270-300 Win Mag now feasible

Big Jake Duke

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I know that the 277 caliber bullets have been victims of their own success. There are millions of 1-10 twist barrels so bullet manufacturers have been slow to add high bc bullets for long range that would require a faster twist, believing that the market share is too small to be a vaild market. But this year- should be this summer, Berger is entering the field with a 170 gr .704 tested bc. We also have the newer Nosler LRAB 150 gr with a .625 bc.

I heard Bob Beck on Firing Line Radio Show talking about the Berger Bullets he was testing in a 270wsm. And i got the bug.

I just rebarrelled my favorite 300 win mag with a 28" #6 1-8 twist barrel in 270-300 Win Mag from Pac Nor.

I believe i will have a velocity on the 170s of close to 3300fps, the 150s a little over 3400fps. Only step is annealing and necking down a 300 win mag to .277.

Let me know what you think. I have nitrided the barrel, so im not worried about a short life .
 
Nice, the 150 ABLR is running around .569 G1. Not great, but not bad either for a 150gr... Considering the 150 Berger VLD is only like .514 G1. The 135gr SMK practically matches it at .495 and that's 15gr lighter bullet weight. That 170 ought to be sweet though!! The BC figures I've stated are all from Bryan Litz's testing as well
 
Don't forget about the Matrix 165gr .277 bullets. The listed BC is .650. Based on my experience with the 160 Matrix .264 bullet I'd bet that the listed BC is pretty close.

I have a 270 RUM that I'll get around to playing with someday that would be perfect for the 165-170 class bullets. I've run the 140 NBT over 3600 fps from the 28" barrel, so I'd call 3400+ and easy number to hit with the 165 range bullets.
 
I run a 7mm-300WM and with H1000 and a 180 Berger hitting 3130ish fps I still have a bit of room left in the case for powder. Being the 270 is a tad smaller bore you might want to see what slower powders are available to you and run them on quick load if possible to see where your case volume will be at.

Is an 8 twist the recommended twist for the new Berger? I know you can run the 165 matrix in a 10 twist.

With a Berger measured bc over .7 and muzzle velocity of 3300ish fps it would be long range hammer though!
 
It is recommended to have a faster than 1-10 for the berger. 1-8 is what is available from two sources, Pacnor being the one I chose. I also forgot to mention Daniel Smitchkos Cutting Edge Bullets that have a .590bc on a 140gr bullet. He recommends at least a 1-9 for that. 1-8 maybe more than i need, but it is what it is.

Inalso am having the barrel itrided this week and i should have it backand in the stock ready to go in two weeks. Redding makes 270-300 dies, they are already on my desk.gun)
 
Hello Feenix-

We did so well with the 270AI s that this is the next progression. Bc from 6-700 from 140-170grs . I am excited. That's what this sight is about isnt it? Dreaming things and sharing results.

For the guy who thinks it isn't a good idea, don't do it. Problem solved.
 
I'm not trying to pick on anyone, but the last I heard Berger said the 170 would be released after the 7mm 180's are caught up and the 195's are in good supply. Have things changed? After the extremely long wait on the 195's, I'm glad to hear about something else coming out.
 
Hello Feenix-

We did so well with the 270AI s that this is the next progression. Bc from 6-700 from 140-170grs . I am excited. That's what this sight is about isnt it? Dreaming things and sharing results.

For the guy who thinks it isn't a good idea, don't do it. Problem solved.

Aye Sir! I'm behind but I do have another .300 WM that will soon need re-barelling. :D
 

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Hello Feenix-

We did so well with the 270AI s that this is the next progression. Bc from 6-700 from 140-170grs . I am excited. That's what this sight is about isnt it? Dreaming things and sharing results.

For the guy who thinks it isn't a good idea, don't do it. Problem solved.

I had a 270 JDJ, an improved version of the 270 AI. Powder charges were near 70 grains. I liked it a lot. Like the AI I felt the powder capacity vs. bore diameter was near optimum.

It just seems the powder capacity vs. bore diameter in the 300 WM case would be a diminishing return with increased heat exponentially. Are you stuck on the .277's? Have you considered the 7mm Mashburn Super?
 
For the guy who thinks it isn't a good idea, don't do it. Problem solved.

lightbulbIt don't get no simpler than that!lightbulb

I have a 270 RUM that I'll get around to playing with someday that would be perfect for the 165-170 class bullets. I've run the 140 NBT over 3600 fps from the 28" barrel, so I'd call 3400+ and easy number to hit with the 165 range bullets.

More power to you, no pun intended. :D:):cool:gun)
 
Aye Sir! I'm behind but I do have another .300 WM that will soon need re-barelling. :D

That's exactly what i did. I had a win 70 i bought when i graduated hs a million years ago. That is the donor action.

585.00 chambered and fitted to the action from Pacnor, and only about a 10 week wait, which for the firearm industry is nearly an overnight service. Match grade chro moly
 

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