338-300 Win Mag

[thesheepdog]

The parent to the 26 Nosler is the 7mm RUM
The parent to the 7mm Rum is the 404 Jefferies

The 404 Jefferies begot:
RUM
WSM
WSSM
SAUM

I think Ruger SM, Dakota, some Lazzeroni and some Allen all had origins in the bloodline.

The 375 H&H begot:
Almost every belted magnum design with a .532 bolt face.

Ah so the Noslers are like the 330 Dakota and such...based off the Jeffrey.

I ordered a 338-300 Reamer and am sending this with my Bartlein to my smith. Gonna have it throated to the 300gr bergers as a backup to my edge. Stay tuned.

 

[FEENIX]

Ah so the Noslers are like the 330 Dakota and such...based off the Jeffrey.

I ordered a 338-300 Reamer and am sending this with my Bartlein to my smith. Gonna have it throated to the 300gr bergers as a backup to my edge. Stay tuned.

What a coincidence, I too am interested and was running some numbers last week. What twist and groove did you decide on?

 

[thesheepdog]

What a coincidence, I too am interested and was running some numbers last week. What twist and groove did you decide on?

My Bartlein is a 1:9.3 twist. Not sure what finished length I'm going with.
Got my reamer from JGS. They have them in stock.

 

[FEENIX]

My Bartlein is a 1:9.3 twist. Not sure what finished length I'm going with.
Got my reamer from JGS. They have them in stock.

Cool, thanks! Keep us posted.

 

[Lefty7mmstw]

tagging in... I've got a #1 in 338 win that is rather boring... 2900 fps with a 225ab or hdy though.

 

[jskmtd]

What velocity do you think you will get with the 300 grain bergers?
Jon

 

[thesheepdog]

What velocity do you think you will get with the 300 grain bergers?
Jon

2700. I will post my results when I get some loads going.

 

[Cold Trigger Finger]

I considered it many times. Would give about a 5 grain increase in powder capacity. How long is your barrel? IMO 2700 fps is optimistic with less than a 28" barrel. Is your action 06 length or 375 length?
I agree with the plethora of 300 Win mag brass you would be able to find brass for ever. It will be interesting no doubt. !!!!

 

[thesheepdog]

I considered it many times. Would give about a 5 grain increase in powder capacity. How long is your barrel? IMO 2700 fps is optimistic with less than a 28" barrel. Is your action 06 length or 375 length?
I agree with the plethora of 300 Win mag brass you would be able to find brass for ever. It will be interesting no doubt. !!!!

I'm using a 7mm Mag Action. I haven't quite decided on barrel length. I do know for sure that I'm going to throat the barrel long for the Bergers. This will allow me to use the AICS CIP magazines and still have a long OAL of around 3.8ish.

 

[Deleted member 46119]

Sounds like a fun project.

IMO A 28" barrel should get you to the 2700fps range.

Have you made a dummy round yet?

 

[thesheepdog]

Sounds like a fun project.

IMO A 28" barrel should get you to the 2700fps range.

Have you made a dummy round yet?

I don't have a dummy yet. Want to help me there?

 

[Deleted member 46119]

I don't have a dummy yet. Want to help me there?

What bullet?

I don't have a 300 Win Mag die but I can short stroke it in a 338 Win Mag. I have to check some dimensions to make sure I don't alter the shoulder angles or diameters.

You have already ordered a reamer so I have no worries there, just a 'model'.

 

[Cold Trigger Finger]

With a 3.8" oal you should be able to, providing a long enough barrel. That will make for an awesome rifle. . Getting the most from the least powder burned. !! gun)
I have settled on 338 for my elr rifle and I don't want a Lapua so I'm very interested in your project.

 

[FEENIX]

Always nice to see that OP has LRH members overwhelming support and interest in his project.