Long Range Hunting Online Magazine


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


Reply

338 Kahn vs 338 Lapua mag IMP

 
LinkBack Thread Tools Display Modes
  #1  
Old 12-16-2005, 07:34 PM
Platinum Member
 
Join Date: Jun 2007
Location: west of Little Rock ,Ark.
Posts: 1,271
338 Kahn vs 338 Lapua mag IMP

Pros and cons please ,

I like the idea of Lapua brass . What brass best choices for the Kahn ? Any comparisons would be great . Thanks a mill as I'm plotting to build the 338 lapua mag IMP unless you guys educate me otherwise [img]/ubbthreads/images/graemlins/grin.gif[/img], Jim
Reply With Quote
  #2  
Old 12-17-2005, 10:48 AM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,796
Re: 338 Kahn vs 338 Lapua mag IMP

Jimm,

If your shooting a 30" barreled rifle, with a 300 gr ULD or VLD bullet, from what I have seen on average, the 338 Lapua Imp will be in the 2825 fps range with top loads. The 338 Kahn will be in the mid 2900 fps range and at times some rifles will play with 3000 fps.

There are always variations, some rifles are faster, some are slower but this is about the average I have seen.

Brass to use for the Kahn is Wby 338-378 brass. It is made by Norma and is good quality brass as well. Maybe not quite up to the specs of the Lapua hulls but still about as good as you can get. I will say Lapua cases are harder and handle very top end pressures a bit better then the Norma brass.

Kirby Allen(50)

Kirby Allen(50)
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
  #3  
Old 12-17-2005, 06:19 PM
Platinum Member
 
Join Date: Jun 2007
Location: west of Little Rock ,Ark.
Posts: 1,271
Re: 338 Kahn vs 338 Lapua mag IMP

Kirby,

Thanks for your input, it is much appreciated !It seems that the difference in velocity is more than outweighed by the brass difference.
You mentioned a 30 " bbl, would a 32" give enough add'l velocity to be worthwhile? Realizing of course that the best accuracy node may be less than the max velo that can be achieved .

Thanks again , Jim
Reply With Quote
  #4  
Old 12-17-2005, 07:54 PM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,796
Re: 338 Kahn vs 338 Lapua mag IMP

Jimm,

I really recommend limiting barrel length to 30" unless you have a dedicated Heavy rifle in mind. The reason is that past 30" of barrel length, barrel mass really becomes critical in maintaining proper barrel rigidity for extreme accuracy.

In the 338 bore size, 2" of added barrel are really not that advantagous to velocity gains. You will see around 35 fps gained with the Lapua Imp and around 45 fps gained with the Kahn from 30" to 32" of barrel length.

The reason is because the 338 bore is relatively efficent even with these case capacities.

If someone wants a heavy rifle then I say go with at least a 34" barrel or even a 36" pipe but for a medium weight rifle I like to recommend a 30" barrel length and a #7 contour at very minimum for a 300 gr ULD bullet at these velocities.

Actually prefer a #8 contour to be honest but a #7 will work if weight is a concern.

For a heavy rifle, the use of a V-Block system greatly stabilizes the barrel, even if it is a 40" barrel. For a V-Block I like to use a V-Block that is at least 30% the length of the barrel.

For example, if you use a 36" barrel, 30% of that length would be 10.8". I would use an 11" V-Block.

Using this length of V-Block, you would only have 25" of unsupported barrel which translates into a VERY STIFF BARREL!!

It just depends on the type of rifle you are looking to have built and what you want to use it for as far as barrel length is concerned.

Kirby Allen(50)
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
  #5  
Old 12-18-2005, 11:01 PM
Bronze Member
 
Join Date: Dec 2004
Location: BC
Posts: 89
Re: 338 Kahn vs 338 Lapua mag IMP

How about the Weatherby Accumark bedding system is it possible to adapt it to a longer barrel a 30" or 32" in #8 contour in the 338 Kahn? Or would the whole barrel and bedding system have to be changed? I'm not fond of this zolatone stock on my Accumark, but I'm wondering how far one would have to go to make a reasonable rifle to be carried in the bush with the rifle weighing < 11lbs without scope? Right now I'm just curious as I just got my Mark IV rings so I can mount my scope and start shooting. It's been a long journey for this rifle and I re-joined the range last weekend and went to their Christmas party.

As well I received my grizzly/buffalo bullets from Richard Friday, 300-325 gr tappered jacket bonded core mag tip flat base, quite a mounthful. And I've taslked to a Buffalo rancher north of Edmonton who wants to thin his herd. I may be going there in late January or February. It's not really a hunt in that he will tell me where they are, but the price is right $500/buffalo and I didn't get to go hunting this year... [img]/ubbthreads/images/graemlins/frown.gif[/img]
Reply With Quote
  #6  
Old 12-19-2005, 09:24 AM
Platinum Member
 
Join Date: Nov 2005
Location: Texas
Posts: 1,844
Re: 338 Kahn vs 338 Lapua mag IMP

I don't have any pics but SG&Y finished my 338 Lapua Ack Imp about a month ago and I have fire formed the brass and have some loaded to try but have not gotten out to the ranch to shoot it yet. Mine started as a 30-378 and now has a Broughton tube with the SG&Y brake which takes all of the punch out of the rifle! I did not even have to use the PAST when braking in the barrel and fire forming. I ordered the reamer from Dave Kiff at PT&D so if you want to have one built Speedy has the reamer and I have never gotten a rifle from Speedy and Stick yet that would not shoot lights out! [img]/ubbthreads/images/graemlins/cool.gif[/img]
__________________
The Truth Is Not Always Good For Business!!
Reply With Quote
  #7  
Old 12-19-2005, 10:09 AM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,796
Re: 338 Kahn vs 338 Lapua mag IMP

Alremkin,

I place the Wby MkV in the same class as all the other factory receivers when recommending barrel length and mass. Again, I would not recommend over a 30" barrel without a special bedding system being used.

Those 325 gr FB bullets are impressive for sure. I picked up a few when I was up visiting Richard. Will be trying them in my 338 Kahn and 338 AM(when I get that BAT receiver!!)

One thing to rememeber. Anytime you increase bullet weight, or velocity or bullet length, the barrel will be strained more as the bullet passes through the bore.

I still say 30" is the longest I could recommend to ensure good accuracy with bullets in these weight and length ranges.

The Buffalo cull should be a good time. LOTS of bullet testing data on that one!!

Let us know how they perform.

Kirby Allen(50)
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: 338 Kahn vs 338 Lapua mag IMP
Thread Thread Starter Forum Replies Last Post
338 Kugla Kahn Redding Dies (NIB) wiljen Reloading Equipment and Components 3 04-08-2011 02:58 PM
WTB: .338 Kahn, .338-378 WBY sample cases...... mindcrime Rifles, Bullets, Barrels and Ballistics 0 02-26-2011 01:59 PM
Testing different powders in the 338 Kahn... Fiftydriver Reloading 1 06-12-2006 08:18 PM
crows with a 338 Kahn RDM416 Long Range Hunting & Shooting 9 03-13-2006 07:59 PM
Wildcats and the Kahn at 1 mile plus.... Fiftydriver Rifles, Bullets, Barrels and Ballistics 21 03-24-2005 06:08 AM

Current Poll
Have You Ever Backpack Hunted?
YES - 62.45%
1,071 Vote
NO - 37.55%
644 Votes
Total Votes: 1,715
You may not vote on this poll.

All times are GMT -5. The time now is 05:50 PM.


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