Is a Full Metal Jacket bullet the same as a TMJ (I assume Total Metal Jacket)?

I am getting ready to buy 1000 TMJ bullets for my .40S&W and want to know what load data to look at.

I have been loading using Ranier Ballistics hollow points. Having problems with over pressure. I am loading according to load data (minimum load) but still getting velocities WAY over what I should be - 1500 fps. I had to drop the powder charge well below minimum to get them to shoot like they should. Not sure what is causing this!?!?

A lot of FMJs are just that except the base. TMJ would/should indicate a complete jacket that is closed at the base.

When we say "work up your load" that means when you reach top acceptable pressures - stop. If you are getting excessive pressure/velocity from any load, reduce it or go to another powder.

Rainier recommends using cast bullet load data, are you using this data or jacketed bullet data?


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Ranier bullets are not really jacketed, they are plated which is a huge difference. Always use cast loading data.

Don't forget that the data in manuals was made from using an actual firearm or test barrel. With that said your firearm may and will vary from what they got. That is why you should always start very low and work up.

Normally FMJ bullets have a pretty thick gilding metal jacket. Pretty much similar to a soft point or hollow point jacket. The TMJ are plated and are copper. They are much thinner. The bullets are generally much softer then FMJ's and your problem may be that they are really obturating to the bore more so then a harder FMJ bullet and increasing friction and raising the pressure. Try your same load that you said was showing pressure with the TMJ with a FMJ and see if it still shows pressure. If it does then something is much different about your barrel and/or your powder lot.

Rainier bullets are copper plated, not jacketed. That is why they recommend using cast bullet load data.

Thank you all for you input. I got my load data directly from Rainer and started at minimum charge and got the velocities in my original post. Never went above minimum.

That is why I am going to try these other 180 gr TMJs. The Rainer's shoot fine now that I really reduced the load but it seems odd to me that Rainier would give such "hot" load data as their minimum. Maybe it is something about the way I loaded them. Who knows...