300 win mag OAL and reamer question

[mwflydog]

Hi,

I am into my first build, have a Kreiger barrel on the way, and plan on getting an action from Northland to put together a 300 wm. First, if the mag box is 3.450 (correct me if I'm wrong on that), how long can my cartridge be and still cycle well?

Second, once I know how long my cartridge can be, do I have to take a bullet that I plan on using (190 berger vld), seat the bullet to that length, and find out how long the freebore can be so that the bullet sits within .010 of the lands? I'm just worried that I'll spend all this time getting the parts for this build, and when I take it to the gunsmith to be threaded and chambered, I'll get it back and find out that I can't get anywhere near the lands.

I think if there is an aftermarket replacement mag box that is longer like I've seen for Rem 700s and Winchesters, then I wouldn't have to worry. If they have them for savages, let me know. Or is it possible to just cut away a portion of the front of the mag box?

Any and all info to help with my anxiety here would be greatly appreciated. BTW, does everyone deal with these issues when having a new barrel chambered?

Thanks,
Matt

[dcloco]

Yep....EVERYBODY does.

Seat the bullet to the length that YOU want it to be....check if it will fit the magbox...and consult your smith.

[MatthewUSMC8791]

I'm having that exact same problem.... My 168gr BT were 1/4" to 1/8" longer than magazine. so if you want to shoot closer to the lands, then you have no choice to only single shot loading.

Im no big fan of free bore. not saying it wont shoot well, but the norm is the closer the better till you find the sweet spot.

Just My 2 cents.

[okie2]

WHY do you want to cause your self so much cost and worries.
just go buy a Marlin XL7 300 mag for $259.00.
spend the hundreds of dollars on a good scope.

[nova1194]

Buy a Marlin = Blasphemy

[okie2]

Don't knock what you don't know.
try it first before giving your opiions.

[Fjold]

Don't knock what you don't know.
try it first before giving your opiions.

I'm not going to buy a Remington 710 or 770 either, even without trying one. How is buying a Marlin going to insure that he can seat the bullets where he wants to?


Set your bullet OAL to match your magazine length and then push the bullet in .100 deeper. Tell your gunsmith to thread the blank to set the headspace off the cartridge length and throat it seperately to match your bullet length.