338 thunder project

[goodgrouper]

Roy,

I have taken the 338 ultra mag and reduced the case taper from something like .027" on the standard to .012" and made the reamer .547" wide in the web area to give about .002" clearance as the web on the brass measures .545. This should totally eliminate the "belly-out" look that drive me crazy. It doesn't really hurt anything, it is just unsightly.

Then I gave the shoulder a 40 degree angle to put the hottest part of the expanding gases into the side of the opposing neck wall instead of into the throat. Brass is expendable, barrel steel not. /ubbthreads/images/graemlins/wink.gif

THen I made the neck dimension .367 which gives me .013" neck wall thickness after turning the high side off the brass and it will run a good neck/chamber clearance.

Then 7mmrhb and I squared the case heads and took that new measurement into account but it made insignificant difference.

I then had the reamer throated so the 250 grain Lapua Scenar could be seated to fit the Rem box magazine and cycle well. I really lucked out here because as it turned out, the 225 grain Accubonds have nearly identical ogives and shapes so if the Scenars don't work on phone books like I hope, I can switch right over to the Accubonds without any trouble. I know they work! /ubbthreads/images/graemlins/wink.gif

OK, then I ordered a drop in Mcmillan Lazzeroni sporter stock in marble finish and had them inlet for a larger size barrel. THen I got on the horn to Mike Degerness (very cool guy by the way, I highly recommend talking to him)at Advanced Barrel Systems and had him order a Rock 5r 338 1-10" 27" blank. He is then going to wrap it in his custom heat transfering carbon fiber blend and attach his titanium muzzle brake which weighs in at something like 3 ounces. He will start the wrap an extra inch ahead of normal in front of the recoil lug so I will be able to set the barrel back and rechamber several times if need be.

Dies are being made by a machinist friend of mine who uses a single point boring method to make the necessary "squeeze" in the body for a hunting rifle. He will also counterbore the top half so Redding bushings can be utilized to size the neck. Very crafty this guy is I tell you!

Then I have a Holland pinned recoil lug ordered so it can be switch-barreled for the .284 wildcat my uncle just had Kirby do. I also have a Sako extractor kit, a Holland bolt handle, and a Jewell trigger on it's way for it.

Kirby is going to assemble it all to my Rem 700 action he has already been shipped.

Riding atop this beast will of course be a Leupold long range 6.5-20x50 sitting in Burris signature rings with the 10 minute inserts installed for 1500 yard plus elk hunting.

If my calculations are correct, a stiff dose of 95 grains of Rl25 should propel the 250 grain Lapua bullet at 3100-3200 and about 92-95 grains of RL22 should move the 225 accubonds at 3300-3400 hopefully. This beast should be capable of 5200 ft-lbs of muzzle energy and have enough umphh to break the shoulder blade of an elk at around 1 mile plus.
Have to wait and see what accuracy will be. /ubbthreads/images/graemlins/wink.gif It might not shoot good enough to kill elk at 100 yards if my luck holds out. /ubbthreads/images/graemlins/shocked.gif
Anyway, it should be interesting.

 

[JD338]

goodgrouper,

Should be an interesting project! Sounds like what you have done is "AI" the 338 RUM case. I have a M700 LSS in 338 RUM and I love it. I killed a black bear with it this fall using the 210 gr PT at 3200 fps. Bang flop.
Good luck with the 338 Thunder project.

Regards,

JD338

 

[Guest]

hmmm.. I question this...

1 mile is what 1760 yards. You do all this work to a 338 RUM case and then choose a morginal bullet for Elk at that distance. Yes the AB's are good bullets but by your numbers and my calculations... you only have..

1256 fps and 775 ft. lbs at 1750 yards...and loosing everything realativly fast because at 1700 yards you were at 1282 fps and 822 ft. lbs.

I seriously doubt your gonna get 3200-3300 from 92-95 grs of powder but maybe with another 3" of barrel.

Why wouldn't you shoot the 300 gr SMK.. at 2750 fps? You then have at least 1175 ft lbs of energy at 1750 yards...that is more suitable for Elk.

Now I am not sure how much Elk hunting you've done but you are boarder line whitetail killing energy. Even the 250 gr Lapua Bullet has better energy at that distance. And you are choosing a powder that is temp sensitive so your load work up at 60* will more than likely not give you the same velocity at 30* and will be much slower and this creates even more problems...

I'd like to see you reconsider your choices. As I said given your numbers ( with some error due to whatever elevations you are hunting) ( I inputed 5000 asl ) .. you are marginal to say the least. Surely the Majestic Elk deserve a bit more respect than whitetail killing energy...

Back to the drawing board???

 

[goodgrouper]

Thanks. Glad to hear the 210's worked.
I kinda did the same thing to the 338 ultra that Shehane did to the 6.5-.284.

 

[goodgrouper]

Uhh, no. The numbers I calculated were for the 250 grain Lapua bullet. It will kill at 1 mile if the construction is good. I will test it first rest assured.

Pouncing again?
Ric, we agreed to not communicate with each other anymore. I was serious about it, please leave me alone and respect our agreement. THank you politely.

 

[Guest]

Chill there Dude...
I am not seeking you out, but , remember. I do assist hunters every year. I am a licensed guide in Wyo. I do guide individuals that seek out lr shots. I do make sure they have the right equipment and / or required capabilites to quickly and efficiently kill their intened target!!!
I simply am thinking of doing a 338 project myself and have done my own research. I saw your post and was interested in what project you were doing. After reading your data I recognized some immediate red flags!!! You sir, are marginal with what you are doing and the bullets you choose. If it were anyone else on the board I would have raised the same issues!
You cannot expect me to avoid you all together when there are similar issue we deal with. Relax a bit there GG. If someone else can contribute contradictory data to what I have said and helps me ( or you ) see there is fault or correctness/incorrectness in what you are doing. Then we both win by learning something.

Again I simply identified a few red flags from what my data shows to what you have posted.

that is it, nothing more nothing less. Wasn't you who said we are here to learn?

 

[Buffalobob]

GG
If the scenar will hang together, it has great numbers way past a mile. I wouldn't have believed it if I hadn't run all of those calculations earlier. It will be interesting to see how things work out.

 

[sewwhat89]

[ QUOTE ]
hmmm.. I question this...
1256 fps and 775 ft. lbs at 1750 yards...and loosing everything realativly fast because at 1700 yards you were at 1282 fps and 822 ft. lbs.


[/ QUOTE ]

Not to call the kettle black or anything, but I think you are gravely mistaken to say that an additional 400 ft/lbs goes from insufficient to sufficient.

That is much less than the difference between a 45 Colt and 454 Casull, and both will cleanly take a bull elk at 50 yards, with the same bullet, and break both shoulders. This is not apples and oranges, so save that argument. It all revolves around bullet construction.

 

[goodgrouper]

Thanks buffalobob.
The Scenars are quite impressive indeed. With a bc of .675 and a speed of just 3050, they will produce the power to accomplish what I want. Even the accubonds with a bc of .550 at 3200 will still break the shoulder blade at around a mile! YOu know from emails we have sent each other that I have found about 800 ftlbs will get the job done (from our calculations, it is actually 700 something but I like to round up) and these bullets will both easily accomplish it according to Exbal, Infinity, Ballistic explorer, and PS workbench. The elk I shot last January at 820 yards was killed with the Accubonds, and I loaded up some 7mm 160 accubonds for a friend of mine last fall and he killed a great bull at 25 yards and the mushroom looked identical to mine. Accubonds obviously work at all ranges! I would have to look back at my post, but I think my impact energy on the elk was nearing the 800 ft/lb mark but was a touch higher.
The key as you mention with the Scenars is construction. When I sawed a few 300 mk's and Scenars and accubonds awhile back, I was really impressed with them all but the Scenars looked like they would mushroom just a touch more at long range thanks to the huge hollow point. I don't know if I will actually take a shot at 1 mile, but 1500 should be realistic at some point if the conditions permit!

If all else fails, the Moag will be handy to have around. It launches the 300 grain MK at 3100 for an impressive crunch! /ubbthreads/images/graemlins/wink.gif

 

[Shawn Carlock]

GG,

Being a 338 fan myself I believe that your barking up the right tree. While the energy is getting a little on the low side, energy is not the end all be all. The specs you talk about 250 @ 3150 should give you about 800 ft/lb or so at a mile. This is about the same a a 30-06 165 gr @ 700 yards and I know several people and one in particular who have taken elk at a distance that the energy was around 800 ft/lb. Elk are a tough animal but it does not take much to shoot clear through one if you are not "boning" them so to speak. I do beleave that as we all know it is mostly about the shooter. I hope your new projects is "hummer".

 

[Guest]

please check you data, there are issues that are questionable.

 

[Dave King]

GG and Ric

Make and/or stick to a non-aggression agreement!

Ethics is not a topic for discussion on this board.

Bickering, please cease all bickering or the/these threads will be altered/deleted.

 

[Guest]

Dave,

With all due respect. Do you see my point? I simply addressed some issues that are legitimate. Are they not? Not picking on GG at all but I have projects I am considering for a .338 and I have some issues with my own date etc. If it were anyone elses post besides GG's would there be a need of a mod to interject?

I am not attempting to engange in an ethics argument here but data is data no? If anything there can actually be something learned here not argued over. I didn't act aggressively, and I qualified my intial post by saying I have my own project I'm thinking about.

I'll cease this discussion, but there are definite legitimate marginal issues here. Why we can't talk about them is beyond me.

 

[IDAHO PREACHER]

I am interested in the 338 thunder and the project and what capabilities it has, from 50 yards to 1 mile or even further. Ethics are up to the indiviual and his abilities to shoot. I would like to keep it to that subject. By the way Ric, don't need to ever call anyone a kid! Thanks GG I would love to know more of your project. Preacher