seating/crimping

tomcat_blackknights

im loading for a .338 lapua and had ordered some hornady 225 grn sst's. my question is it necessary to seat the bullet on the canelure? i know this sounds like kind of a stupid question but some bullets dont even have a canelures. so in my mind what would be the issue if you didnt (assuming you are with in over all lenghth specs). the reason for this question is because i want to seat my bullet about .015" from the start of my rifling. which in this case using the sst's would put the canelure way above the top of the case.
my next question is. im debating on if and how much of a crimp i should use for this cal. i have never put a crimp on any thing else i've loaded for, but im reading that these bigger magnum rounds should have a crimp so other cartiges in the mag keep thier overall lenghth. and to build up the required pressures to maintain accuracy when using slower burning powders.

charliemeyer007

Most of my rifles I shoot for about .003. Tube feed lever gun ammo gets a good crimp. My 45-350 R Mag bolt gun gets a good crimp if I going to the magazine same with the small ring mauser 45-70.

I would let range work answer the if and how much crimp question. Mag primer and a heavy bullet ought to get the fire lit. I have in the past used duplex loads to get the powder to burn cleaner. I don't think it shot any better, but there sure weren't any logs left in the barrel.

I remember reading about one of the great white hunter's in a culling operation. He kept the mag full on the 458, replacing the round at eack shot. After ten or so shots he needed the mag. That round lock the bolt. Later investagation revieled that due to recoil the bullets were push way back in the cases.

noylj

If shooting from a magazine, you will need a crimp and the crimp should be in the cannelure. Otherwise, recoil can push the bullet into the case and you could have a big KaBoom.
If you are shooting a single-shot, then you don't need a crimp and you can adjust COL to get best accuracy.
I suppose you can use a Lee collet crimp die, if they make one for the .338 Lapua, and that will eliminate the need to crimp at the cannelure.