http://www.surefiresuppressors.com/s...ence_size.html
Size and Accuracy
Equally important to the shift issue was the matter of accuracy, which harkens back to a question asked at the beginning of this article: how does a suppressor affect accuracy? Improve it, worsen it or make no difference?
Assuming a properly designed suppressor like the M4FA, the answer is accuracy improves - groups tighten up, sometimes significantly, sometimes modestly. The reason is that a well-designed suppressor acts like the world's best muzzle crown, releasing the bullet with perfectly even pressure on the base of the bullet.
Competitive rifle shooters know how important the muzzle crown is for this very reason. The more stable the bullet leaves the barrel, the more stable it carries in flight.
A suppressor enhances accuracy by taking away the turbulence of uneven gas pressure.
To answer the other question posed at the beginning of this article - what affect does a suppressor have on muzzle velocity? the answer is again a bit of a surprise.
A suppressor increases the bullet's velocity, by about 30 to 50 fps, because the extra length of the can behaves somewhat like additional barrel length. While the gas seal behind the bullet is not bore-size tight, the hole in the suppressor is only a few thousandths over bullet diameter, allowing a bit more opportunity for the propellant gases to accelerate the projectile.
By comparison, an extra 5" of rifled barrel might add 200 fps to 300 fps while 5" of can will only up the velocity about 30 to 50 fps. Still, any increase is an increase.
Speaking of length, the SureFire M4FA adds only 3.75" to the overall length of the weapon, compared to over 6" for the currently issued SOPMOD can. The bulbous length of the current issue can alters the weapon's point of balance and makes it unnecessarily unwieldy. Combined with the extra weight of the unit, the SOPMOD can adds up to a heavier, bulkier, longer can than the lightweight M4FA.
And so now the M4FA suppressor design was optimized. The point-of-impact shift was negligible, the affect on accuracy was beneficial and the terminal ballistics of the cartridge were actually improved. Only one final test remained, and it was brutal.
The common mis conception on silencers comes from its name. They are officaly Flash and Sound Suppressors. They're not made to make you silent, just invisible. Just read the link there are plenty of articles to read. Suppresors on assult rifle's are used to get rid of muzzle flash, and to controll recoil.
Now your a Marine, and Im assuming you did night training. Now imagine if you are being shot at, durring night time, and you can't see where your being shot from. And imagine your M16/4 with reduced recoil. Because we all know the M16 has some nasty recoil

.
On a side note: Commader, nice job.