new Mag actions & LA Same ?

[Willoughby]

other than bolt face -are the new Mag actions & LA Same ?
is the opening in the bottom of the receiver same or longer on Magnum actions ?
could I switch barrels from 300wm -3006 on a new 114 by just changing bolt face & DBM ?

[efm77]

Yep. As far as I know, the openings in the receiver are cut the same. Just a bolt face and mag change are all you'll need.

[stangfish]

I thought they built one long enough for the 338LM. A BA action or something. I realy dont know a damn thing about it. Just throwing some crap on the wall to see if it sticks. Or was it the LRH action where the ejection window is smaller.

[efm77]

The action for the 338 Lapua is the same length and dimensions as the other long actions. However, it is heat treated differently to make it stronger, has a smaller ejection port to make it stiffer, thicker locking lug recesses, and thicker locking lugs to help prevent lug set back from the huge case head. It's also a large barrel shank. Oh and they lengthened the magazine to fit the cartridges as well. But with a standard long action, be it a 30-06 or a 338 win mag, they're the same action. Just different magazine and bolt face.

[Gmac5]

If they do all of that to the 338 lap, what did they do to the 308 rem ultra mag ? Its sammi pressure is more than lapua ,rebated rim, near same usable case cc. And early ones were small thread and stainless! I havent heard of any going boom bang yes ,boom no.
Gary

[nsaqam]

The .300 RUM has a much smaller base and rim diameter than the .338 Lapua does.
Since bolt thrust is a function of the internal area of the web/casehead portion of the case the bolt thrust is higher on the Lapua than it is on the RUM.
Not to mention the extra metal removed from the locking lugs to accommodate the huge .588" rim of the Lapua.

[Gmac5]

I would have to agree to disagree with you bolt thrust /pressure 338 rem ultra ,rebated rim u didnt forget about internal surface area being equal did u

[Gmac5]

338 lap has much thicker case base walls than rem ultr ,go ahead cot some apart ,i havnt had one yet asthin as rem ultra & u r correct but rem ultra has rebated rim

[efm77]

Doesn't matter. It still has to do with the exterior surface area of the bolt head. Even if the interior dimensions are smaller, that pressure is still being exerted over a larger area with the Lapua which puts more stress on the bolt head/locking lugs. They have been built on regular actions and ended up having problems with lug set back. Ask Sharpshooter about his experiences in building them to test them out. He said in a thread on here that it wasn't a good idea and explained why. I'll see if I can find the thread. He built one on a regular long action, small shank. He had lug set back and the chamber was temporarily swelling during firing and springing back due to the chamber walls being too thin which caused cases to stick. The RUM is smaller in diameter so the chamber walls can be made a little thicker and has a rebated head which reduces the amount of bolt thrust with the other benefit of it fitting a regular magnum bolt face. If it was safe enough to do on a regular long action then Savage would have done it. The RUM is about the biggest that can be safely put in a regular action.

[efm77]

http://savageshooters.com/SavageForum/index.php/topic,36123.0.html

Here it is. You can read Sharpshooter's observations on this one.