwell time of the 20 does help. You don't hear much bitching about A2/A3s and A4s malf-ing, like you do with the M4.
Next is terminal effect. The terminal effects that make the 5.56rather legendary as a killer are dependent on its fragmentation, which is dependent upon impact velocity. M193 will fragment reliably to roughly 200m from a 20" barrel, about 110m from a 14.5. M855 will frag out to about 160m from a 20" and about 60m from a 14.5. The 16" would be slightly better than the 14.5. Event he newer bullet designs will expand or fragment to a greater range because of the higher muzzle velocity. IMO, you give up a lot for the shorter barrel.
If you use an A5 stock, you can collapse it down so the weapon isn't much longer than an 18.5" shotgun, which most find to be a fairly svelte gun.
If you are going to do a lot of close-in urban door-kicking, then the shorter weapon will have a definite advantage for you. But if it's mostly outdoors, I didn't find the 20" to be burdensome. I would definitely recommend keeping the front end lighter though. Get a government profile barrel, put MOE furniture on it and a light and a sling, mount your optic to the receiver. You don't want to add a lot of metal to the front end.
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Post by panzer0170 on Dec 5, 2014 6:08:50 GMT -5
Necessary post saying get a bullpup and put a 20" barrel on it. Someone has to, may as well be me.
It all depends on what YOU are doing with it, really. Do you live in a tower block that's full of drug dealers, or in the wilderness with a clear view for 5-600m all round?
The main, key consideration if it's not just a target/comp gun really is 'will it reliably stop XYZ at the distances it will be with you to use?' If it won't, I would have to say you want a longer barrel, if that's what's going to achieve the stopping power you wanted.
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Post by waffenmacht on Dec 5, 2014 7:50:50 GMT -5
In my opinion, it doesn't really matter at all when we are talking about 16"-20" in a 5.56 combat rifle.
Of the guys I train with, no one runs anything longer then 16" unless it is in a "precision" or DMR role.
Even the Marines in my group have ditched the nostalgic 20" for 16" barrels.
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Post by hudson5969 on Dec 5, 2014 9:27:52 GMT -5
Panzer, closest you could get as far as I know is an 18" Tavor, which I confess, I have been drooling over as of late.
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Post by UnforseenWeather on Dec 5, 2014 9:43:59 GMT -5
I'm a fan of longer barrels personally. The extra 4" (from 16 to 20) can't weigh that much more.
I think the 18" barreled guns are the perfect compromise.
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Post by panzer0170 on Dec 5, 2014 9:59:10 GMT -5
My thoughts are, essentially, this;
If we could, we would all carry a weapon that would kill anything we needed it to kill.
Other things affect the fact we can't do this; Size, Weight, etc.
Therefore, the primary factor in choosing a weapon should be it's ability to stop target X, be it human, bear, or elephant.
A lot of the rest actually boils down to convenience. If you live in some sort of arid area, and you're not working in enclosed vehicles... what advantage does having a shorter barrel really have?
The old argument against bullups and left hand firing - I know of people who have gone through several tours with an SA80 in both Iraq (urban setting) AND Afghan (mixtures) and have no complaints of this whole firing left handed business. It seems to be one of those excuses that is trotted out but I think this is only a REAL problem if your work is pure door-to-door room-to-room work, and even then... not everyone is going RIGHT round every entrance.... ( I know I've gone off topic, but it's another example of something that people will argue till their blue in their teeth for. If I were getting a NEW weapon I'd consider starting at the longest practical length and cutting down as far as your intended environment needs, even as far as a 'pistol' AR, if it's going to be something you need to store in the back of a vehicle in a small space, or something you want to be able to carry without it being an issue.
Essentially, I'd start with as much power and bulk as you need to get the job done, and only trim back where you NEED to.
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Post by panzer0170 on Dec 5, 2014 10:01:25 GMT -5
Panzer, closest you could get as far as I know is an 18" Tavor, which I confess, I have been drooling over as of late. Well, the SA80 is 20" barrel, but they're not for public consumption  But yes. There is the RFB which comes in target barrels up to something crazy like 26" - If they were proven and reliable, I would like this firearm. But from what I see.... Not so much. |
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Post by hudson5969 on Dec 5, 2014 11:25:27 GMT -5
SA80, from what I heard is no peach in terms of reliability, either, nor is the AUG.
The FS2000 looked promising and I heard great things about it, so naturally FN stopped production to concentrate on the M4 contract......
IMO the Tavor looks like the only good bullpup game in town.
You give up a little in terminal effect with 18", but I'd not lose sleep over it, and it's a long-stroke piston, so any reliability of the 20" over 18" in a direct impingement system doesn't apply here.
The $1750 street price is kinda sucky, but I'm still wanting one. Damn you and your bullpups!
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Post by UnforseenWeather on Dec 5, 2014 11:38:31 GMT -5
There were a few other bullpup options at SHOT this year that I saw video of. Hopefully they're not vaporware - Kel Tec has another version coming out, and another company is working on one as well.
I know they'd be a couple years off (so they get a chance to iron out any wrinkles) but hopefully options will exist.
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Post by panzer0170 on Dec 5, 2014 12:35:17 GMT -5
SA80, from what I heard is no peach in terms of reliability, either, nor is the AUG. The FS2000 looked promising and I heard great things about it, so naturally FN stopped production to concentrate on the M4 contract...... IMO the Tavor looks like the only good bullpup game in town. You give up a little in terminal effect with 18", but I'd not lose sleep over it, and it's a long-stroke piston, so any reliability of the 20" over 18" in a direct impingement system doesn't apply here. The $1750 street price is kinda sucky, but I'm still wanting one. Damn you and your bullpups! SA80A2 is fine. It's the same as saying M16's are crap because in vietnam they were crap. They were crap in the first gulf and HK has fixed that shit, for a tidy sum. AUG bothers me that one of the IA drills for a stoppage is to remove the fucking barrel, and aussie infanteers carry spare barrels for that same reason. I would definitely take a Tavor, though  |
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Post by Erick on Dec 5, 2014 16:03:41 GMT -5
I believe the 16 inch barrel to be a perfectly balanced approach and hits the sweet spot for me.
it gives up very little in terminal velocity vs the 20 inch but gains a tremendous 4 inches in improved handiness.
True SBRs, such as 11.5 and even 14.5, OTOH suffer a significant performance penalty that the 16 inch largely avoids.
It seems going around 15 inch barrel lenght is a cliff that affect performance.
With a mid-lenght gas there is also no reliability disadvantage vs the 20 inch w/ rifle lenght.
Incidentally the AK series is also at 16 inches....
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Post by omnivorous on Dec 6, 2014 1:42:19 GMT -5
I've heard the terminal effect argument, but since I'm not working for the military, I can use hollow point rounds, or at least soft noses; not much to worry about "ice-picking", unless its a really close in shoot. I'm all for getting on the bullpup bandwagon, with a Tavor, but a Tavor is like twice-plus the cost of my AR.  The Tavor, I'm strongly debating as my next eventual purchase, as a "truck gun". I live in an area which is a mix of urban and rural, and then urban, and then rural again, terrain types. So, something which will work better across a spectrum of fire lanes is more ideal for me. waffenmacht, are the reasons the Marines in your group went with the 16" barrels over the 20s they're used to, solely for reduced weight and whatnot? And Erick, a 5.56 AK is definitely in my future, at some point.  |
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Post by panzer0170 on Dec 6, 2014 7:59:54 GMT -5
The cost does make me baulk a little; Rifle & ACOG scope and you're upwards of $4k already.  |
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Post by UnforseenWeather on Dec 6, 2014 12:35:33 GMT -5
Desert Tech is the name of the new company making semi-auto bullpups. It just came to me.
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But yes. There is the RFB which comes in target barrels up to something crazy like 26" - If they were proven and reliable, I would like this firearm. But from what I see.... Not so much.
The Tavor, I'm strongly debating as my next eventual purchase, as a "truck gun". I live in an area which is a mix of urban and rural, and then urban, and then rural again, terrain types. So, something which will work better across a spectrum of fire lanes is more ideal for me.
