30 sherman magnum

[Copper Basin]

N570 will outperform Retumbo by 100+ fps. I suspect you have a tight bore on the 28N. My shooting partner runs 78gr Retumbo for 3080 fps in his rifle with 195s. 83gr N570 was 3170 but he wanted to use the cooler burning Retumbo.

Maybe I did ream the chamber on the tighter side. I know I reamed it tight on the 28SM.

 

[highdrum]

Maybe I did ream the chamber on the tighter side. I know I reamed it tight on the 28SM.

Is your 28N a proof by chance? I've had a few bad ones as of late, so have many others. Some well known folks have sworn them off all together.

 

[Mram10us]

I get 3038fps with the 195g Berger EH and very good accuracy with it in the 28 Nosler. My one customer shoots around .3 moa with it all the time. He shoots better than I do. And he does real well out to 1055 at the range. My 28 SM goes 3167fps with the same bullet and shoots under a .5 moa. I do like the extra speed with the same barrel wear. I guess that is how best to quantify it. I have heard of worn out barrels fragmenting the 195's down range. I have not experienced that yet.

Thanks. I had no idea the sm had more capacity. I was pushing my old 28 nosler to 2998 with 195 and n570. Very accurate but not fast

 

[Rhovee]

The SM does not have more capacity. SM is about 97. 28 Nosler 102.

 

[Elk Hunter 338]

The SM does not have more capacity. SM is about 97. 28 Nosler 102.

which compute it does not

 

[Mram10us]

The SM does not have more capacity. SM is about 97. 28 Nosler 102.

97? throat design the difference? SM disregard the laws of physics? The nosler case is extremely efficient, so I am surprised the sm is over 100fps faster here. I'll have to do a good pressure test with the new 28.

 

[Elk Hunter 338]

97? throat design the difference? SM disregard the laws of physics? The nosler case is extremely efficient, so I am surprised the sm is over 100fps faster here. I'll have to do a good pressure test with the new 28.

no its the fact that they mask running over 70k +psi!!

 

[Rhovee]

I had a 30/28 Nosler that shot 86 grains H1000 for 3090 in a 26" barrel. Friend picked up a 300 Norma. Which has same capacity. 103 grains. Guess what. He shoots 86 grains H1000 with 215 at 3040. So even though case designs are completely different. They both shoot very similar powder charges. Volume is volume in my book. Sometimes you AI a cartridge to run next node up that would be to much pressure in original cartridge design. 40 degree masks pressure. Polish the chamber, Add extra on *** end of reamers, and you can run some high pressure. I like some/most of Sherman's designs and ideas. But it comes at a cost (barrel life) when running big numbers on smaller cases.

 

[Copper Basin]

Is your 28N a proof by chance? I've had a few bad ones as of late, so have many others. Some well known folks have sworn them off all together.

I have stayed away from the carbon fiber barrel. I read too many unfortunate things on heat sink with them. I am sure that is covered in another post. I am using wilsons unless I get a customer that wants a Kreiger, Benchmark or something else.

 

[Copper Basin]

I had a 30/28 Nosler that shot 86 grains H1000 for 3090 in a 26" barrel. Friend picked up a 300 Norma. Which has same capacity. 103 grains. Guess what. He shoots 86 grains H1000 with 215 at 3040. So even though case designs are completely different. They both shoot very similar powder charges. Volume is volume in my book. Sometimes you AI a cartridge to run next node up that would be to much pressure in original cartridge design. 40 degree masks pressure. Polish the chamber, Add extra on *** end of reamers, and you can run some high pressure. I like some/most of Sherman's designs and ideas. But it comes at a cost (barrel life) when running big numbers on smaller cases.

I agree with that on my 28's. Thanks again for your comments here.

 

[Copper Basin]

I never claimed case capacity on the 28 Nosler vs the 28 SM. I am only reporting my specific experience which will always differ from another. My loads and pressure is what I am seeing as I shoot these cartridges in the rifles I build.

 

[Mram10us]

I never claimed case capacity on the 28 Nosler vs the 28 SM. I am only reporting my specific experience which will always differ from another. My loads and pressure is what I am seeing as I shoot these cartridges in the rifles I build.

I'm 15 minutes from you, so we shoot in the same environmental conditions. We should see the same results. Still amazed at +150fps

 

[Lenwood901]

taggin in wanting to build a 28 sm next year

 

[Copper Basin]

I moved to Idaho Falls now. But I hunt in Copper Basin often. Usually 7300 ft and above. Just like Stanley. I would be happy to meet you sometime and setup the chrono(labradar) and let you shoot the 28sm. Not sure what part of Idaho you are in