I looked at the "real guns" article on the 500 Jeffery and thought, maybe I should try IMR 4350. A 570g TSX at 2500 fps should be impressive. The max load tried in the article was 126g IMR 4350 with the 570g TSX which is my favorite bullet so far for the 500 Jeff. I didn't realize with the length of the TSX the extent the powder would be compressed.


Well, I got back from the range. I loaded 3 rounds of each with all rounds using the same brass, primer, bullet and OAL

570g TSX, Jamison Brass, Federal 215 primers OAL 3.63 for all loads

My control (and favorite) load to date is:

103g H4895 2320 fps avg spread 10 fps accuracy better than .75" at 100 yards, recoil invigorating but shootable and enjoyable

The IMR 4350 loads I tried and results are as following:


122g IMR 4350 2410 fps avg spread 20 fps, compressed, accuracy for the one group 1.5" at 100 yards recoil about the same as my control load

124g IMR 4350 2470 fps avg spread 40 fps more compressed, accuracy a bit worse recoil getting stiff

126g IMR 4350 2570 fps avg spread 80 fps very compressed load accuracy over 2" at 100 yards, recoil unpleasant


Conclusions: I'm staying with my tried and true load of 103g H4895. I'm guessing that if I was loading 570g Swift A-Frames the loads wouldn't have been so compressed, velocity variance would've been less and accuracy might be better. I will probably try them after elk season. A worthy experiment, no shoulder bruises, no headaches, no ill effects on rifle or shooter



colorado, 38 minutes ago Report

"126g IMR 4350 2570 fps "
Impressive chuck any pressure signs??
Maybe more easy with the shorter a-frame bullet to ge the same velocity but with not as compressed load.

No pressure signs, but it's only 70 degrees today. I'm not sure I'd try the 126g load at 90 plus degrees. No flattened primers, the web's look good, easy extraction.

Those are some impressive results...2570 fps with a 570 gr. TSX is certainly no joke! Have you considered playing around with the seating depth? You've got plenty of room in the magazine of your CZ to load them considerably longer which would alleviate your compression issues and might improve accuracy.

I have seated out TSX's to an OAL of 3.73" in the past. I think that's OAL the real guns article used. I should've tried that. Maybe next time at the range. It will cut the velocity some, but probably at the 126g level cut down the velocity variance and improve accuracy. I also want to try my Swift A-Frames with my 103g H4895 load and experiment with seating depth as well. Elk scouting will take precedence. If I take an elk with my 500, I will definitely post a picture. I don't have time to go anywhere sexy so will hunt on our land and our neighbors up in Guffey, CO.

570grain at 2570fps are real Power.. but I still dont understand that my .460 wby does 2500fps with 550 grain and the much bigger .500 Jeffery dont do more than 20fps with 20grain more bullet weight...
Maybe the barrel length of 26" of my .460 does this.. but do really 2" of barrel lenght do so much?

I have wondered the same -got a 460 years ago

and after many years finally got with the program and purchased a proper crf in a 505 Gibbs which shoots a tad more energy

old man Duckworth carried and shot a 460 guess he knew it had enough to get the job done

stradling
What numbers are you getting with your .505 gibbs?
barrel length?
2600+ fps with a 600 grain bullet is possible with the gibbs?
Then it start to get to Another World than the .460...

chuck375 or anyone that have a .500 Jeffery!

I was wundering about one thing..
Are you not curious about what your .500 Jeffe really have to give...? why dont try a faster powder than 4350 and slowly slowly work up until you see pressure signs and then back a bit..
I would have done that if I had enough Money to buy one
Or is the recoil to brutal?
I worked up my .460wby with the 550grain woodleigh rnsp to 2500fps with 123grains of norma 204 powder. No pressure signs but I know it was just to high because the 500 grain hornady rn start to give pressure signs with a load of 124,2grains.
It HAS to have more to give

I have done that with H4895. I get just over 2410 fps with 104g H4895. At 105g after leaving my cartridges in the sun (I was working up loads for my 270 Weatherby), I got 2530 fps, but stick extraction. The cartridges were almost too hot to touch before I chambered them. That being said, since this rifle is meant for Africa, I didn't see the possibility of a stuck case worth an extra 200 fps. I think a 570g TSX or A-Frame (or Barned Banded Solid) at 2300 fps should be enough for anything if I place my shot well.