Thread: 300wm... seating bullets long... by design

So... I have been thinking about a change to a 300 magnum and the rifle of choice at the moment is available in 300WM and 338 LM... same action and mag for both calibers.

I do not want a 338.... but I like shooting longer ranges with higher BC projectiles.

I imagine when it is time for a barrel change, I could consider a change to 300 PRC with the same bolt face as the 300WM, however a question for the smarter experienced ones out there...

Because it is a long action, the only limiting factor to the 300WM seating depth is the ogive to rifling distance/contact. Is it therefore possible that the rifling lands could be reamed a little to create a little more ogive clearance, bullets seated further out, use powder charges and high BC heavier projectiles that match the PRC loads and see similar performance to the 300PRC?

Posting here is the first step... next will be chats with bonifide experts if no one here points out obvious errors with my reasoning.

Looks like you need to go down the MK 248 Mod 1 route:

Some reading
https://www.americanrifleman.org/con...-mk-248-mod-1/

PDF spec sheet:
https://usarmorment.com/pdf/300WM_load%20data.pdf

Not simply a matter of 'plug and play' your rifle chamber may need some work to extend the throat (or just shoot it more )

Yes, it's possible. Gunsmiths have what's called throating reamers for exactly this.

@LBD - what's the rifle you're contemplating?

I am quite keen on the TRG42 standard, not the A1 or M10.

Yes I am a little concerned about the slow twist rate, but as I alluded to, that is only a barrel change away to correct if it is a problem. All reports are that it shoots 215gn pills stable without a problem.

caberslash... thanks for the links

The 215 bergers have a fairly long nose on them so even with a standard chamber there isnt a lot of bullet left in the case. From memory I was out over 3.6 in oal with a jump still. Speed wise in a 26in barrel I was over 2900fps.

buy the 300 norma mag on here.