Difference between m4 and m16

[m102404]

Yes, of course...sight radius is negated by optics...the guy didn't specify accessories, just wanted to know the difference between the two rifles. Iron sights do come into play when optics fail, batteries die, WWII games, etc...

Hmm...I would agree with the short, fat barrel thing for major caliber (and I guess rimfires as well..) centerfire rounds. I used to shoot PPC with a 20" full diameter barrel. 22-26" standard taper seemed just about right for .308 out to 800...32" was superb at 1000 (but hard to fit in a case).

I'm not convinced that barrel harmonics play such a role with airsoft rifles.

Pneumatic rifles with heavy barrels tend to derive their benefit from the added front weight that acts to stabilize the system and retard movement errors that come from holding the rifle. Not too many Anchutz rifles out there with 1" zero taper barrels...and if that's what was demanded by the guys who shot that type of stuff, it'd be "fat & short" on their production rifles.

The basic premise with the OP question was "all things being equal"...and to that tune I figured that at the muzzle both rifles shot the same velocity. With the longer barrel (assuming bore diameters to be the same)...I'm still convinced that the longer barrel will result in a smaller target group at any distance compared to a shorter barrel.

Is there a lower end to your reasoning (i.e. how short can a barrel be)? If an M4 and an MP5 both shoot 300fps at the muzzle....and if all their parts are comparable...just the inner barrels are different...would the M4 not shoot more accurately?

Innately, does a 3.5" detonics GBB shoot more accurately than a 5" 1911 GBB?

Excuse my ignorance...I know what lock time is, but what's "dwell time"? Honestly not familiar with the term.

I'm also completely ignorant of painball guns...is there backspin imparted on the paintball by some physical mechanism in the paintball gun?

Maybe dumb it down a bit for me or put it in layman's terms...I'm ok with being wrong.

[tunabreath]

Yes, harmonics are probably not a major issue for airsoft but stiffness is still very desirable to control general flex, which is more of a concern for airsoft than anything else because of the relatively poor quality of materials and construction. I mean flex as far as handling the weapon goes, especially leaning against cover and barrel mounted bipods, etc. Suffice to say, shorter weapons with fewer bits sticking out tend to be more durable, and will hold their point of impact better when bumped around. This is more in line with accuracy rather than consistency/grouping. Having a one piece barrel very rigidly attached to your receiver definitely helps. (not that the inner can be help very rigidly attached anyways because it has to float in the hopup chamber).

Either way, I doubt shorter barrels are actually any more accurate than longer barrels in airsoft, I just don't think that longer barrels any more accurate either. People seem to put more stock into the idea of longer=better than it ever actually seems to be, especially on the field.

There probably is a shorter limit, but it is likely much shorter than common anyways. The hop up is so much more important than the actual length of the barrel. Look at the VSR10 GSpec - 330mm inner. Look at the TM Mk23 - just 200mm, but still regularly out shooting AEGs. It's because they have such a stable hop up chamber.

Dwell time is the period where the projectile is still traveling down the barrel after having been fired. It's obviously a lot more significant with slow moving projectiles like paintballs and airsoft BBs. The longer the dwell time, the more opportunity for shooter movement to influence the shot, just like lock time.

Regarding paintball, systems exist which provide back spin but I believe the majority do not. It is fairly analogous to airsoft as far as spherical projectile, smooth bore goes though.


I guess what it comes down to is that there are so many MORE effective things you can do to improve accuracy (ammo is probably most important, second is hop up) than worry about barrel length (which as far as upgrades go, it's one of the more expensive ones). While it does make a bit of sense that longer barrels should be more accurate, I feel that this is more of a holdover from looking at actual military firearms, where longer ranges use longer barrels, but even that is more because of larger calibers, minimum fragmentation velocities, and flash/sound suppression than accuracy.

I've yet to see a good explanation for why a longer barrel would be more accurate for airsoft, and I've also yet to see evidence. I'm more inclined to believe that barrel length makes no practical difference at all.

Heck, if I had a lathe on hand to cut and recrown the inners properly, I could probably test it myself... But again, what would be an effective test? How do we factor in hop up? Would it be better to use an AEG as a base system because it is the standard that is in use, but have to deal with variable velocities and porting? Or a regulated gas cannon?

[m102404]

First off, THANK YOU for taking the time to write out a decently worded post. It's so much easier to read through and digest.

I don't really mean to nit-pick...but you're dancing around the question posted by the guy who started the thread (at least how I interpret it).

Paraphrasing..."All things being equal...is one better at longer range than the other?" I suppose I'm kind of zeroing in on the accuracy difference aspect of that.

All things being equal...Their barrels are equally firmly attached to the receivers, they're barrels are either both one-piece or two piece, the hopups are the same, the rubbers are the same, the bbs are the same, etc... I'd agree though...yank any front end sideways and it's not going to be good for hitting what you're aiming at. You've got more leverage to pull on a long gun...but only if you're pulling at the front bit of it.

I suppose I'm thinking of the question as BNIB, is one better than the other at long range? Not..."after nocking it around woods, this one holds up better than the other". Not..."how do I take one of the two and make it shoot more accurately"?

Your VSR vs Mk23 example is flawed in this context...they are different guns, barrels, hopups and even propellant sources, etc...

I have cut and recrowned AEG barrels...my CQBR is much less accurate than my M4 (velocities and stuff being "equal"...impossible test, but it's noticeably evident to me at least). Another comparative example would be a TM SOCOM M14 vs a TM M14.

NO argument from me that you can make a short gun shoot well (and shoot better than a lot of long guns on the field) and that there are more effective "fixes" than simply adding a longer barrel, and that simply adding a longer barrel on it's own might yield debatable benefits...absolutely true.

But a longer barrel is still more accurate than a short barrel....all things being equal.

*********really, the real steel internal ballistics are a different topic and forum*********

IIRC, The longer barrel lengths and it's association with "long range accuracy" for real steel comes from the tweaking the pressure curve of the gas build up behind the bullet. Some of the most accurate rounds in short range are so over-bored that they're not very "efficient". But the power curve that they generate is particularly balanced for the bullet shape/size/etc... used for that purpose. As you shoot with bigger rounds, you need to keep that pressure building behind the bullet...and one of the ways to do that is through lengthening the bore (extending the Dwell time I suppose).

The 6mm PPC might be the most accurate round in the world...up to 300-400yrds. At 600yrds it's really just hanging in there. At 800 it's a mess (and the hold over is nuts). Caveate that some rounds are made for punching paper...and others are made for punching meatier things.

[tunabreath]

I dunno, I have a TM AUG that I switch between a cut down stock barrel (really shitty crown, about 300mm, commando) and a KM 6.04 PSG-1 tightbore (factory finish, 590mm, HBAR) and there really isn't any noticeable difference, other than being a shittonne heavier and qualifying as a LSW.

One of my friend's CA36s (full length) shoots worse than another's CA36C with a K inner, both otherwise stock.

Again, it's really subjective. I have to sit down and do a proper test on paper... All other things being equal, it seems... equal in my opinion.

I'm still curious why a longer barrel could be more accurate in the case of airsoft. I can't really think of any reasons... Provided the fps is the same, the BB has no memory of what length it traveled through before entering open air, so assuming it has already traveled long enough through the barrel to be stable when exiting, it should fly the same, shouldn't it?


*I brought up the VSR and Mk23 to show proportionally, just how important everything OTHER than the barrel length was in getting an accurate gun.

[highny]

Man, you guys are giving me all these big terms and all these different gun names... I feel a bit lost reading the replies from some of you(I'm still new to this stuff).

I'm still curious why a longer barrel could be more accurate in the case of airsoft. I can't really think of any reasons... Provided the fps is the same, the BB has no memory of what length it traveled through before entering open air, so assuming it has already traveled long enough through the barrel to be stable when exiting, it should fly the same, shouldn't it?

Maybe longer barrow = different effect on the hop up?

Like the pressure in the barrow is different than the pressure outside(Or open air), so the bb might have more time to develop the back spin so it's spinning on the 90* rather than maybe 85* or less. If the bb's back spin isn't as close to 90* than maybe it'll roll to the side instead of rolling up...

Get what I mean?...


So here's another question:

Let say a pro sniper rifle(in the airsoft world) guy have two gun(m4/m16) infront of him, and a target is walking about 30-35 meters away. There is no wind nothing at all effecting the flight of the bb.

If you were the sniper, which gun would you pick up? And why?

Please try to keep the answer simple for me... The whole reason why I made this forum is to debate if I should add a longer barrow and a slightly different mechbox in a m4 for outdoor games, maybe it'll give me more of a sniper feel, and at the same time, I could assault in a room.

[Styrak]

Originally Posted by sortie39

its a simple question with tough answers!
gernerally speaking, m4 is an upgraded version of M16.

No, just stop right now.

[tunabreath]

Sorry for the threadjack

If you want an honest simple answer, buy what you think looks best, and what you're most comfortable handling. The differences in the way they perform out of the box aren't even worth mentioning.

Personally, if I were the sniper and had to choose between an M4 and an M16, I'd go for the carbine every time. I feel that the shorter overall length is of much more benefit than any potential accuracy gains. It is about 50 times easier to crawl through and over brush with a 7" barrel (the CQD I use currently) than a full length 20" barreled assault rifle like an M16 (G36 in my case), especially since I'm a smaller guy.