I would like to know if you have/had a 6.5 JDJ what kind of velocities you were getting? I'd also like to know what bullet & powder you were using.

The reason I'm asking this is so I can compare the 6.5 JDJ to another cartridge. I would like real life numbers to compare.Thanks!

Rich: 34.5 grains of Re-15 will give you a shade over 2400 fps with 120 grain bullets (Speer Hot Core and Nosler BT), which happen to be the weight that makes the cartridge shine. A couple other powders will get you to the same level, but Re-15 has been the most consistent and with the best accuracy in my usage.

The Nosler 125 grain Partition will do 2325-2350 fps with several powders, incl. H4895, Re-15, AA2520 and IMR-4320.

Lighter bullets don't fare as well, but you can count on 2650 fps with the Sierra 85 grain HP or around 2550 with 100 grain bullets.

By the way, all of the above velocities are from 14" barrels.

Rich-May I ask which cartridge you are comparing it to? If it's the 6.5x50R Bellm, I'd be happy to provide those numbers as well.

In the event that's the cartridge, it'll do 2500 fps with a 120 grain bullet from a 14" barrel -- a custom barrel, I might add. You won't get that with a re-chamber of a standard TC tube.

The Bellm is a neat cartridge , but considering the problems with differences in neck thickness with various lots of the Hirtenberger brass and the cost of RWS cases, the JDJ is a better (read that as "more practical") way to go -- at least for now. Also, the Bellm round would be better off with a slightly longer neck. You wouldn't lose enough in powder capacity to make a bit of difference, and there'd be better neck tension with projectiles such as the Nosler BT. A slightly longer neck would also minimize problems with the thin lots of the Hirtenberger brass as the additional bearing surface would provide more tension.

Well Bobby since you asked. I have been working with the 6.5X50 Jap rechamber done by SSK that belongs to TCLouis. I will be posting an article on my results later on. The case holds about a grain more than the 6.5 JDJ in the reloading data. They both use some of the same powders. The only draw back that I see with it so far is the sharp taper of the case. So far I have only loaded Imr 4350 & was able to equal JDJ velocities once. I have been able to improve on the consistency of the loads in comprison with factory ammo. I have at least two more powders to try out & then I have to decide from there if I need to continue on or end it there. So far it has been interesting.

I have always kinda wondered what performance you would get in a carbine length barrel in 6.5 JDJ. You think you could safely push one to starting .260 levels ? How much trouble do you have locating .225 brass to work with ? 4350 seems like a very slow powder for a 6.5 specially in a pistol length barrel.

Rich,

As usual, Bobby has pretty accurately summed it up. My personal experience w/ the 6.5 JDJ has been pretty similar to his. I've had best results on big game (whitetail deer, mule deer, and antelope) using 120 gr bullets, mostly NBT's, but a few Sierra's; have yet to kill anything w/ the Speer. I've also found RL 15 to be my favorite powder for 120 gr bullets, although H4895 has started making a significant push lately. RL 15 pushes the 100 gr NBT to 2575 fps. RL 15 and H322 push the 85 gr Sierra HP to 2750 and 2680 fps, respectively. When I do my part, all the above loads will print less than, or equal to, 1" groups at 100 yds. All loads are from a 14" barrel. If you want more specific load data, let me know.



I couldn't reach 2400 fps w/ 120 gr bullets in my barrel w/ the powders JD recommended at the time ('92). These powders included: IMR 4320, AA2520, H414, and IMR 4350. Also couldn't get desired velocity w/ AA2495 BR, AA2700, and RL 19. H335 and H322 burning rates were too fast w/ the heavier bullets, but ok w/ lighter bullets. AA2015 BR looked, and behaved, very much like H322. JD rec'd only using Australian made H322, so that's what I used. Since my initial developmental work, I've also tried Varget, VV 140, and VV 130, but again the velocity was subpar (w/ 120 gr bullets). 748 may have some promise, if I ever get a chance to play w/ it some more.



SKB, I think one would have a hard time safely reaching 260 Rem RIFLE velocities using the 6.5 JDJ in a RIFLE. You might reach "starting" 260 Rem velocities w/ the 6.5 JDJ, depending on how one defined "starting." Don't have the loading manuals in front of me right now, but in comparable handgun barrels, seems like the 6.5 JDJ lags a couple hundred fps behind the 260 Rem; I'd expect that difference to hold up in rifle barrels, as well. I agree w/ you that 4350 would seem to be rather slow burning powder for the 6.5 JDJ. Personally, my velocity results w/ it were very disappointing compared to the load data I received w/ the barrel. I've not needed to buy 225 brass since I bought my 6.5 barrel, but I still see it available in wholesale catalongs; in addition, I imagine SSK will always keep it on supply. Guess I'm not worried about brass availability as I recently bought a used 257 JDJ barrel, as well.



Gary T.

skb-Because the 6.5 JDJ is a fairly efficient cartridge to begin with, you won't gain a significant amount going to a 22" or even a 24" barrel. 2575-2600 fps will be about tops with 120s.

H4350 may seem slow, but a compressed load will give you 2375 fps (14" bbl., 120 grain bullets) in a 6.5 JDJ. Keep in mind that what works best in a cartridge in rifle-length bbls will generally be your best choice in 14-15 in. pistols as well. I don't know where it started, but the notion that one must step down to faster powders for rifle-type calibers in specialty pistols just doesn't hold water.

Also, as Gary T. noted, brass for the .225 Win is very easy to find.

Bobby
Could you give me a starting point with RL15 ? It may work well with what I'm working with.

Rich-With the 120 grain bullets in the 6.5 JDJ, I'd start around 31.5 grains and work up a half-grain at a time. I use 34.5 grains with the 120 grain BT, and it is not quite max (35.5 grains is what my particular rig showed to be max). But that level -- 34.5 grains -- gave me top accuracy.

Also, I gained virtually no velocity when adding more than 34.5 grains of Re-15.

Rich-One thing I failed to mention and something that you probably have already encountered: The taper of that case is not well-suited to Contenders and will tend to drive up pressures and increase backthrust against the frame. Even though it is basically the same capacity as the 6.5 mm JDJ, I seriously doubt you'll get within 150 fps of top-end JDJ loads before getting into the red zone. If you basically equal the performance of the JDJ, you may be stressing the frame...

Thanks for the thoughts Bobby. I have been working the loads over the chronograph. I have also been watching the primers as well. This cartridge uses large rifle primers & I use Mike Bellm's recomendation for watching for max pressure.

Continuing your charge increases from the first appearance of the breech face signature, at about the same point the case web stops growing, give or take a little, you will start to see a little imprint from the rimfire firing pin hole on the top edge of the primer. Once this rimfire firing pin hole imprint starts to appear, you are within just a couple grains of absolute max. I.e., you may well be able to go above this point several grains before the barrel becomes hard to open, but don't do it...... You are standing at the edge of thin ice, safe enough for the minute, but take another step or two, and you'll be in over your head. SO STOP WHERE YOU ARE AND BACK UP A LITTLE.

So I feel I have a good feel where the max is. With the Imr 4350 load that I worked up 2300 fps was max. I went beyond that started getting diminishing returns & what Mike wrote about. So 2300 was max with that barrel & bullet combo.