7mm Rem Mag COL

[math teacher]

Why is the suggested overall cartridge length for the 7mm Remington Magnum 3.290" when the .264 Win. Mag., the .338 Win. Mag. and for that matter the 30-06, the .270 Win. and the 300 Win. Mag. are all 3.340"? This has never made sense to me.

 

[Clark]

I just found that out.
The magazine can take 3.34" and that is what I do for 7mmRM hunting loads.

 

[math teacher]

I didn't realize this was such a difficult question. Guess I will have to ask Remington, if anyone there remembers.

 

[Clark]

I was introduced in 1962. Someone 22 years old then would have retired 10 years ago.

I have designed many things for many companies and then things get mangled up in drafting and technical publications writing a manual, I get it back and redline it, and then they screw up the incorporation of my corrections. If you were to call one of those companies when I was still there, it is unlikely you would have got through to me, the only person who understood why I did what I did. They mangled the theory of operation that I wrote, too.

And when you ask someone why they did what they did, from the million reasons for doing anything, they will pick the one to tell you that reflects best upon their character. I think there is something in the bible about that.

What does it all mean?
They are not going to tell you it was a mistake.

 

[math teacher]

I here what you say Clark. I was just hoping someone who has been around as long as I have might have the answer.

 

[Clark]

1893 7x57mm 3.071" 51 kpsi [no belt]

1905 8x57mm 3.29" 57 kpsi [no belt]

1906 30-06 3.34" 61.2 kpsi [no belt]

1912 375 H&H 3.6" 62 kpsi

1925 300 H&H is 3.6" 54 kpsi

1940 7mm Weatherby 3.25" 65 kpsi

1948 300 Weatherby 3.56" 65 kpsi

1958 338 Win Mag 3.34" 64 kpsi

1962 7mmRemMag 3.29" 61 kpsi

1963 300 Win mag 3.34" 64 kpsi


In the 1960s Remington and Winchester are making zillions of 30-06 type rifles with 3.34" magazines.
Why did not the 7mmRemMag get the 3.34" 65 kspi registration at SAAMI?

Let me make up some answers.

1) Remington had barrels shaking off and did not yet have the right thread glue.
2) Remington only got great accuracy when touching the lands. If the reamer throats were short enough, longer handloads could fit in the magazine that would have better accuracy.
3) In 1962 Remington only had one engineer, and he was going through a divorce.
4) Bart will come back in a week and know the guy who made the decision.