I own a 6mm Bellm TC barrel that i bought 18 years ago. This cartridge is based on the .225 Win case fireformed 40 degrees. I cannot find any reloading data for it. Is the 6mm JDJ round close enough that i can i use 6mm JDJ reloading data ?

I would e-mail Mike himself and ask for data, if you can't find any info here.
mike@bellmtcs.com

Here is a link to the only 6mm cartridge that I knew Bellm made. I'm sure he had more.
It was a 6x50R. This link has the load data and history of it.
Mike
6x50 R Bellm

Mike Bellm responded to my email two weeks ago.He referred me to a man who also has a 6mm Bellm ( 6mm/225win./improved) However that gentlemans loads were limited to one each for a 55gr and 70gr.using 35.0 of AA2520 powder. Does anyone know, are the 6mm Bellm and the 6mm JDJ basically the same?

Can you find the specs for the JDJ round in any of the loading manuals? If so compare them against your own measurments. My guess is that it would extremely close If they both use the same parent case and neither of them is shortening it. I think that JD's are 40 degree shoulders. It would end up veing the difference in body taper. Sounds to me if the above is true they are very similar sort lof like the 284 Win and the 280 Rem. Very Similar (Ballistic twins) but still different.

Nozlers 5th edit. page 528 shows a JDJ 6.5 as using the .225 Win case blown out 40 degrees.So i will have to assume that the 6mm is similar. Now all i have to do is locate some 6mm JDJ load data.

Cappi

What you are looking for is data for the 6JDJ #2. The 6JDJ doesn't have the 40 degree shoulder (not that you would ever run across the non "improved" version )......

I have some data from SSK for the 6 JDJ #2. I would offer to scan and e-mail the data, but my copy is not very good and I don't think trying to reproduce it would work out.......best bet is to call SSK and ask for a load sheet.

Until then, I'll be glad to give you some of the loads if you tell me what bullet you are interested in.....

I would like to reload for Hornadys 75gr. V-Max and any 85gr.- 87gr. heads. Thanks

Cappi

This is all the SSK data. CCI 200 primer in all loads.......reduce by 10% and work up......as always, use of this data is at your own risk.
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70 grain Nosler Ballistic Tip 2.55" OAL

RL-15 35.0 grains 2780 fps

AA-2520 33.0 2753

IMR4064 34.0 2744

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80 grain Hornady Single Shot Pistol 2.57" OAL

RL-12 32.5grains 2616 fps

IMR4064 33.5 2629

H4895 32.0 2619

RL-15 34.0 2671

IMR4350 37.0 2535

RL-19 39.0 2586

AA2520 32.5 2713

H380 35.5 2487

H414 36.0 2519

IMR3031 31.5 2565

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85 Sierra BTHP 2.54" OAL

RL-15 33.5 grains 2645 fps

AA 2520 31.5 2598

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90 Speer Spitzer 2.66" OAL

RL-15 32.0 grains 2524 fps

AA2520 31.0 2541

H380 36.0 2625

Thank you so much for taking the time to help me out.

You are welcome......after visiting with a couple of other 6JDJ #2 owners......the velocities listed in the SSK data may be a bit lower than what most folks see........