I want to build a .338 Lapua on Remington action. I want to put it in an A5 McMillan stock. I was just wondering what has to be done to the action/bolt to accomadate the Lapua? I was also wondering what barrel length/contour I should go with?
Action mods depend on what bullet you want to shoot if you put 'em down in the mag, center feed Wyatt box is comonly used. Inside length is 3.8" for the 700 LA. Single feed is normally the way the 300gr SMK is used, it eats up serious case capacity if it isn't.
Bolt face mods are straight forward. Open up and sleeve bolt ring to fill Rem extractor recess, open up to Lapua diameter, reface boltface, install Sako extractor, bevel outside edge of extractor for clearance so it snaps over rim and your done with the necessities. Bush firing pin, set pin depth with Tubb speedlock pin assembly if you wish.
Modify bolt stop to feed from the mag, remove a tad over .100" from it, got to take a little off of it to let the bolt come back to the rear of the new mag box that sets further to the rear. Mill out the tang at the rear of the box the forward guard screw on the ADL's thread into so the box sets in, bed in nut to stock if using an ADL stock. Rebed floorplate and that's it.
You may have to open the lips on the Wyatt box for the Lapua to push down through, Chris or George would know.
I'd send it to them and let them do it anyway.
Barrel tennon on the M70 is 1", M700 is 1 1/16" dia [img]images/icons/wink.gif[/img], so I'd use the 700, JMO tho. I've got data sheets for numerous M70's done in 30/378 Wby by a smith up here, he was killed in a car accident and the sheets and serial numbers were with the Oehler 43 when I bought it from his widow. So both actions are used, just most of them are 700's.
Axe: I currently have a 7mm based on the .338 Lapua Mag case and, as Brent stated above, you will need to open up the bolt face, put in the Sako extractor and machine the action to accept the .338 case so that it will fit in the magazine. I am a single shot guy myself, but the Wyatt box will be necessary. If you wish to use the Speed-Lock pin though, you will need an older model 700 as the pin will not work with the "J lock" system on the newer Rem. bolts. Other than this, you shouldn't have any problems undertaking this project. As a matter of fact, I am going to convert the 7mm back to the .338 Lapua as soon as I am finished doing the load research for the bbl I am using now as it will be about time for a new bbl! All being said and done; you should have a mighty fine rifle once you finish here! Let me know how it turns out!
What ya doing over here Mike? Anyway, will we see you in Texas?
Build a bunch of Remmy Lapuas. Brent got most of it except for a few minor details.
We (GA) have a new M16 style extractor for it, much better than the Sako. And I feed it either with a Sunny Hill FP using a Weatherby mag box or the HS Detach. Both will work in an A5. Another good way is putting it into an AI chassis.
A few other mod are made to the receiver, opening up rails, ejection port etc....
Usually use a 30-06 action, then don't have to bush the bolt face.
Couple questions -
BTW, good idea using the 30-06 boltface.
The HS Detachable mag - What's the max loaded OAL you can get with those?
What's the cost of another mag for it?
They hold 3 don't they?
M-16 style - I've heard they work well, what's the major difference between them, and the advantage?
Weatherby box - One smith that used to do a bunch of these chamberings before he was killed in the car accident, Dana Cambell of Mountain Rifles Inc. used the Weatherby box and modified them, my smith Dave has a hanfull or two left that he had already modified. I think they're thicker steel than the Wyatt.
I haven't had the port milled open on mine yet, but it needs it done.
I think I'll use the HS drop box in my 338 Imp version.