Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Rifles, Bullets, Barrels and Ballistics


Reply

8mm Thread

 
LinkBack Thread Tools Display Modes
  #85  
Old 10-25-2013, 04:22 AM
Silver Member
 
Join Date: Apr 2013
Location: Norway, Buskerud
Posts: 327
Re: 8mm Thread

Quote:
Originally Posted by MontanaRifleman View Post
Bama has nothing go do with Obama, relax

It's not your sentence above I'm interested in but your opinion in something concerning the 8 mm calibres.
Here especially the "hot" ones 8 mm RM and 8 x 68S. I found the following quotation in American English: ”From 8 mm calibre upwards the rise of sectional density and penetrating capability of practical spin stabilized rifle bullets (bullets up to 5 to 5.5 calibers in length) tends to flatten out". That would mean to me that calibres with a bigger diameter than 323' won't necessarily create better characteristics than these or will hardly do. Is my conclusion correct? Thanks in advance.
Reply With Quote
  #86  
Old 10-25-2013, 07:40 AM
Platinum Member
 
Join Date: May 2008
Location: South of Canada and North of Wyoming
Posts: 5,954
Re: 8mm Thread

Quote:
Originally Posted by Varberger757 View Post
It's not your sentence above I'm interested in but your opinion in something concerning the 8 mm calibres.
Here especially the "hot" ones 8 mm RM and 8 x 68S. I found the following quotation in American English: ”From 8 mm calibre upwards the rise of sectional density and penetrating capability of practical spin stabilized rifle bullets (bullets up to 5 to 5.5 calibers in length) tends to flatten out". That would mean to me that calibres with a bigger diameter than 323' won't necessarily create better characteristics than these or will hardly do. Is my conclusion correct? Thanks in advance.
I don't know. What I do know is that when you get to about 338 cal or so it becomes difficult to make blong high BC bullets with thin jacketed lead core bullets. I.e., the difference between the350 SMK and 425 CEB
__________________
- Mark

You will never know how much it has cost my generation to preserve your freedom. I hope you make good use of it.
~ John Quincy Adams
Reply With Quote
  #87  
Old 10-25-2013, 08:46 AM
Silver Member
 
Join Date: Apr 2013
Location: Norway, Buskerud
Posts: 327
Re: 8mm Thread

Quote:
Originally Posted by MontanaRifleman View Post
I don't know. What I do know is that when you get to about 338 cal or so it becomes difficult to make blong high BC bullets with thin jacketed lead core bullets. I.e., the difference between the350 SMK and 425 CEB
Thanks for helping me! Your answer makes it quite clear to me that the diameters between 323 and 338 should represent then the "point of crystallization" for rifle calibres due to performance. One reason more to buy (a) new gun(s), 8x68S...
Reply With Quote
  #88  
Old 10-26-2013, 03:51 AM
Silver Member
 
Join Date: Apr 2013
Location: Norway, Buskerud
Posts: 327
Re: 8mm Thread

There is still hope for the great 8mms, also in the USA! See below, might be interesting and someone will be inspired by this.

The 8x68S RWS
By Chuck Hawks

Unfortunately, the 8x68S remains largely unknown in North America, although it is popular in Europe. The cartridge is based on a large, non-belted magnum case 2.658 inches in length. The rim diameter is .512 inches. The 8x68S has a rebated rim, since the body diameter just forward of the extractor groove measures a fat .524 inch. The shoulder angle is just over 14.5 degrees. The maximum cartridge overall length is 3.38 inches, so the heaviest 8mm bullets are seated pretty deep in the case. Bullet diameter is .323".
Fortunately, the sixth edition of the Hornady Handbook of Cartridge Reloading includes the 8x68S, so all of the ballistic data that follows is taken from that source. 71.0 grains of H450 can drive a 150 grain Hornady Spire Point bullet to a muzzle velocity (MV) of 2900 fps, and 82.4 grains of H450 can drive the same bullet to a MV of 3300 fps. Muzzle energy at the latter velocity would be 3628 ft. lbs.
63.8 grains of IMR 4350 powder will give a MV of 2700 fps with the Hornady 170 grain Round Nose bullet. This projectile can be driven to a MV of 3100 fps and ME of 3629 ft. lbs. with a maximum load of 72.1 grains of IMR 4350 powder.
The 220 grain Hornady Spire Point bullet can be driven to a MV of 2400 fps with 58.5 grains of IMR 4350 powder, or 2700 fps by 64.7 grains of IMR 4350. Except for thick skinned dangerous game, this load should be adequate for any large game in the world.
The Hornady technicians used RWS cases and Federal 215 primers in a Mauser 66 rifle with a 26 inch barrel for testing. In general, the performance of the 8x68S is close to what you would get if you necked a .338 Win. Mag. case down to accept standard 8mm (.323 inch) bullets.
Reply With Quote
  #89  
Old 10-26-2013, 10:27 AM
Gold Member
 
Join Date: Apr 2012
Location: California Central Cost
Posts: 734
Re: 8mm Thread

Well, I love my Mauser (Yugo) 98. All I've shot in it are handloads of 150 Speer SP. Great fun.

But

Being an endless tinkerer, Can a 98 be rechambered to 8x68S RWS or would you go strait to new barrel?
__________________
Fred Seaman
“Ask, Listen, Learn, Grow”
Reply With Quote
  #90  
Old 10-26-2013, 11:37 AM
Silver Member
 
Join Date: Apr 2013
Location: Norway, Buskerud
Posts: 327
Re: 8mm Thread

Quote:
Originally Posted by jfseaman View Post
Well, I love my Mauser (Yugo) 98. All I've shot in it are handloads of 150 Speer SP. Great fun.

But

Being an endless tinkerer, Can a 98 be rechambered to 8x68S RWS or would you go strait to new barrel?
A standard 98 action could be rechambered with the 8x68S without any issues. But the 8x68S has a big case for a lot of slowly burning powder, so a new 26' barrel is highly recommended. Twist 1 in 9,45 in for the modern bullets. Get the action trued at the same time. Since the 8x68S is a very potent round similar to the 8mm RM with a stout recoil, you are in need of a good brake. All this combined with a decent stock will give you an excellent LR rifle.

Jens
Reply With Quote
  #91  
Old 10-30-2013, 05:32 AM
Silver Member
 
Join Date: Apr 2013
Location: Norway, Buskerud
Posts: 327
Re: 8mm Thread

How about the 325 WSM in this context. Any opinions or/and comments are appreciated.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Current Poll
Do You Shoot Rifle Competition?
YES - 33.69%
764 Votes
NO - 66.31%
1,504 Vote
Total Votes: 2,268
You may not vote on this poll.

All times are GMT -5. The time now is 06:33 AM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC