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338x7.62x39 improved? or 338x 300 Savage Improved?

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26 January 2015, 02:30
Big Wonderful Wyoming
338x7.62x39 improved? or 338x 300 Savage Improved?
I have been kicking the idea of a 338 caliber rifle that would feed with 300 grain Sierra Match kings out of a 308 AICS magazine.

To shoot those same bullets supressed, and have good impact velocity to maybe 300 yards.

I want a ackley shoulder, minimum body taper, and at least a caliber length neck.

What say you oh god's of the wildcat world?
26 January 2015, 03:14
Idaho Sharpshooter
Look at SSK's URL. The 338 PPC is what you are most likely thinking.

To get deer killing power at 300yds, I would think the 338 BR or the 1 5/8ths inch BRL would be a better choice.

You know the trajectory is going to be like hitting a golf ball with a 5 iron at 300yds...?
26 January 2015, 06:53
Big Wonderful Wyoming
Looking for just a simple neck up and improved shoulder.

I need it to fit in .308 AICS magazines. It's for a bolt rifle.

Might end up being a 338-300 Savage to work correctly.
26 January 2015, 22:45
bartsche
quote:
Originally posted by Big Wonderful Wyoming:
I have been kicking the idea of a 338 caliber rifle that would feed with 300 grain Sierra Match kings out of a 308 AICS magazine.


What is the maximum cartridge length in a .308 AICS magazine? Confused roger


Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..
28 January 2015, 08:14
Big Wonderful Wyoming
I don't actually have a 308 magazine here. I am out of town until Mid-Feb.
28 January 2015, 20:16
butchlambert
Remember that they have different bolt sizes or simply the diameter of the case heads are different. Don't know why, but the 300 Savage parent case would cause less problems and allow you more case capacity.
28 January 2015, 20:17
theback40
If you run a .308 case into a 300 sav die, you have a nice long necked, sharp shouldered case. What about that opened to .338?
28 January 2015, 23:41
bartsche
quote:
Originally posted by theback40:
If you run a .308 case into a 300 sav die, you have a nice long necked, sharp shouldered case. What about that opened to .338?

tu2Applied that same thinking to my 6.5 RJB ; fast twist deep throat. Roll Eyes roger beer


Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..
29 January 2015, 01:55
dpcd
I must be missing something. A 7.62x39 in .338 caliber seems quite useless to me. Why would you want a .338 bullet to go that slow?
29 January 2015, 02:10
butchlambert
Maybe a 1000FPS round to use with a can?
29 January 2015, 02:55
dpcd
Those ain't allowed in this state so I want the maximum noise possible.
01 February 2015, 06:03
Big Wonderful Wyoming
quote:
Originally posted by theback40:
If you run a .308 case into a 300 sav die, you have a nice long necked, sharp shouldered case. What about that opened to .338?


I think an AI version of just that would be awesome.

Thanks for the idea.

308 brass is dirt cheap, once fired 308 is cheaper still. Even lake city is cheap.
01 February 2015, 09:03
boom stick
338-6.5x47 AkA 8.5x47 with the right powder should be a good subsonic to supersonic cart.


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

*we band of 45-70ers* (Founder)
Single Shot Shooters Society S.S.S.S. (Founder)
02 February 2015, 09:28
Big Wonderful Wyoming
Boomstick,

Sounds good, I'll order a reamer and dies from PTG in a few months.

Other irons in the fire.
02 February 2015, 11:22
boom stick
The good brass should help with accuracy. I think it would be pretty sweet with the lighter bullets for supersonic hunting as well. The fatter heavier 338 bullets should rack up tight groups with good wind bucking abilities to boot. I liken it to a 30 BR on steroids.



Changing the 6 to an 8 on the head stamp should be easy for a 8.5x47 wildcat.




577 BME 3"500 KILL ALL 358 GREMLIN 404-375

*we band of 45-70ers* (Founder)
Single Shot Shooters Society S.S.S.S. (Founder)
02 February 2015, 18:45
richj
a 338 fed is 2.8 oal so is a 308win
02 February 2015, 18:49
richj
never mind.. longer bullets

quote:
Originally posted by richj:
a 338 fed is 2.8 oal so is a 308win

03 February 2015, 07:44
Big Wonderful Wyoming
Dammit!

This is really coming together.

Trying to find a 1 in 8 338 barrel in stock someplace.
03 February 2015, 08:19
boom stick
Who has the quick load program to figure out what powder to get that 300 grain bullets with a 2.8 oal to 1,050 fps? Also curious how fast the 338 Barnes 165 grain bullets would go. 2,600 fps?


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

*we band of 45-70ers* (Founder)
Single Shot Shooters Society S.S.S.S. (Founder)
03 February 2015, 08:25
Idaho Sharpshooter
dpcd,

this case makes a great alternative as a door breaker for PD's to the 300BLK. I have a friend with a select-fire AK in 338x39. It's fun to shoot as long as somebody else is standing behind a Dillon 650...
08 February 2015, 22:35
boom stick
.9567"
1.8433"
3.6811"
2.7244"
What do these numbers mean?
3.6811" is the 338 Lapua oal
2.7244" is the 338 Lapua case length
Subtract these and you get..... Yup you guessed it .9567"
2.8"-.9567 is 1.8433"
The 6.5x47 case is 1.85". Yes seven thou longer than 1.843". A good case for this project.
Question is, when you neck up 6.5x47 brass, what the average length of the case will be?
Do we want to keep the official 1.85" length and let the brass grow to max length of 2.85" after necking up? This mini 338 Lapua is pretty sweet imho. The neck length is pretty good and could even be shortened to 1.8".


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

*we band of 45-70ers* (Founder)
Single Shot Shooters Society S.S.S.S. (Founder)
10 February 2015, 20:25
jpl
If you're shopping for mag-fed .338s for fun you should consider .338 WSSM. Like a stubby 338 Federal AI. If it's anything like my 7mm WSSM it will feed great. Little point into a big chamber.

~51gr powder capacity and around 3100ftlbs muzzle energy.

Example: .338 225s at 2520fps

Should be easy to down-load for subsonic too. The aftermarket has AICS style mags for Magnum cases allowing up to ±2.975" OALs MAX. Or modify steel .308 AICS mags to fit fat cases and remove teh front plate for ~2.975 max OAL.

Seems that there's a law of conservation of energy. Given a bore diameter you should be able to work up loads between different weight projectiles to the same ME given there's no encroachment on the case capacity by seating a bullet deep. So with a data point of 225gr at 2520fps and ~3150ftlbs ME

You should be able to get the 165gr Barnes up to about 2950fps and a 300gr up to about 2150fps