195 grain 7mm Berger - How Much Cartridge Will it Need?

[Edd]

Santa Clause, the Tooth Fairy, the Easter Bunny, and Berger 195 gr 7mm Bullets.

 

[MudRunner2005]

Santa Clause, the Tooth Fairy, the Easter Bunny, and Berger 195 gr 7mm Bullets.

Pretty much how I feel about it...

 

[joeycoates]

I must be looking at something incorrectly on the calculator then?

Twist Rate Stability Calculator


Use this form to determine your gyroscopic stability factor (SG) based on the Miller Twist Rule

Input Parameters
Caliber .284
Bullet Weight 195 Grains
Bullet Length 1.5
Barrel Twist 9 Inches/Turn
Muzzle Velocity 3000
Temperature 59
Altitude 4500 Feet



SG = 2.01

Not saying that you will not need a 8.5 or 8 twist to stabilize, I am just asking.

Is there any reason not to run that fast of a twist rate, i.e. would it make lighter bullets come apart easier at higher MV's due to the increased RPM's leaving the barrel?

 

[Edd]

I must be looking at something incorrectly on the calculator then?

Twist Rate Stability Calculator


Use this form to determine your gyroscopic stability factor (SG) based on the Miller Twist Rule

Input Parameters
Caliber .284
Bullet Weight 195 Grains
Bullet Length 1.5
Barrel Twist 9 Inches/Turn
Muzzle Velocity 3000
Temperature 59
Altitude 4500 Feet



SG = 2.01

Not saying that you will not need a 8.5 or 8 twist to stabilize, I am just asking.

Is there any reason not to run that fast of a twist rate, i.e. would it make lighter bullets come apart easier at higher MV's due to the increased RPM's leaving the barrel?

In your other post you said any altitude. To me, any altitude would include sea level.
Using 4500 feet will make some difference. The other difference is, you are not using the correct bullet length. The correct length is 1.637".

 

[joeycoates]

Yea, I had to guess on length as I have not seen the actual length anywhere. I know that it will make a difference.

 

[sendero72]

You may want to give the 190 gr Matrix a try.

 

[Deleted member 46119]

7mm/26 Nosler!

Well that's my story and I'm sticking to it.

IMHO a STW, WSM, Dakota, Allen, 7mm/375 Ruger or a 284/7mm/26 Nosler is probably where you want to go.

I don't think a 284 Win or AI or a 280 Rem or AI will hunt the way you would want.

 

[deadlift]

I've ran the matrix 190's out of my 280 AI @ 2550 fps and they stabilized at sea level in a 9" twist. Now I'm running the 7mm Dakota and matrix 190's @ 3041 in our 9 twist. No issues at all.
Chris
Benchmark Barrels

 

[MudRunner2005]

I've ran the matrix 190's out of my 280 AI @ 2550 fps and they stabilized at sea level in a 9" twist. Now I'm running the 7mm Dakota and matrix 190's @ 3041 in our 9 twist. No issues at all.
Chris
Benchmark Barrels

Good info to know! Thanks Chris.

 

[bigngreen]

I've been shooting the 215 Berger out of a 308 and it's really been an eye opener to what a heavy high BC bullet can bring to chamberings we would not usually consider. I've always though that a 7mm-338 Norma mag or the 7mm-300 win would be the way I'd go for the 195 but I think the 7mm-08 or the 284 may be just as fun and deliver a serious amount of hunting capability for very, very low input!!

 

[Swamplord]

Not a big 7mm fan but have considered the option of a 7 mm version of my 6.5 PRO wildcat in the event of the mystical 195's, it has a neck length of .347" and opening the neck would make it slightly longer which is a good thing, measured case capacity is 105 gr h20 in the 6.5 , the 7 mm version will get you 7mm Rum ballistics easily with less powder, shorter case so you can seat the bullet out for effective use of case capacity, coupled with a .350" long neck for bullet support and help tame throat erosion .
I wonder if I can convince John at Whiskey Three Precision to make me a batch of 200 gr Tac's with the rebated boat tail and aluminum tip !

I think a call to Kiff is in order first thing Monday, I may have convinced myself to give a 7mm a shot ....

 

[MudRunner2005]

Hey Pro, just for fun, you got any Berger 180 Hybrids laying around? If so, neck up one of your 6.5 brass and stuff a 180 Hybrid in it and post up a pic of the dummy round. Don't be skurred of the 7's... You should be pleasantly impressed with the upgrade, if you like 6.5's.

I bet that would be nasty...

Do the Pro cases still use a .540" bolt face?

 

[Swamplord]

Mud

I do not have any 180 Bergers but have a few leftover 160 gr Barnes X bullets from the late 90's
I loaded a bunch of them for my fathers 7mm Rem Mag for hunting deer on Kodiak and he ended up taking almost all Alaskan big game with that bullet... ..... (how many of you remember buying them for $20 in K-Mart ? )

Since you asked .... I made up a 7mm PRO (on left in pic) by necking up my 6.5 PRO.............
and a 28 Nosler from a new 26 Nosler case for comparison..... ( COAL on both is 3.340" )
the case head is the same as 338 Lapua Magnum , I just miked the Norma brass & it came in a .584"

I don't hate the 7mm's, have been around them all my life and the 7mm RM was the third cartridge I started loading in the late 80's due to it's popularity in my extended family, I just noticed that my 30'06 and especially the 300 Win Mag hit with more authority and as a kid that was ingrained hard and I can't seem to shake it off, other than that there is absolutely nothing wrong with the 7mm cal., most impressive bc's and form factor on 'em Berger bullets

 

[MudRunner2005]

I bet the 7mm PRO blows the .28 Nosler away...