Both based on the 444 marlin case. Are they ballistically the same. One any better than the other?

I don't have the ballistics in front of me, but the JDJ is faster. I'm thinking maybe up to 200fps with the heavier bullets, but I may be off there. On the Bellm there is a LONG neck that decreases case capacity. If you don't need that last little bit of juice the Bellms are fine cartridges.

Link to 308 Bellm Ballistics

http://www.bellmtcs.com/BellmTriad/308bellmdata.htm

I have a 309 JDJ and I'm shooting the Nosler 165 BT @ 2325FPS. The 309 is a little faster with all bullet weights.

Hornady 5'th Edition
309JDJ I listed MAX velocity
110 gr V-Max orSP 2900FPS
130 gr 2600 FPS
150-155 gr 2500 FPS
165-168 gr 2400 FPS
178-180 gr 2300 FPS
190 gr 2200 FPS
220 gr 2050 FPS

hmmm link is missing????

Sorry about that. I went back an added the link and the MAX 309 JDJ velocities from Hornady's 5'th additon.

Jay

Ahhh thats better thanks for the info

I thought the Bellm wildcats were based on the 45-70 case which is weaker by design. I thought that was the reason JD Jones went with the 444 marlin case. As always, I might be wrong.

Bellm's are all based on the .444 Marlin case. Major difference between his and JDJ's is the longer neck as mentioned before. What this does for you is it enables you to reload them without needing special dies. The .308 Bellm, f'rinstance, can be reloaded using .308 dies. My .358 Bellm can be reloaded using .358/.356 Winchester dies. I don't know what the typical velocity differences are, but in my .358 Bellm, I'm getting about 2240 fps with a 200 gr. bullet. I could push it faster than that, but I think that's about the max pressure the frame can handle in that round.

The other difference between the Bellm and JDJ design is that the JDJ design is an IMPROVED cartridge case design in that it has minimum body taper and a 40 degree shoulder while the Bellm is simply a rimmed .308 with a slightly longer body and longer neck made from .444 Marlin Brass.

Larry