Lets talk the SA and 338 bullets

if you want greater powder capacity you will likely need a very good action to build off of. The Fatso (lapua based) would probably give you the edge your looking for otherwize you might look at a Lazzeroni or a possibly a gibbs shortened. However you would be looking at a lot of case prep needed, very expensive brass. Also when you go for the action that you need to handle some of these cartridges you will be heavier than you would have been building an edge and I would guess the performance would be slightly less.

I would be curious to see what the gain would be to go to a 338-270 wsm If that would really work to neck up that much???
 
I am not exactly sure just how much length you can get away with. But on Ammoguide it says the 338-300WSM has 79.9 grains of water capacity.

The 338 Ruger compact magnum only has 69.4.

I think that if one could determine what max length possible for short action you might be able to get very creative in forming your own brass, but I doubt you will get much better than the 300wsm as parent cartridge....

The Wyatt is too long but it's parent cartidge is the 416 Rigby. I little more diameter. Perhaps shortening the 416 to the maximum length and necking it to 338. But may be more than action can handle. Thats why I will probably never wildcat something original. I know enough to be dangerous, not enough to actually know what my limits are:)
 
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I started browsing the Ammoguide options and stumbled across the 416 GNR.

It is designed to work off the wsm action.

This looks pretty cool. Probably could neck it down to 338 also.

From the description:

Parent case for the .416 B&M is the .300 Remington Ultra Magnum, shortened and neck-expanded to .416 caliber.

SPECIFICATIONS
Bullet Diameter:
.416 in.
Max Overall Length:
2.995 in.
Rifling Twist:
1-in-14.0 in.
Rifling Lands:
6
Case Capacity (est):
90.2 gr. water
Primer Size:
.210 in.

NOMINAL PERFORMANCE
Bullet Weight:
400 gr
Muzzle Velocity:
2200 fps
Muzzle Energy:
4300 ft-lbs
 
You will have many more options if you go with a single shot compared to a mag feed. I'm looking at the 338 Norma Improved for my next build.
 
Good info guys I have been milling this over for a while. I was under the impression that the 300 wsm would give me more capasitty then the 270 wsm would?

I have a FN wsm action already and that would be the base for the build if I made the decsion to go ahead with something like this.
 
Good info guys I have been milling this over for a while. I was under the impression that the 300 wsm would give me more capasitty then the 270 wsm would?

I have a FN wsm action already and that would be the base for the build if I made the decsion to go ahead with something like this.

What about the 325wsm? You may not have to overwork the necks that way. I dont know the first thing about wildcatting, but I would think it would be easier to go from 8mm(325wsm) to 338 than it would be to go from .277 to 338 wouldnt it?
 
I mis spoke earlier. I meant the 338-7mmwsm. since the 7mm wsm is slightly longer than the 300 wsm which the 270 and the 325wsm are based off of.
 
Hay guys I want too build a 338 on a short action. I am hopeing there is an option out there I have not explored. I was thinking 338-300 wsm but I think there must be a case that will give me more power. What do you know that I dont?

Jon

If it were me I would consider a 325 WSM or to get a better bullet selection, neck it up
to 338.

The 300/338 is popular but you have to neck up .030 and you gain nothing in case capacity.

The 7mm WSM has a little more case capacity because of the shoulder being further forward
but necking would be very difficult and the necks would be very thin when finished sizing.

The WSM is about the most powerful cartrige in a short action and nothing has to be done
to it (Body has very little taper and the shoulder is already 35o (37 to 40 is about max).

Factory brass is available and if you decide on a 325 factory ammo is available and the bullet
selection has improved in the past few years with weights from 150 to 250 grains. there is a
200 grain Accubond that is ideal for long range hunting/shooting .

If you single load the WSMs you can seat the bullets out, giving you a little more case capacity.

J E CUSTOM
 
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