For the 308 or any other caliber, each increase in muzzle velocity of 100 fps is only going to give about a 50 yard increase in range.
For BC if you increase it by 10% then you get a 10% increase in range. For a given cartridge both muzzle velocity and BC have practical limits on the amount you can increase them. One should keep in mind that BC is tied to sectional density and muzzle velocity is tied to weight.

What Litz has done is change the shape factor without sacrificing either BC nor sectional density and gained large increases in yardage out to whatever range the shooter and spotter have the skill to achieve with the equipment they have available.

I ordered a box of the bullets for my 308. Here are a couple of pictures of the box and then there is a picture of two Sierra 175 MK on the left and two Berger 175OTMs on the right. It was misting rain at the time of the picture.

Deer season starts Saturday after Thanksgiving so I needed to go to the rifle range to check some zeros and took along some loads for the OTMs to test for accuracy. I normally shoot 43.4 grains of Varget in RWS cases for competition with the Sierra 175 MK and on calm days that will group about 0.3-0.4 for three shots. For this test I am using Winchester cases that have about 1 grain more volume than RWS but are less consistent in quality. It was gusting wind up to 5mph today so groups were a little more open.

First picture is of the standard 175MK loads where I am adjusting the zero between the top 3 shot group and the bottom 3 shot group. Aim point is the upper right corner of the tape.

Second picture is the Berger 175 OTMs with three different charges of Varget and 5 shot groups instead of 3 shot groups. All three groups go just under 0.5 for five shots. This is acceptable accuracy for me and this particular rifle.

I think I will try them out on deer this season and see how they work.
It will probably be a long time before I get to test past transonic ranges so don't be holding your breath waiting on it. :D

The second edition of Litz' book is very good and fairly easy to understand. There are a few errors but he gives a good explanation of the difference between secant and tangent ogive bullets and the ballistic differences between shorter and longer boat-tailed projos.

I am guessing but Litz and Berger have done extensive recent original art designing "Hybrid" bullet profiles, melding what they consider the best of both tangent and secant ogives. I assume that's what they've done with the 175.

My experience with 300-grain .338 Lapua Magnum projos has Sierra Match Kings running out of steam around 1600 Meters (they definitely do NOT fly true transitioning thru trans-sonic); Bergers around 1800; and Lapua Scenars right about 2 klicks (all using the same primer, brass, and powder charges).

RUAG (Switzerland) has a new proprietary 300-grainer they are adding to their Swiss-P line that is aimed at meeting USSOCOM's 1500-meter PSR spec as well.

OK - Slightly off topic but you've got my undivided attention. Have you had an opportunity to look at the Hornady 285gr .338 Bullet yet?

PS - You coming to Bragg next month for the sniper competition?

I've looked at the Hornady 285s but not shot a bunch (maybe 20 rounds). I have a photo somewhere with sectioned Hornady 285, Scenar, and Match King or Berger side-by-side. The Hornadys are interesting in that the nose of the projo is hollow (like a 308 155-grain Scenar) while the jacket is nearly the same length as the 300-gr Scenar, pushing the center-of-gravity towards the rear.

We're getting to Fayetteville on Wednesday night (the 7th).

Brush- I have a Rem 700Mlr in .338 Lapua. It is just a factory rifle with a stock muzzle brake. It has much less recoil than my son's M70 .300 Winmag. It is not as bad as people make it out to be. I have only had it for about 8 months. I use the 300gr SMK with good results. Now I have to buy a better rangefinder, though....

I should add that I am a rookie at this and no where near the class of the other QP's commenting on this thread. My comment was on the recoil remark only...

As I mentioned in post #34 I would try to test the transonic stability of the bullet. This has finally happened and as luck would have it the test weather conditions were pretty raggedy but I shot anyway.

Because I do not have access to a 1500 yard range I decided to develop a reduced velocity load that would go subsonic at about 700-750 yards. One of my loading manuals had a starting load for 175 grain bullets and Varget so I put together a load with a muzzle velocity of 2250 fps. This load was tested for accuracy at 100 yards by firing two groups from the bench. Groups size CTC was less than 0.4.

Ttransonic stability was tested during a F-class match at R4 Quantico USMC. There was the worst headwind I have experienced in the last six or seven years. It was about 20 mph and varying from 10:00 to 2:00. During the unlimited sighter stage at 800 yards the rifle was zeroed for the 155.5 Berger (MV= 2800fps) that I normally compete with and also the 175 OTM (MV-2250fps). The 800 yard stage was fired with the 155.5 Berger and produced an average per shot score of 9.3 which was probably the best score I have ever gotten at that stage. The “open” rifles were averaging about 9.0. But what I got was a period of wind that stayed at 11:00 so I didn’t have the direction switches that are so damaging to the score. So the test was off to a bad start being as I had shot about 5 points better than normal under some of the worst conditions.

At 900 yards I used the 175 OTMs and got a per shot average of 7.3 being as the wind was back to switching direction. At 1000 yards I went back to the Berger 155.5 and got a per shot average of 6.75. Those of us shooting “FTR” (308) were recording misses off of both sides of the target because the wind was so unpredictable. The interesting thing is that the subsonic, slow moving 175 OTM produced a higher per shot score than the faster supersonic 155.5 Berger at the 100 yards difference --- 7.3 vs 6.75. This is about a half MOA difference.

So I conclude that the 175 Berger even when it is well below the transonic zone still retains very good accuracy.

For those who forgot, I tested terminal performance of the 175 OTM at normal velocity on a deer in this thread.


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