270-300 Win Mag now feasible

[Buckammo]

This is an awesome thread. Thank you for all the information. I will have a .270/7mm Rem Mag ready to test in about three weeks. Hopefully, I will be able to contribute something useful.
John

 

[Longtooth32]

I have

IMR 4350, 7828 and 7977

Hodgdon H1000, Retumbo, US869

Alliant 23, 25, 26

Once I get some brass fireformed I will begin working on a load ladder probably starting with 7828 and the 130 scirocco.

Your want to only shoot the "normal weight" 270s got me to thinking…

I could not find any of BJD's 140gr Cutting Edge in stock…but I do have SST 140s and 130s on my shelf…

The only baseline that I have for the SSTs is the 150gr SST @3380fps pushed by 76grs of H1000. So according to Hodgdon…I can add one grain of H1000 for each negative 10 grains of bullet weight…

So…I loaded up some rounds up to 81 grs of H1000… without powder compression, but it was close…

I hope to chronograph these speedsters tomorrow….

I sure do not hope that I melt the tips...

 

[Big Jake Duke]

In southern California, the closest thing we get to real weather are the Santa Anas. These are major winds from 20-70mph. So at the range today conditions were less than ideal. This was the best group i had with my H1000 load. Velocity was 3260.

Not good, but about 300% better than the Bergers with US869.

These are the 170s

 

[Big Jake Duke]

Then the winds calmed down, the sky opened up I heard a voice from above say- Hey Dummy, try Retumbo.

Unfortunately i had only loaded a small ladder. Who knew?

This is where i'll be spending my time from now on!

 

[Big Jake Duke]

75gr Retumbo. 3225.

 

[270DT]

BJD that's looking good! I am going to the range Friday and then soon after that I can start contributing some data!

 

[dwm]

Longtooth32 stop posting pictures of those 270Weatherby cases, they are starting to look really interesting.

Those are standard 270Weatherby cases right, not 270/300Weatherby wildcats ...?

 

[Longtooth32]

Longtooth32 stop posting pictures of those 270Weatherby cases, they are starting to look really interesting.

Those are standard 270Weatherby cases right, not 270/300Weatherby wildcats ...?

Just a standard throated (which I believe is .36") 270 Wby with a 28", 1-9, Benchmark barrel on the Mark V action.

 

[270DT]

Finally got to the range today and sent 20 rounds downrange to fire form brass for the 270-300WM. My load was 72 grains of IMR 7828 with Fed 215s. I was just shooting some Speer 130 grain HotCors as I was really just playing and using el cheapo bullets for this. It showed absolutely no signs of pressure or detonation issues. I did not have my chronograph with me.

This load shot so good I am going to save it for a reduced hunting load, pretty much stayed an inch or less at 100 yards. I will chronograph it next time. After the first few shots it definitely got some attention as the other guys at the range said it definitely has a unique report/crack/boom whatever you want to call it. It didn't take long for the barrel to heat up and I was extra slow shooting. Took me about 3.5 hours to fire 20 rounds.

Now I can start working with the bullets I really would like to have for hunting. I will keep you guys posted.

 

[Longtooth32]

Finally got to the range today and sent 20 rounds downrange to fire form brass for the 270-300WM. My load was 72 grains of IMR 7828 with Fed 215s. I was just shooting some Speer 130 grain HotCors as I was really just playing and using el cheapo bullets for this. It showed absolutely no signs of pressure or detonation issues. I did not have my chronograph with me.

This load shot so good I am going to save it for a reduced hunting load, pretty much stayed an inch or less at 100 yards. I will chronograph it next time. After the first few shots it definitely got some attention as the other guys at the range said it definitely has a unique report/crack/boom whatever you want to call it. It didn't take long for the barrel to heat up and I was extra slow shooting. Took me about 3.5 hours to fire 20 rounds.

Now I can start working with the bullets I really would like to have for hunting. I will keep you guys posted.

If it is any help…my 150 Bergers were doing 3280fps @ 72grs of 7828SSC…and it was a very accurate load...

 

[Longtooth32]

75gr Retumbo. 3225.

Good shooting...that is where I got my best groups and best ES...around 75-76grs of Retumbo...

 

[Big Jake Duke]

Good shooting...that is where I got my best groups and best ES...around 75-76grs of Retumbo...

Ill do a ladder around this and see if there are any improvements to be found.

Something i found interesting is that the seating depth was the same as the us869 load that was a 3-4 inch disaster. So is it seating depth or the right powder vibration?

In this case it looks like i stumbled upon the correct combo.

 

[CogburnR]

This may be interesting reading for you.

Optimal Barrel Time Paper

 

[270DT]

I was just curious if anyone had run the 270-300wm through quick load to see what data it came out with? I just need to buy it myself as I could use it for two other rifles I have. I know it's not an exact science but I feel a little more confident than the method I have been using so far of pin the tail on a powder and hope I picked the right starting load.