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deep throat on 7mm Rem Mag--low velocity?

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11 February 2005, 03:00
friarmeier
deep throat on 7mm Rem Mag--low velocity?
Hello everyone!

I need a bit of guidance: last season I worked up some loads for my father's Savage 110 (circa 1965) 7mm Rem Mag. His primary interest was accuracy, as he hunts only whitetail; also, his shoulder was broken in a car accident a number of years ago, and is now a bit sensitive to recoil.

That said, I put together a load using Nos CT ballistic tips, and after a little tinkering, was shooting moa. My father was more than pleased with this.

Here's the interesting part. After running them through a chrony, we found they were in the neighborhood of 2700 fps (150 gr.). I don't have the load data in front of me at the moment, but the Nosler manual (#5) indicated 3100ish. The chrony was giving us anticipated velocties on other known rifles/loads that day, so that eliminates one variable.

Now, it's not that I'm a velocity freak, and the fact that it was coming out a bit slower didn't bother my dad at all, with the shoulder bit. But out of curiosity, I called the Nosler tech, and the first thing he asked was, "does the gun have a long throat?"

His recommendation was that I could slowly step-up the powder charge (I was already at the book max load).

Anyone have a similar experience?

P.s. the throat is so long, the magazine is the limiting factor.

Many thanks,

friar


Our liberties we prize, and our rights we will maintain.
11 February 2005, 05:24
fredj338
All rifles are diff., chmbers, throats bore dia., bore smoothness, all affect velocity. If the rifle is older & has been shot alot, the throat could be washed out. Weatherby uses long throats to keep pressure a bit lower while sueezing a bit more vel. out. The Nosler tech. is right, just step up 1/2gr @ a time unril you reach the vel. you want or pressure signs start to show.


LIFE IS NOT A SPECTATOR'S SPORT!
11 February 2005, 05:26
elkhunter
I have a Savage 116 with a long throat. I load the max of 79 gr of R22 in my 300 Win Mag with a 165 grain Hornady IB. This is the hottest load I have seen in any manual (3200 FPS). It shoots 100 FPS faster than, that in my rifle with no signs of pressure. This is very stange because I have a 2" muzzle break on the gun, giving me an effective barrel length of 22". I can't explain it, but I'm not complaining.
11 February 2005, 19:12
sdgunslinger
In fact , the Savage 7mag rifles from back in those years were routinely cut with quite a bit longer throat than many other brands. You will likely need more powder to equal the speed from a shorter throated rifle . Work your way up slowly and use a chono to check your results......
11 February 2005, 20:56
friarmeier
Thanks for the comments fellas! Big Grin

Sdgunslinger, any idea why Savage cut them longer?

The gun itself is beautiful--too bad Savage doesn't make them with that kind of stock any more--just like a Browning White Gold, but with an oil finish.

Thanks again,

friar


Our liberties we prize, and our rights we will maintain.
12 February 2005, 10:32
WestCoaster
My older mod. Tikka is the same... long throat and magazine/clip. I found when I 1st started loading it that it was about 230 fps slower than my current loading manuals called for at that powder charge. It usually takes about 4 more grains to match their velocities.
12 February 2005, 17:52
Rob1SG
My old Ruger M77R was the same but I had shot out the barrel.Replaced the barrel and am getting exactly what the Nosler Man. indicates. They sell Savage barrels that you can just screw in with the proper head space guage or have a GSmith do it for a reasonable price. Good luck either way
12 February 2005, 19:30
El Deguello
"It seems very difficult to impress most reloaders with the fact that every rifle is an individual, and what proves to be a maximum load in one may be quite mild in another, and vice versa." Bob Hagel, GAME LOADS AND PRACTICAL BALLISTICS FOR THE AMERICAN HUNTER, 1977

Always work them up for EVERY GUN!!


"Bitte, trinks du nicht das Wasser. Dahin haben die Kuhen gesheissen."
12 February 2005, 21:49
friarmeier
Thanks for the good reminder, ElD--you can be sure I'll "go slow" (which is good advice on any number of fronts, yes? Smiler


Our liberties we prize, and our rights we will maintain.