This may have been done before but don't know,so here it goes.
I want the .338 Lapua catridge and have a 300 win mag sedero now. The bolt face on the win mag is .532 and the case head of the lapua is .588.If you were to rebate the lapua case to fit the bolt face i have now what effect would it have on the case? I have a machinist that will turn the cases,true the action,put a competition lug on, chamber the new barrel and so on to make it as perfect as possible. I don't care about feeding problems as my 300 win mag is already a single shot due to seating out to the lands. My question is- will there be any effect on the lapua case by doing this,if any,?
Thanks in advance
Matt

Matt,

Have your machinist friend section a .338 Lapua case and then look at the case head thickness. Just about the thickest case head that I have seen and I've sectioned a lot of brass. RWS from Germany is about as heavy as Lapua and Norma is real close. American brass is pretty sad if you are just looking at this part. Jay, Idaho

You don't frig with the cases. You open the bolt face if there's enough metal to do so. Then you have to 'adjust' the extractor to fit the new case size. It's not just a matter of changing the case.

why not try the 338/300 ULTRA , you get same water capacity as 338 LM and perhaps a bit more , you can use low cost REM case and you doesn t need any bolt head modification .

you need a long action as REM700 or SAVAGE or SAKO and doesn t use the mag box , single shot only.

good shooting

DAN TEC

Your revisiting the old issue of the wisdom of converting a Rem 700 to a .338 Lapua. The one thing you are doing right is to not try and open the Rem boltface to .590. In fact, although you are creating a single shot rifle, leaving the bolt face at .532 will work although you will have to make a special Lathe tool to deepen the case rim-extractor pocket also. When you turn the rim down it will also get thicker and will have to be cut backfrom the rear. The brass is thick enough and this tool is easily made from a brazed long carbide cut off tool. If you do the math, there isn't alot of steel surrounding the chamber of a Rem 700 when converted to .338 Lapua. Some Gunsmiths like Dan Lilja in fact warn against this conversion. However, hundreds of guys have done it with the full .590 case head and a Sako extractor conversion. However, if you keep your loads reasonable, there should be no problem, other than your gonna need new brass from your buddy pretty often. Your buddy will quickly find out that this is more work than he bargained for. You are of course also creating a very unique cartridge and the resale value of the gun will be zilch. Nevertheless it will work. I personally would not do it though. Been there, done that! The best approach is to build a .338 RUM. There is nothing the .338 Lapua can do the .338 can't. I've owned both and IMHO the .338 RUM is in fact the better cartridge. You can then feed at least two down and not be stuck with a single shot.-Rob

[ 12-22-2002, 10:52: Message edited by: Robgunbuilder ]