The Perfert 338 Lapua Mag Build

[Willys]

Lapua long 3.90 throat = 2900 fps, Lapua ai = 3000 fps with 30" barrel , rl33.

If you reload and willing to wait for dies no reason not to go ai.

Could go with a Smith that has ai dies on hand.

 

[Coyote Shadow Tracker]

Were building our own rifles so wait times from a gunsmith is not a factor. We have two builds going on right now. Took us a while to decide on the 6mm BR and 6.5 X 284. We talk about what we are looking for in a cartridge first then go to the drawing board. Right now we have all the reloading components for these builds. Now to start the build. We have top of the line gunsmithing machinery and equipment. Just need the rifle components (barrel, chassis, action), which we have ready available access to. It's one of those things where we are in no rush. Have factory rifles and several builds already for hunting critters to dangerous game, PRS & "F" class. Everything now is a work in progress to stay busy and have something to look forward too. On this ELR build will most likely start purchasing reloading components as soon as we make a definite decision. It is down to the 338LM and the 338Ai. Not sure if the Ai is "Worth it" , maybe not the right wording, to fireform for the amount of extra 100 or so FPS. I was looking at this because of the time involved and using two primers for the first shot, but that is only once to fireform.
Just a question to the group. If a company designs a cartridge and goes through all the R&D to have the best preformance, why are cartridges then "Ackley Improved". Most of the time by just changing the shoulder for example 30 to 40 degrees. Why wouldn't the manufacture do that to begin with?
Thanks
Len & Jill

 

[Willys]

Military and mfg 1st requirement is cartridge chambers smoothly from Magazine. 40 degree shoulder is not what you would start with if this is primary requirement.

 

[surgeon260]

Why wouldn't the manufacture do that to begin with?

My guess why Ackley chambers aren't "standard" is that it has to do with feeding smoothness and feeding reliability. Cases with 40 deg shoulders and minimum taper don't feed as smoothly and any deviation from a perfectly clean chamber is more noticeable. This isn't really a concern for a target shooter.

Not sure if the Ai is "Worth it" , maybe not the right wording, to fireform for the amount of extra 100 or so FPS. I was looking at this because of the time involved and using two primers for the first shot, but that is only once to fireform.

In my experience shooting 4 different Ackley cartridges, the first fireforming shot is not wasted. Fireforming loads are typically extremely precise. I don't see much if any difference in precision between virgin brass and fireformed brass. Ackley also gives you cases that never need trimming, which is awesome.

 

[Coyote Shadow Tracker]

Military and mfg 1st requirement is cartridge chambers smoothly from Magazine. 40 degree shoulder is not what you would start with if this is primary requirement.

Exactly from a Military standpoint for a manufacture, but there are only a few cartridges used by the military. Look at how many cartridges (non military) have been Ackley Improved. Why would shooters go with a cartridge that has chambering issues? Just for some more performance?

 

[Coyote Shadow Tracker]

My guess why Ackley chambers aren't "standard" is that it has to do with feeding smoothness and feeding reliability. Cases with 40 deg shoulders and minimum taper don't feed as smoothly and any deviation from a perfectly clean chamber is more noticeable. This isn't really a concern for a target shooter.



In my experience shooting 4 different Ackley cartridges, the first fireforming shot is not wasted. Fireforming loads are typically extremely precise. I don't see much if any difference in precision between virgin brass and fireformed brass. Ackley also gives you cases that never need trimming, which is awesome.

Ok just trying to get all the correct information the we can. I was refering to wasting a shot (primer/powder/time) when fireforming with COW. I
Thanks for this info. Most likely will go with a 338Ai

 

[Barehandlineman11]

I typically buy cheap primers and fire form with pistol powder so not much waste other then time. And ive done fire forming on a barrel break in. Works both ways

 

[JJMoody]

If someone doesn't buy this one soon, I'll finally consider it mine.... and name it
338 edge+P. Should push a 300 to around 2950 with h1000
BAT single shot
31" Rock creek
Manners T2a
Huber 2 stage.....

 

[sp6x6]

Moodys is the real deal.Ask this lots of countries had the lapua and are now going in some part to the norma,Which i have 2,that by most respects has less performance.If you ai it its probably a lapua.

 

[Rum Man]

If someone doesn't buy this one soon, I'll finally consider it mine.... and name it
338 edge+P. Should push a 300 to around 2950 with h1000
BAT single shot
31" Rock creek
Manners T2a
Huber 2 stage.....

I'm wondering if 3050 or 3100 ft.per.sec is possible with Re-33 powder ? Then do I really need 3100 ft.per.sec?
I have shot my 29" Kreiger 338 Edge pushing a 300 gr berger at 2849 ft.per.sec out to 3027 yards . I have 325 min.of elevation available is the extra 200 ft.per.sec really needed ??
Maybe I better +p my Edge to see ??
Any thoughts Guys ?? Is it worth it to have Shawn Carlock do his Magic to the chamber ??

Rum Man

 

[JJMoody]

I'm sure other powders can offer more velocity. I'm pretty well stocked on retumbo and h1000, so I'd run either of those, but looking around, seems like 570 and 33 are pretty well established for the round. I've heard of velocities up to 3150+ (Not sure how much I believe that, but it sounds fun and I like to get western now and then). I try to limit how many different powders I'm burning and stay with the super temp stable stuff. As far as the +P goes..... my philosophy on hand load-only cartridges and a ground-up build for ELR...

"If you're going to New York, don't get off in Chicago."
Might as well go for it.

I'm trying really hard to not spend a lot more money on optics. I've looked at the Ivey mounts as well as Charlie Tarac and wedge prism stuff..

 

[sp6x6]

my friend was telling me or buddy wise running fire form out of his ai and 90 was in the 2800 range with retumbo.In my norma I was max at 90.5,had sd-11,2812v, with 300otm

 

[H82MISS]

tagging in here

 

[Painless300]

My dream 338 LM
Surgeon action
Surgeon BTM
Terry Cross KMW Stock - heavy fill
Heavy Palma/MTU 29" 1-9 tw take your pick on barrels - Krieger, Bartlein, Benchmark, Proof etc...
TT Trigger
TBAC Suppressor
Berger 300gr OTM
Tangent Theta 5-25x56 Gen 3 ret
Hawkins Precision rings