In reloading for my 7mm mag and 340 mag should I full length resize everytime OR every 3-4 times and neck size in-between? These will only be fired in my guns.

You should evaluate both techniques. Generally neck sizing provides improved accuracy potential. But sometimes full length sizing will produce better results.
Longer brass life with neck sizing is a plus. More reliable cartridge feeding is the plus for full length sizing.

muck

Yankees1,



Have you tried partial-sizing as described by Bob Hagel in numerous Handloader magazine articles and in his books ?



Over-simplified, using a full-length sizing die start out with the die screwed out about one full turn from the shellholder. Turn down 1/16 turn and test in rifle chamber. Keep turning down 1/16 and checking in rifle chamber until you can close the bolt with a slight feel. Should get good brass life and reliable use for hunting.



Changes headspace from magnum belt to shoulder.



Hammer

I am with beemanbeme on this. That's the reason I keep my hunting ammo separate from Target ammo. There will be occasions when cases will need FL resizing and I don't need that to happen on a hunt. Neck sizing will reduce case working. FL resizing hardens the Brass, and can reduce its life span some.

Redneck Outdoors

I full length all of my hunting ammo and neck size my target ammo. (yes every once in a while you have to f/l the target stuff too). When I am doing load development, even for a hunting rifle, I neck size.

It's never "necessary" to full length resize your brass. It is however necessary to once in a while "bump" the shoulder back just a tad and you don't have to F/L resize to accomplish this. Jim

After the first firing, all bottlenecked cartridges, including magnums, should be spacing on the shoulder.

Once the brass is fireformed to your chamber, all you really need is neck-sizing. This will prolong the case life, allow proper head-spacing, and minimize case stretching. Plan on getting about 10 loads per case before they need a slight timming.

Mac

Yes you do need to get a neck sizing die or a "bump" die. If you neck size with a F/L die your brass will get tighter and tighter requiring more and more effort to close the bolt. When the brass gets to this point you must "bump" the shoulder back. Jim

No, you dont "need" to buy a special die to neck size. Unscrew your sizing die a turn or two and try to size a lubed case and see how much sizing you are getting. You should be able to see the result on the case neck with the top portion just a little smaller than the bottom portion. If you cant see it you should be able to measure it with a caliper. Continue to lower the sizing die until you have achieved the desired neck tension and thats about all there is to it.

I like the Stoney Point guage set to measure headspace. Maybe its just me, but I like to see numbers on my caliper dial and know that when I want to move a shoulder back 2 thousandths I can measure it and adjust my die until I'm getting that 2 thousandths, or whatever you choose to set it at.

There have been some pretty good points made here about "bumping the shoulder", brass life, etc, but one reason to FL size after 4-5 firings will be pretty apparent to you all if you take a case that has been NS 4-5 times then FL size it and turn it upside down and tap it on the bench! You just might be amazed at what come out of it! Try it and see what you get! And for all the stuff you read about BR shooters, those guys are actually not NS anyway. They are using special "bump dies" to bump the shoulder each loading. As far as dies go, I use a bunch of different makes but my favorite (and I wish they were available for all calibers) is the LEE collet dies. They do load concentric ammo! GHD

Maybe I'm misunderstanding then, because I thought a neck sizing die, like what comes in a Redding 3 die set, didn't bump the shoulder. Thats why you need the full length sizer in the set as well so when it comes to the point that you need to move the shoulder back a little bit you have a die that will perform that operation.



But if he unscrews his regular full length resizing die so that it only sizes the neck, all he would have to do in order to bump the shoulder back a little bit is screw it down in the press. Am I wrong?

I see a lot of people mentioning that they don't neck size hunting ammo. I don't either, in fact I don't neck size anything, mostly because I have several rifles in each caliber I load for.

Here is the question...

I'm now loading for a belted case, and some have told me that I risk head seperation if I FL resize everytime, and NS will mitigate that risk. Do you still only NS hunting ammo in a belted magnum? I am loading the magnum for only one rifle, so being able to transfer the ammo to another gun is no object in this case.

I agree with beemanbeme. I also full length size for my hunting loads, but not for my range calibers. They get the full treatment. For hunting loads I not only full length size but run the reloads through the action just to make sure they are okay. I guess it's a safety thing. Best wishes.

Cal - Montreal

You accomplish much the same thing with adjusting the FL die to just touch back the shoulder a tad, (.001"-.002") as you do by neck sizing with a neck die. The difference is when you FL size the case only setting the shoulder back a thou or two, is that you also reduce and partially size the area of the body near the shoulder. Some refer to the use of the FL die to setting back the shoulder only slightly as partial full sizing. Some barrels respond to accuracy with the use of one method over the other. I use both methods but have found the neck sizing only method is the most accurate in most of my rifles. I use bushing dies for neck sizing where available.

As for using neck sizing for hunting loads, I've been doing it for years with never a problem. Generally for hunting I use new brass that has been reloaded no more than once or twice but has only been neck sized and this is mostly in belted magnums. You don't start getting resistance for chambering such rounds until the third or fourth reload and in the meantime that case is exactly conforming to the chamber.

If you use dies with expanders it IS a good idea to check the "headspace" measurement or try them in the rifle before going on an expensive hunt. Expanders if not properly lubed can pull the shoulders out a bit and make chambering difficult if not impossible.

shane, I see all these posts about FL for hunting loads and I think to myself, I've been lucky for 30 years!!! All those dead deer, antelopes, mule deer, groundhogs, foxes, coyotes......boy was I lucky that the NS round even chambered! I think that if you are doing a good job of NS then there will be no problem with your belted cases either! I usually do check the chambering of a few loaded rounds from each batch. I guess all the game I will use the 7mmMag on this coming year is hoping I screwed up!!! I'm betting I didn't! GHD