M77man

Maybe a meaningless post but I'm annoyed that they label it a .270 when it's actually a .277. On the other hand, I am relieved that my 7mm Mag is not referred to as a .284.

Sorry if I wasted your time, but I feel better now.

Knightia

Maybe just you since no one else responded?

Isnt the .270 more a 7mm-then the 7 mm?

Maybe they should just call the .270 a 27. cal ?

Knightia

Or should i say the .270 is closer to a 7 mm- then what gun makers claim as a 7 mm?(7mm=.276 of a inch)


But calling a .270 a .277 would make more sense your right.



Inches 0.276
Millimeters 7mm






0.276
7mm
Cant find my reloading manual so not sure.... but i think thts right for what is claimed as a 7 mm.And that make it reall close to .277

Hairtrigger

Just you.
Are you anoyed that your Ford Bronco does not eat hay?

Tony Orlando and Dawn

I'm still in deep depression over the fact that a 44 magnum is actually only a "43 magnum" at best!

uncle matt

Isn't theresomething more worthy of worrying about?

Maybe like the length or number of your nose hairs?

Red Lion

If this is your biggest concern in life right now, you are doing great! I think that you should just get rid of the little ole .270 and get real rifle, like a .300 win mag or .338.

bigbulls

There are two measurements in the bore of a barrel. The groove diameter and the bore diameter. The groove diameter is the distance from one side of the bore to the other at it's widest point. The bore diameter is the distance from one side of the bore to the other at its smallest point (tops of the rifleing).

The .270 is named what it is because .277 is the groove diameter (widest diameter)of the barrel and .270 is the bore diameter (smallest diameter)of the barrel.

So take .277 inches, which is the diameterof the bullet,and subtract .0035" per side of the bore to accountfor the rifling and you get .270 inches.

7mm is called 7mm because of the same reason. The 7mm bullet is .284" whichis also thegroove diameter of the barrel. Now subtract .004" for each side of the bore to account fir the rifling and you get_______________ .276 inches or 7mm. []

This applies to most, but not all,of your center fire rifle cartridges.

Paul L Mohr

NEVER measure a muzzle loader if this bothers you. They vary quite a bit from maker to maker which is why they make different sabots.

Go to Hornady and look at the different size bullets they have for different calibers, this is pretty common actually.

Take for instance a .357 handgun will shoot .357, .38 and 9mm ammo.

Paul

idahoelkinstructor

lol, I don't think you can even strech it that far,because .429" is still a bitunder a.43". I own a .41 Mag as well as a .44 mag.Bothare Ruger Blackhawks, the .41with strong but still very save reloads is almost the .44's equal, but it comes in a bit smaller package for packing on my bowhunts for self protection.The .44 is the new special edition for 2006 Flattop and it lighter than most .44's, butif I realy want more power than that well I'll just pick up my .454 Casull.