Medium 338's vs. Big 338's

[Long Time Long Ranger]

I recieved several messages when I posted on another thread some of my thoughts concerning best use for the medium size 338's like the 338 RUM, 338-300 RUM and standard 338 Lapua. These thoughts were based on average long range hunting situations where a guy needs to be on the money first shot. I stated that in my opinion these size cartridges are best with 225 and 250 grain bullets for the ranges they are best suited at long range hunting. Which inside those ranges the lighter bullets have far less drop and not much difference in wind. They do not push the 300 grain bullets fast enough to increase that range very much. To do that a guy needs a big 338. All the messages basically stated how popular some of these cartridges were for long range hunting. I have been doing this a long time and these are the reasons I shoot big 338's off the 378 wby, 416 rigby and Excalibur cases. I think they are self explanatory. I used 2800 fps for the three medium sized ones and 3100 fps for the big 338's. I know somebody is going to say I get 2850 or a little more in theirs but there are just as many that get 3150-3200 in the big 338's. But these are averages.

Extreme long range hunting is extremely difficult and you must put every odd in your favor to do it succesfully every time. Once you get beyond 1000 yards you need every possible fps you can get to help you out. Both these velocities have a zero of 2" high at 100 yards which is a common zero for me.

300 SMK at 2800 fps and 5000 feet elevation where I live and 10 mph wind.
1000 yards, drop 233.8", windage 41.6", 1882 fps, 16" drop in 25 yards.
1200 yards, 376.7", 62.6", 1722 fps, 20.5" drop in 25 yards.
1500 yards, 682.2", 104.8", 1501 fps, 30" drop in 25 yards.

300 SMK at 3100 fps same as above
1000 yards, 181.3" drop, 35.7" windage, 2123 fps, 12" drop in 25 yards.
1200 yards, 293.8", 53.6", 1951 fps, 16" drop in 25 yards.
1500 yards, 533.2", 89.3", 1709 fps, 23.5" drop in 25 yards.

My point was if you plan on shooting much over 1000 yards you need to look at a big 338. Out to that range the lighter bullets in the medium size 338's have much flatter trajectories and better on game performance than the 300 SMK. Windage is not enough of a factor to 1000 yards to make that much difference. That is why all my medium size 338's are all loaded with the lighter bullets and the big 338's that can get a 300 grainer near or over 3100 fps are loaded with the 300's.

Look closely at the most important factor of hitting big game at extreme range. Judjing the range correctly! With the medium size 338's at 1200 yards your dropping 20.5" every 25 yards. At 1500 yards your dropping 30" every 25 yards! How many rangefinders can hit accurately within 10 yards at that range. Now say you have 15 fps deviation from your input velocity and add another 5" to your problem here or 9" at 1500 yards. That means you have got to hit your range within about 12 yards just to hit an elk decent at 1200 and maybe 6-8 yards at 1500 yards. That means with everything else perfect. Now say your gun groups 10" at 1200 yards and your shot is at the bottom or top of that group. Now you see why every fps and every inch is important in extreme range hunting. I have done it and I know.

Now with a big 338 at 3100 fps. It drops 83" less at 1200 yards and 150" less at 1500 yards. windage is 9" and 15" less. It drops 16" every 25 yards at 1200 and 23.5" every 25 yards at 1500 yards. 15 fps change shot to shot is 3" at 1200 yards and 6" at 1500 yards. That gives you a few more precious critical yards to be off your mark and still hit your animal. Maybe about a 25% better chance. That is what I was talking about.

 

[Edd]

So what is your #1 bullet choice for a 338 Lapua for 600 - 1000 yd hunting?

 

[Long Time Long Ranger]

My 338 Lapua that gets the most hunting is a lightweight carry rifle with a 26" barrel. It is excellent as a light carry rifle for any game. To reduce recoil in the light rifle and make it more pleasant for my wife to shoot I have loaded the 225 accubond in it for the past few years. It will easily take any game to 1000 yards. My wife took her monster muley with it this year at 516 yards and just destroyed it. My best accuracy load for it is 3320 fps and I can do that with three different powders. Best accuracy load with a 300 grain bullet is just over 2800 fps. Comparing the 225 at 3320 and the 300 at 2820 at 5000 feet elevation and a zero of 2.5" high at 100 yards the 225 shoots 43" flatter at 900 yards with 6" more wind drift. At 1000 yards the 225 shoots 53" flatter with 7" more wind drift. Not enough wind drift to make a difference but the flatter trajectory makes quite a difference shooting mil dots.

If anyone plans on shooting beyond 1000 yards with the Lapua it is best to go with the highest BC's and not the 225 although the 225 will easily kill game at 1200 yards out of the Lapua. With this class of cartridge I am going to try the cutting edge 225 grain bc .640 and 250 grain bc .720 in the future. That 252 with a .720 bc will greatly extend the range of the lapua and RUM's. I can push the 250 SMK at 3140 fps out of my lapua. If the cutting edge bullets work out they could be special at the ranges most anyone could ever kill an animal. With heavy rifles that can tame the recoil of the 300 grainers they are fun to shoot. But the recoil difference in a light carry rifle is tremendous going to the 300 grainers from say a 225 grain. Recoil is accuracy for most people. As recoil goes up, accuracy goes down. That is fact.

The 225 accubond has better on game performance than the 300 SMK.

I forgot to put the other data in here. Again same 5000 feet elevation and 2.5" high zero at 100 yards. At 800 yards the 225 accubond is in the 15" elk kill zone for 47 yards vs 36 yards for the 300 SMK. The 300 SMK has 4" less wind drift. At 1000 yards the 225 accubond is in the 15" kill zone for 31 yards vs. the 300 SMK in the kill zone for 25 yards. The 300 SMK has 7" less wind drift.

So I get 11 more yards in the kill zone with the 225 accubond and 4" more wind drift at 800 yards. Or nearly a 25% better chance in the kill zone with only 4" wind difference in a 10 mph wind. Less recoil and a premium hunting bullet.

As I stated earlier if your shooting over 1000 yards the 300 grainers look better the further out you go.

 

[wyobill]

I totaly agree with you LTLR well stated.

 

[Long Time Long Ranger]

In extreme range hunting your bullet is dropping through the kill zone of your target for a very short distance. It is best to choose a cartridge and a bullet that will have you in that kill zone for the maximum range to give you a better opportunity for a kill. That bullet needs to be one that will give you the best opportunity for a kill. The largest caliber heaviest bullet you can keep in the kill zone for the longest distance and be able to shoot it accurately from a shoulder fired weapon that is light enough to carry hunting with you is best.

When punching paper or shooting rocks at extreme range you can walk it in to the target and then pepper it with about anything that is accurate. Hunting is different and you need a rifle that will give you the best opportunity with the first shot. Using my data above at 1200 yards the medium size 338's pass through a 15" elk size kill zone for 18 yards. Assuming your rifle shoots a ten inch group at that distance which averages out velocity spread you are in the kill zone for 12 yards with every bullet. With a big 338 like I use long range you are in the kill zone for 23 1/2 yards or 15 1/2 yards with every bullet from a ten inch group. That gives you a 23% better chance at getting your elk first shot. Actually more when you consider the 9" less wind drift.

When choosing a long range rig know how to analyze ballistics data and pick a load for your rifle that puts you in the kill zone for the longest period of time while not letting windage get out of hand. There is a balance and the least wind drift may or may not be the best answer. You may find a load that the wind drift difference is negligible when compared to how much longer you stay in the kill zone vertically as you drop through it.

 

[sp6x6]

How about the 250 NAB's, for my norma?

 

[Long Time Long Ranger]

They will kill an elk further than most could ever hit one. I shoot the 225 AB's in my lapuas and RUM's because at the distances I shoot these rifles mostly inside a half mile the BC difference of the 250's does not catch the 225's. The extra velocity of the 225's overcome the slight BC difference of the 250's within that distance. Either will kill an elk further than I can hit one. Doesn't mean it's right or wrong that is just what I do. If I go extreme range I get more bullet and a bigger gun.

 

[HARPERC]

This thread improves on a discussion our group has been having. LTLR says this very well, and I'm really glad he chose to back up (range wise) as I still consider 300 yards a long shot at big game, and my self imposed maximum is 600 yards. No disrespect intended for the folks who can, and do have different limits. At any rate thanks for taking the time to educate me.

 

[Topshot]

LTLR,

Have a look at the 225 grain Hornady Interbond projectile. It shoots much flatter than the 225 grain Accubond.

The published B.C. of the Interbond is way off. They just listed the Interbond as the same B.C. as the SST. I can tell you they are very different in real life.

 

[Long Time Long Ranger]

Thanks, I have shot the sst but not the interbond.

 

[Scot E]

LTLR,

Have a look at the 225 grain Hornady Interbond projectile. It shoots much flatter than the 225 grain Accubond.

The published B.C. of the Interbond is way off. They just listed the Interbond as the same B.C. as the SST. I can tell you they are very different in real life.

I have always wondered why the Interbond didn't have a higher BC than the SST's.

How did you find out that they just listed them the same?

What is the true BC number for the Interbond?

 

[Broz]

LTLR, I have a few questions for you if I may? Right now I am shooting my .338 (standard) Lapua Mag and loaded with the 300 gr Bergers with a MV of 2800 give or take a few fps. I feel it shoots very well and have taken game past 1100 yards on 2 occations with this rifle. This rifle is on a Mark V action and is over 18 lbs. I have past the 1000 round mark and even though it still will shoot 1/2 moa I know I will need to rebarrel one of these days. I have two primary rifles for hunting, a 300 win. and the Lapua. I use the 300 WM for lighter game to 1000 and I did take an elk with it last season at 803. The LM is my long range rifle for big game 1000 yards and beyond and have taken a bull at 1130 , one shot DRT. So, with all that said, do you feel I should look into rechambering to a .338 Lapua AI when the barrel time comes? I also plan to back down to a (28") sendero contour or slightly larger and replace the Mcmillan A-5 with something lighter to get its weight down to around 13lbs or so hopefully. I am a fan of H-1000, I will use 300 gr bullets and I am not sure I will gain enough MV to justify the change in dies, fireforming etc.

Thanks for your input.

Jeff

 

[Long Dog]

Just when I thought I was getting the hang of long range shooting, a post like this comes up and makes me wonder if I am shooting the right bullet at the right velocity. Thanks for the info and breaking it down into details LTLR, definately something else to add to my kitbag of knowledge.

 

[J E Custom]

They will kill an elk further than most could ever hit one. I shoot the 225 AB's in my lapuas and RUM's because at the distances I shoot these rifles mostly inside a half mile the BC difference of the 250's does not catch the 225's. The extra velocity of the 225's overcome the slight BC difference of the 250's within that distance. Either will kill an elk further than I can hit one. Doesn't mean it's right or wrong that is just what I do. If I go extreme range I get more bullet and a bigger gun.

Very good post LTLR !!!!

At one time I considered building myself an Excalibur because of the performance potential
but found that the RUMs and Lapua would meet or exceed my limit of 1100 yards (The older
I get the lower my limit).

As far as the bullets I came to the same conclusion about the 225 Accubonds over the 250s.
And settled on the 225s because of down range performance.

There are bullets with better BCs but I can depend on the Accubonds to perform at extended
ranges and they are very accurate.

Your post has good info and should help those that are thinking about a new build. (Why build
it if you don't need/use it).

Thanks again.

J E CUSTOM