7MM Mag OAL question

[kblack583]

Loading rifle cartridges for first time and have run into something the books don't answer for my 7MM Mag.

Using Hornady 139g SST's. Brass is new and trimmed to 2.490".

Hornady data calls OAL of 3.290" but the longest I can go and just get to the cannelure is 3.260".  Do I ignore the cannelure and just load to the 3.290 OAL or is 3.255" - 3.260" OAL using the cannelure the way to go?

Thanks

Kevin

[cwlongshot]

There are a couple limitations to look at when considering the OAL of a given cartridge.
 MOST of the time your magazine or box will limit the legnth long before you get into any issues.
 If you are loading for a SS rifle, you have more latitude. I really like STONY POINTS GAUGE for cartridge OAL. For accuracy I like a bullet to be 5-7 thousands off the rifling. With the Stony point tool its cake to get it exact.

cannelures are there for a couple reasons.
 If its a box mag and the firearm has recoil it can push the bullets deeper into the case, reducing capacity and increasing pressures. cannelures are also useful/mandatory in tube magazines for the same reasons as above.
 BUT SS rifles have no use for cannelures. Using them in rifles is certainly NOT mandatory.
 The last place they are needed is magnum centerfire pistol calibers. Here they keep the bullets IN the cases as well as help with uniform powder burning. That infinitesimal extra bit of resistance before the bullet is pushed from the case can sometimes make a good load GREAT!!

 Good luck,
 CW

[cal sibley]

Your data doesn't sound quite right to me.  I have a Remington 700BDL in 7mm Rem. Mag. and load my bullets out a bit further than that with no problems.  For example I load the Sierra 168gr. HPBT Match out to 3.420",
and that's not its maximm length.  Best wishes.

Cal - Montreal