Just bought some bullets... [Archive] - Glock Talk

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wrx04
10-10-2010, 21:09
Just bought my first batch of bullets. My press should be getting here early next week, so i've been getting all the components i need. I went with montana gold 230gr fmj. I bought 1000 to start, so hopefully these will work fine.

Questions:

What is the difference when a bullet is labeled CMJ compared to FMJ? I know one is full metal jacket, but what is CMJ?

Second, do you guys mostly shoot cast lead bullets or jacketed? Is there any benefit to the jacketed that warrants the price difference?

rjrivero
10-10-2010, 21:14
CMJ is "Complete Metal Jacket" which means the rear of the bullet is also encased in Copper.

A lot of the Copper Plated bullets (Versus true Jacketed bullets) will have the base covered as well. This means less vaporized lead to inhale in indoor ranges.

The only difference between lead and copper is the exposed lead. Some indoor ranges won't let you use lead bullets.

When it comes to bullets, the cheaper plated bullets, Rainier, Berrys, Powerbond and others are not truely Jacketed. The plating can come apart if pushed too hard. I don't push them past 1200 fps in any caliber. You will also find more bullet to bullet weight variance in the plated bullets. For plinking, I don't mind. For USPSA and Three gun, I don't mind. If I'm really concerned about accuracy, then I would mind.

Hope this helps. Enjoy your "new" hobby!

Bucky89
10-10-2010, 21:14
The difference between Complete Metal Jacketed bullets and traditional Full Metal Jacketed bullets starts with the manufacturing process.

Full Metal Jacketed bullets are manufactured by means of pressing ("swaging") a lead core into a copper jacket while the jacket of a CMJ is electroplated onto the lead core, covering the core completely. Through the years this process has been refined continuously to improve core-bonding, smooth plating and other factors, resulting in a premier product. Among the many advantages of CMJ bullets is the fact that the lead core is completely covered with copper, eliminating the dangers of lead poisoning. The manufacturing process s more flexible, resulting in a product that is easier to customize for specialized use.

njl
10-11-2010, 20:29
The difference between Complete Metal Jacketed bullets and traditional Full Metal Jacketed bullets starts with the manufacturing process.

Full Metal Jacketed bullets are manufactured by means of pressing ("swaging") a lead core into a copper jacket while the jacket of a CMJ is electroplated onto the lead core, covering the core completely.

AFAIK, that's how Speer makes their CMJ/TMJ bullets...and even some of what they label as FMJ. i.e. take a box of Blazer marked as FMJ and pull a bullet. But not all CMJ is electroplated. Montana Gold CMJ is a lead bullet with a gas check on the base and then an FMJ jacket wrapped around from the top. The result is basically FMJ with the "exposed lead base" covered by a gas check tucked into the jacket.

Boxerglocker
10-11-2010, 21:05
Second, do you guys mostly shoot cast lead bullets or jacketed? Is there any benefit to the jacketed that warrants the price difference?


I know many will answer the first but for the second question my thoughts:

I prefer FMJ for my 9mm requirements. I believe FMJ to be more convenient all around, no lube to mess up the dies and thus less often do I need do clean them. Less smoke issues when firing. I shoot at a variety of places a lot of them indoor where though yet to be banned, exposed lead bullets are frowned upon. My 9mm guns consist or both polygon and standard rifled barrels. Shooting FMJ lets me stay with one standard 124g FMJ load for all of them. I gave up my aftermarket barrels in the Glocks for lead (sold them to buy more bullets.). One standard load allows me to buy larger bulk quantities for bigger discounts. $70 a thousand for 124g FMJ.

In my Kimber, I use moly coated lead 200 g RNHB from Bear Creek. We have a local distributor that is a member of our club. I buy those at $36 per 500 if I buy three boxes at a time. I only go through a box a month so it economical enough. The moly is tough and not messy, being I shoot it solely in my Kimber. I don't even clean the barrel. Just push a dry patch through it once in a while after I clean the chamber. It leaves a nice even coat of moly that is said to enhance itů so far no complaints.

GioaJack
10-11-2010, 21:28
I'm too cheap to shoot anything other than lead plus casting indoors helps keep me in perfect health.


Jack