Military rounds in general are cheaper than other ammo.

The 9mm is a military round and it is the cheapest.

The .40 is a police round and used quite a bit and it is in the middle.

The 10mm is almost semi-exotic--I rarely see it being shot; it is the most expensive.

Google "Winchester White Box prices" and you will get a better picture (practice ammo--"ball"). Or just walk into a Wal-Mart and ask their prices. (Not all Wal-marts carry guns and ammo.)

Originally Posted by flw

Which types cost more in general with the from the same mfg- FMJ 9mm, 10mm or 40 S&W

Below is the link to the Midway USA ammo page. A good source of info.

Ammunition - Shop Premium & Discount Ammunition at MidwayUSA

This page has link to each of "the most popular handgun ammo" calibers on top.

Below is a link to each of 62 different handgun calibers. Including the "most popular" above.

Clicking on a caliber link shows all of the ammo brands/types Midway offers for that caliber. Including price. And bullet weight(grains).
Clicking on the ammo picture shows a blurb about the ammo. Plus, the velocity in fps and energy in ft-lbs.

My only disclaimer is you have to note the number of rounds/box for pricing.
"Practice" or "ball" or "target" ammo is usually FMJ (Full Metal Jacket) in semi-auto calibers. Generally 50 rds/box.
"Self-Defense" or "Premium" is some form of hollow-point design. More $'s/rd. Usually 20/25 per box.

Make yourself a "table" to record "the data" per each caliber, with a couple of samples each of "target" and of "self-defense".
Caliber Bullet Wt.(grains) Velocity(fps) Energy(ft-lbs) Type(target/SD/etc) Brand No/Box Brand

In about 15 minutes you can get a really good answer to your question. And learn a lot about ammo.

+1 on the comment above about 9mm Luger or 9mm NATO or 9mm x 19mm (length) as the cheapest.
Different names for the same caliber. A gun history lesson is "involved" here.

Monday I bought two boxes of "9mm Luger" at the Phoenix Cabela's "on special".
115 grain FMJ (ball). 50 rd box for $10.99. This is a buck above the old-time "standard sale" $10/50 rds.
Brand was MFS. Magyar Loszergyarto Zrt. That would be the "Hungarian Ammunition Manfacturing Inc."

The cartridges "look" good. Another byproduct of the end of the Cold War and the start of capitalistic competition.

Originally Posted by flw

Which types cost more in general with the from the same mfg- FMJ 9mm, 10mm or 40 S&W

Thank You,

flw

Using the link provided by DanP_from_AZ, above, I selected one brand that I commonly see in my local area, and picked a common bullet weight in each caliber. Exact results will vary, but this should give you an idea of the basic relationship between the cost of these three rounds (click each link to see the description and cost):

9mm
Federal American Eagle Ammunition 9mm Luger 115 Grain Full Metal Jacket Box of 50 - MidwayUSA

.40S&W
Federal American Eagle Ammunition 40 S&W 180 Grain Full Metal Jacket Box of 50 - MidwayUSA

10mm
Federal American Eagle Ammunition 10mm Auto 180 Grain Full Metal Jacket Box of 50 - MidwayUSA

Keep in mind that if you buy on line and have it shipped to your home you have to have an adult in person sign for the package. Perhaps that works for some; it does not work for me.

The alternative is to have this shipped to my place of business which is OK if the company name does not sound like guns or ammo.

In my case, the easiest way out is to go to Walmart. I bought some 9mm Winchester White box 9mm ammo recently. I think I paid about $25.00 for the box (100 rounds) so that is fairly competitive and eliminates my shipping worries.

http://www.ammoengine.com/find/ammo/10mm

9 mm - Cheap
40 S&W - not as cheap.
10 mm - Getting pricey.

If you wish to shoot 10 mm or other expensive ammo, reloading becomes an attractive option. Setup costs are paid off quicker.