Those of you who were/are in the military:

What are your thoughts on a semi-automatic weapon versus an automatic weapon in a combat situation? Does the number of opponents and what they're armed with matter to you? Is it a matter of personal preference, ammunition cost, penetration/stopping power, or some other facet I'm not considering?

It depends on the scenario, really. What are you considering? Why are you considering it? Have you shot a weapon before? What type of experience do you have? Will you be attacking or defending?

Auto and semi auto have there places, but it depends on mission, equipment, time, type and terrain. METT-T

Full-auto is pretty useless in MOST enviroments. Its a great tool for laying suppressive fire, but outside that, for most soldiers/shooters, its an all to easy way to burn off WAY to many rounds that will be needed later.

Semi Auto versions of most weapons systems is ideal. A burst system can be valuable depending on the situation, but I have seen in real world operations that once you get good trigger control with a semi-auto, you can phase out the burst options.

A HUGE downside to auto or burst is the beating your weapon takes. If your in an arena where repair or replacement are as easy as going to your armor, then fine, but for a long haul operation you need reliability and endurance of every part, and that comes with semi-auto set ups.

Bottom line...it may look cool to shoot full auto, it may feel cool to shoot full auto, but the reality is semi auto is hands down the most effective and reliable means on a personal weapons system...outside your obvious machine guns...but they have their own purpose.

Automatic only purpose is either suppressive fire, as rc said, and room clearing. The submachine gun was invented for WWI as in-trench fighting was close range and high volume of fire gave them an advantage over the standard issue bolt rifle.

Not that bolt is bad, NO NO. I prefer bolt-action myself.

Automatic is a good way to miss. The recoil is atrocious and not much to show for it. Semi-automatic tends to fire as fast as you can squeeze the trigger for the most part. It will be more than adequate in ANYthing you do, it will work for suppressive, anything will, though not as well. The point of suppressive fire is to make them fear shooting back (as they will get shot).

Again, semi-automatic shoots as fast as you do, with less recoil, and way more accurate, than automatic. Less volume of fire, but hit ratio is far higher as result, and thus conservation of ammunition (as stated again by rc).

Automatic weapons are really only good for intimidation and suppressing fire the muzzle climb severely hinders the accruacy of the gun even on small calibers. With a Semi-Auto you will be able to get off well placed rounds accurately with a better chance hitting your target. Now in close quarter combat muzzle climb isn't as much of an issue because your target is usually 5-50 feet away so for close quarters I think auto has the upperhand. However in close quarter combat there is no gun more effective than a 12 guage shotgun and that has the upperhand on just about everything for that purpose. For Home Defense there is no better choice than a shotgun, load it with "000" Buckshot (000 is pronounced triple aught).

I recommend for home defense getting a pump action shotgun mainly because its less prone to jamb making it more reliable and secondly if there is a intruder in your home once you pump it to load a round in the chamber everyone knows what that sound is and most likely the intruder will get the hell out of there as fast a possible ending the encounter peacefully without putting holes in your walls. Just my 2 cents.

semi in my opinion , you ll save bullets and get better accuracy.

then again its a question of what its going to be used for , if hunting then you ll do fine with a single round system rifle and a semi hand gun.

if its for protection of property and family during a "fallout scenario" then guns/rifles is just one step for protection but as a starter a good assault shotgun with a good recoil damper ,you can practicly hold it shot it with one hand and get good accuracy

but as reality sometimes bite back you have to remember that its only your tools aslong as you stay alive.

I'm kinda surprised that someone actually asked this question. The difference between semi and full auto should be obvious. One shoots one bullet per trigger pull, the other shoots until you release the trigger or run out of ammo. The ammo is the same, so the stopping power is the same unless you manage to land multiple rounds from an automatic weapon. If you're asking the question, you likely can't.
Also, if you're asking the question, and truly don't know the difference, automatic weapons are likely illegal where you live. You'll have to go to the streets to find something automatic, or buy a semi and convert it to auto, something else you likely won't be able to do.
Also again, if you were to get your hands on something that had automatic capabilities, you'll likely have a selector on the gun to switch from semi, full, or burst (depending on the gun), so you can choose for yourself which you like best. But again, if you're asking the question, it's probably best to leave the home protection to someone slightly more qualified until you take some classes.

And to those here who are recommending a pump shotgun as the be-all-end-all for personal protection, while the sound of the rack is intimidating, riddle me this...

Say you hear a strange noise in the night, something that shouldn't be there. The little wifey urges you to get out of bed and check it out, so you get out of bed in just your boxers and lumber over to the closet to fish out the handy Winchester or Mossberg pump shotgun that you keep hot and ready to go. You stand in your upstairs bedroom doorway, listening. You hear the sound again, and seeing as you have that massive, intimidating piece of personal protection in your hands, you holler out "I'll give you ten seconds to leave this house, I have a gun", and rack a shell into the chamber, just for effect. You hear footsteps and see a shadowy figure run across your field of vision so you fire off a round, spreading buckshot across your living room wall. Maybe it wasn't your living room wall, maybe all of those pellets just imbedded in, or penetrated the wall of your childs room. Not two seconds later, the intruder comes out from cover and pulls the trigger five times, sending five .40 caliber bullets your way...all without cocking a hammer or racking a pump...all before you can even think of re-racking that shotgun.

-OR-

Take that same scenario and say in your fear or nervousness, you forgot to even rack the shotgun in the first place. Someone appears at the end of the hall. You pull the trigger and "click". Nothing. You just became mortally wounded or dead.

A shotgun is great, and intimidating, if used properly. But for the average person who isn't a gun expert, doesn't hunt, or doesn't spend countless hours on the range the least amount of moving parts necessary is best.
Take a semi-auto pistol. It's the same each time, and the work done to get ready for business can be done before the danger is imminent. Insert magazine, rack slide and go. You have 5-10 shots at your disposal and all you need to do is pull the trigger. Take a hammerless or a revolver that doesn't require a hammer pull...at least 5 shots without interaction.

A shotgun with buckshot is great because of the spread, but in that second or two required to re-rack, a lot of bad things can happen.

I agree with the posts so far.

Semi is good unless we are talking about real machine guns, and those use bursts for effectiveness and to reduce overheating/warping the barrels.

In real terms, accurate fire is effective fire. Remember the Marine Corps motto of One Shot One Kill, and those boys aren't lacking for ammo like us civilians.

Unless I'm fighting an army in a suburban situation with more ammo than I can carry for a long time, Semi Auto.

If the enemy is far away, Scoped Bolt Action. But if the enemy is that far, I'd prefer to just keep moving (unless it's someone who's been following and hunting me.)

[edit on 18-3-2010 by Miraj]

Look if I'm standing behind a Ma-Deuce I'll going to be yelling "Rock & Roll"!
but there was a reason the M16A2 was designed to shot a three round burst. Full auto is best used to suppress enemy fire... make them keep there heads down while others advance on them...Besides with the M4/16 class of weapons Magazine size does limit how many times you can do that before running out of Mag's

It never was all that easy to keep on target during a full auto burst... they teach you short bursts, best with two machine guns...(Talking Guns) one fires a burst, waits while the other fires his burst, then you shoot your burst again. keeps your from melting your barrel too!

Just this past weekend my boys and I went out to the range to shoot, no autos mind you but jest messing around we went through 500 rounds and were only out there a couple of hours...that's why we don't go every day... If I had a full Auto that 500 rounds would have been gone in minutes not a couple of hours



[edit on 18-3-2010 by DaddyBare]

I think it really depends on what semi auto vs full auto and the situation.Like i would take a semi auto ak over a full auto glock any day.

Originally posted by DOcean

Say you hear a strange noise in the night, something that shouldn't be there. The little wifey urges you to get out of bed and check it out, so you get out of bed in just your boxers and lumber over to the closet to fish out the handy Winchester or Mossberg pump shotgun that you keep hot and ready to go. You stand in your upstairs bedroom doorway, listening. You hear the sound again, and seeing as you have that massive, intimidating piece of personal protection in your hands, you holler out "I'll give you ten seconds to leave this house, I have a gun", and rack a shell into the chamber, just for effect. You hear footsteps and see a shadowy figure run across your field of vision so you fire off a round, spreading buckshot across your living room wall. Maybe it wasn't your living room wall, maybe all of those pellets just imbedded in, or penetrated the wall of your childs room. Not two seconds later, the intruder comes out from cover and pulls the trigger five times, sending five .40 caliber bullets your way...all without cocking a hammer or racking a pump...all before you can even think of re-racking that shotgun.

Well for me the answer to this is simple, I live by myself and no kids and also have a brick home so overpenetration isn't a big issue with me. Also there is no need to re-rack another round in the chamber unless there is multiple intruders, if you hit an intruder in center mass with "000 Buckshot", they are down period even if they have a bulletproof vest although it may not be lethal but it will break quite a few ribs and knock the wind out of the intruder and the shock of that would take quite a bit to be able to get back up.

Your scenario that you have laid out goes for all guns not just shotguns thats why when choosing Home Defense ammo you need to consider overpenetration especially if walls are thin, kids present, neighbors house is close to yours and so on. If thats the case then Frangible ammo is the way to go because the bullet breaks up on impact. Also people that are not experienced with guns should never even use or attempt to use a gun unless they are well versed on how to properly handle it. Semi-Auto shotguns jamb frequently depending on the shell i have a Remington 1100 semi-auto and it collects dust because clearing the shell after a jamb is a pain yet my Remington 870 pump has not once jambed on me and I've put well over 1,000 shells through it. Most of the time simple is better with any mechanical device, and in a life or death situation simple is most definatley better.

I'll keep it short and sweet. Given 3 modes of fire, semi-auto, 3 rnd burst, and full auto, I'll take 3 rnd burst first, then semi-auto.

Even a "light" weapon, typical M16 or M4, based on .223, is going to "climb" on you. I don't care how much of a muscle man you may be, the weapon is going to travel. You end up making noise, wasting ammo, all for nought. Other than just plain old fun.

Burst you can handle, the rounds are on their way before the weapon can really start to drift, and you're reset for the next burst. Semi-auto, can be nearly as good, and you retain full control of your weapon.

Now, if the full-auto weapon is mounted on a fixed platform, that's another matter. But it sounded as if you were speaking of rifle type weapons.