Can I get some recommendations of efficient sentry gun placements?

Has anybody produced a guide or can give me tips on sentry gun placement in call of duty; my sentry guns are always picked off pretty quickly. I understand sentry guns are prone to a lot of attacks, but if anybody could give me some tips of where to place on the various maps, I'd appreciate it.

Thanks.

Check the heat maps in your recent games section to locate the high traffic choke points which are the prime locations for your sentry gun.

If you have access to the Call of Duty Elite beta, that site lists all of the maps including spawn points and objective locations (depending on game type) so you can further plot your automated mayhem.

Put the Sentry gun in a high place facing a choke point. Specifically on top of something that would require them to climb instead of just walking to it (blown up cars would work well). The higher the better but make sure it is still facing a high traffic area.

Placement is one factor, defending your installation is another.

Sentries are the Ghost Pro players' speciality, and you must protect your equipment from flash/stun grenades at all times, so staying in a hole or at an ambush point near your sentry is a very good idea.

On a more active approach, place a claymore or a C4 around your sentry, especially on paths where you think the enemy will approach from. Flak Jacket Pro might be of use here, if you are in the open or otherwise too far in a shelter to protect it.

There are two places I normally place my sentry guns: on long sight lines and in corners. When you place one on a long sight line (usually a long hallway or open gap between buildings), you have the potential to rack up kills because it may take opponents too long to zero in on the sentry gun the first couple times. Also, the sentry guns seem to have a significant range, so it will shoot them even if it only sees them briefly. However, the downside to this is that it is usually easy to sneak up on from behind.

Example: place the sentry gun on top of the rock platform on 'Jungle'. It can usually depress far enough to cover a large area of the jungle floor. Also, it is hard to flash in that position. However, a skilled player with a rocket can take it out fairly easily and it is extremely easy to sneak up on from the back.

Placing a sentry gun in corners allows the sentry gun to last longer, but often at the expense of slower kills. A lower coverage area means the sentry gun may not see as many people.

Example: place the sentry gun on 'Hanoi' on the raised grass area near the 'B' flag is on Domination. It will be harder to sneak up on, but its reduced sight line may mean fewer kills.

The heat maps idea as said above is great, and once you play for awhile, you will likely instinctively know the heavily traveled areas. Ideally, you could place the sentry gun in a corner with a long sight line down a choke point. However, few such positions exist. Sentry guns are easier to use on smaller maps, like 'Nuketown' and 'Firing Range', so placement is much more important on larger maps. Good luck and happy killing!