TMJ VS FMJ for 10mm

[al8550]

So I'm attempting to reload for my 10mm but my recipe book calls for 180gr TMJ, however I currently only have 180gr FMJs. Can I substitute the FMJs or am I asking for trouble???

[Bill Steele]

So I'm attempting to reload for my 10mm but my recipe book calls for 180gr TMJ, however I currently only have 180gr FMJs. Can I substitute the FMJs or am I asking for trouble???

If it is the same profile bullet (i.e. RN, FP, etc.), then you can use the same load spec. If it is a different profile, then the OAL might change.

[Lead Waster]

It's possible that TMJ (total metal jacket) is a plated bullet, rather than have a thicker copper jacket.

So the TMJ load is probably less than the FMJ load so I think you will be OK in terms of overpressure, etc.