thinking about building a 30-338 lapua

jamie223

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might be hard on the barrel but the ballistics would be awsome, im sure it has been done before but i cant seem to find it.
 
The 300 Ultra is faster.

A 300/338 LAI would be a beat, but what a pain!
 
Yes of course all of these high performance projects will be hard on barrels. That's not at all an insurmountable objection, the per-shot cost of a barrel is usually a lot less expensive than the per-shot cost of ammo.

What are you looking for? A good long-range hunting load, or a long-range target shooting load? Do you want a flat trajectory, or minimal wind drift, or lots of on-target energy?

(it sure is fun to explore all these "what-if"s....!)

If you are interested in target shooting (i.e. wind drift is what matters, all else is secondary), one problem with .30 calibre is that it does not have any super-duper high performance target bullets made for it at this time. The heaviest good .30 cal target bullets are only 210 grains (Sierra and Berger), it would be nice if one or more of the good bullet makers finally made a proper "heavy" .30 cal target bullet (230-250 grains, with VLD-like performance). Until this happens though, you might actually be better going with a high-capacity 7mm, since it has super-duper bullets (e.g. Berger 180 VLD class).
 
There is the 220 & 240gr Sierra Matchkings in .308

Well, besides those there aren't any :p

I wonder if you could get a slow enough powder to burn effectively in such an overbore monster. Even US869 would be fast. It's be a helluva fast rig though. I wonder if it might not be too much of a good thing, particularly given the scarcity of apropriate sized actions. I hate to say it, but the 300 RUM might max out the effective case size for the .308" bore.

But by all means build it. If you hate it or it eats the barrel and makes you cranky you can easily go to a 338 L.Imp and drive 300 grainers around 3000FPS.
 
There is the 220 & 240gr Sierra Matchkings in .308

The 220 Sierra Matchking is a pretty middling bullet, and the 240 Matchking is downright mediocre. They are both high quality, well-made bullets; it's just that their aerodynamic design (nose shape and length, boattail angle and length, shank length) is nowhere near state of the art.

FWIW one of the big .416-class cases with 120-ish grains of powder (which is commercially available as the .30-.378 Weatherby), firing a 240-ish grain bullet, is not exceptionally overbore. It is 1 grain of powder for every 2 grains of bullet. A .264 Win Mag is close (60+ grains of powder, 140 grain bullet), as is a 6mmRem (50+ grains of powder, 105-ish grain bullet). A .204 Ruger is quite a bit more overbore (30 grains powder, 40 grain bullet), as is 7mmSTW (100 grains powder, 180 grain bullet).
 
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You would lose out on the high BC bullets of the 338, but the drop isn't that huge. If you had the budget you could get 177gr HV from GS bullets, with a bc of 0.638 or the 197gr SP with a BC of 0.824. Compare that to 208gr A-max (.633), 210 Berger VLD (.631), 200gr accubond (.588), sierra 210 (.619), 220 (.607) and 240gr (.647). You could push the 177 HV pretty fast out of a big cased 300, and have a good hunting load.
 
The old gunsmith here used to build a 6.5 on a 300 wheatherby.If you want loading on these wildcats pick up the two volumes of books by P.O. Ackley.I got them from Amazon.Ackley is a Wildcater and that is what he built .

Grijim
 
What makes it a 30-338 rather than being a 30-416?

The Wildcatting naming convention seems a bit odd to me (in general). As the 338 Lapua is basically a necked down 416, would not the original parent case stay in the name?

Either way, while cool, it really seems like you be dealing with diminishing returns. That's a lot of powder to not really gain anything over more conventional, already out there, cartridges.
 
The reason it would be a Lapua is that the brass is different. If you read about the developement of the Lapua, they started with 416 Rigby brass but could not get to the required velocity without pressure signs. The Rigby brass was not designed for a high pressure loading. The Lapua brass has a thicker case web and a different heat treating to make the base of the case much stronger.
 
might be hard on the barrel but the ballistics would be awsome, im sure it has been done before but i cant seem to find it.

Lapua did develop a 30 cal based on the 338 Lapua - they called it the 300 Lapua and there is info on the web about this cartridge. Hope you have fun.
 
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