30 sherman magnum

Yes, thanks Chris! I finally got to shoot my ladder this morning too, and experienced very similar data. Same components, very similar seating BTO 2.918 (0.070" jump). It was 74 Deg when I started and about 80 by the end. Station psi 23.80, about 6K' and RH 34%. I started at 79.0/ 3127 fps and ended at 82.0/ 3250, but I'm running 28" tube. My only issue was I was piercing primers at 82.0, but no other signs of psi. And AIs have history of this with the huge firing pins, so thinking about trying some thicker cupped CCI 250s and also just staying closer to 81.0 with the F215s. More data shortly.
 
Yes, thanks Chris! I finally got to shoot my ladder this morning too, and experienced very similar data. Same components, very similar seating BTO 2.918 (0.070" jump). It was 74 Deg when I started and about 80 by the end. Station psi 23.80, about 6K' and RH 34%. I started at 79.0/ 3127 fps and ended at 82.0/ 3250, but I'm running 28" tube. My only issue was I was piercing primers at 82.0, but no other signs of psi. And AIs have history of this with the huge firing pins, so thinking about trying some thicker cupped CCI 250s and also just staying closer to 81.0 with the F215s. More data shortly.
Good work and nice to have more confirmation!
 
As far as groups, you can see same hole first 3 at 79.0, lowest SD was 81.1 at 5.8, but not a great group (could have pulled one). Last group at 82.0/ 3250, same hole, bust pierced primers too.
 

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Here's a 79.0 grain primer, and you can see the pin's hammering the primer pretty hard with deep indentation.
 

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The speed possible with these Sherman's and the long barrel life got me thinking in another direction. I used JBM ballistics to reverse engineer a MV for 28SM to get me to 1800 FPS at 1300 yards. Berger has said that is the minimum speed necessary for there Elite Hunters to provide terminal expansion. Knowing I will not take a shot a 1300 yards and that my range is normally 900 yards and in where I hunt, I thought I would run some numbers. At 3150fps you hit 1800fps at 1475 yards. Given my inputs of temp, station pressure, twist rate and so on, the program gave me that result. 3150fps is a load that will be easy on pressure and the rifle. These cartridges are crazy fast and chasing speed for something I won't do anyway is overkill. This is my new approach on the 30SM as well. I will continue to run the 6.5 SST II close to the hot side. That round is too much fun. This is just something that I thought about doing. Good luck all.
 
The speed possible with these Sherman's and the long barrel life got me thinking in another direction. I used JBM ballistics to reverse engineer a MV for 28SM to get me to 1800 FPS at 1300 yards. Berger has said that is the minimum speed necessary for there Elite Hunters to provide terminal expansion. Knowing I will not take a shot a 1300 yards and that my range is normally 900 yards and in where I hunt, I thought I would run some numbers. At 3150fps you hit 1800fps at 1475 yards. Given my inputs of temp, station pressure, twist rate and so on, the program gave me that result. 3150fps is a load that will be easy on pressure and the rifle. These cartridges are crazy fast and chasing speed for something I won't do anyway is overkill. This is my new approach on the 30SM as well. I will continue to run the 6.5 SST II close to the hot side. That round is too much fun. This is just something that I thought about doing. Good luck all.
Good info and good thought,👍
 
New Load work with IMR 8133 today and the 28SM. Back to the wide speed node. 78.5g 8133 and 79.5g 8133 ran the same speed and close on the es, 24 and 27. Both clocked at 3056. The 78.5g load was shot at 5702 elev and the 79.5 was at 7100 elev. Temps were close at 52 and 46. 80g of 8133 got me to 3089 fps but a 34 es. No pressure or ejection issues except for the first shot at 80g. It was sticky coming out but bolt lift was fine. the 79.5g load shot a 1.5" group at 539 and the 80g shot a 4" group. I think 805g could be my max and will try it next week along with US 869. I hope this information is useful and it is only what works in my rifle. I will stop powder experimenting with US 869 since I can't find any RE-33. My load with N570 is the best so far.
 
Rich,
Any testing of LRT powder in your 30 Sherman Magnum? Browsed this Thread and may have missed it?
If not here, a link to another thread with LRT powder?

I'm currently running N570 in my 8x68S cases (slightly different cartridge than your 30SM), but interested in any LRT data in your cartridge, or any of your prior but similar cartridge versions.
Thanks
 
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Rich,
Any testing of LRT powder in your 30 Sherman Magnum? Browsed this Thread and may have missed it?
If not here, a link to another thread with LRT powder?

I'm currently running N570 in my 8x68S cases (slightly different cartridge than your 30SM), but interested in any LRT data in your cartridge, or any of your prior but similar cartridge versions.
Thanks
Hi Paul. I shot it a little in my 30/375 S.I. but cant say I TESTED it.
It loads about like RL33 for charge and velocity. Its very dense and a ball powder so it holds a lot.
 
I think this may have been addressed in the original thread but I don't see it here, after scrolling all 20 pages. Can the 30 SM reamer cleanup a standard 300 PRC chamber?
 
I think this may have been addressed in the original thread but I don't see it here, after scrolling all 20 pages. Can the 30 SM reamer cleanup a standard 300 PRC chamber?
I doubt it will do anything with neck dimensions, but Rich does take more taper out of his cases and steepens the shoulder angle.... so at least that portion would get "cleaned up."
I'm curious now too.
 
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