New Transonically Stable 308 Bullet

[Buffalobob]

Gene

I would ask you two questions just so we start at the same point of departure.

1. Do you believe the 175 SMK is stable through the transonic zone as it is my understanding that it is not; although, I have never personally verified it?

2. Do You believe the old M118 SB (173 gr FMJBT) was stable through the transition zone; as it is my understanding that it was, and that was my observation of it?


The official Americal record in RVN with the 308 is 1600 meters (not yards) and the unofficial is further.

[mojaveman]

Originally Posted by Buffalobob

The official Americal record in RVN with the 308 is 1600 meters (not yards) and the unofficial is further.

Remarkable.

With an M-21 or something else?

[Buffalobob]

Attached is an Adobe file about the Chu Lai Sniper School and, other than a few CIA test rifles, the snipers routinely used the M21 and Lake City M118 SB.

Lones Wigger is easy to find on the internet and we exchanged emails once about RVN records.

http://www.sports-reference.com/olym...-wigger-1.html

http://www.facebook.com/people/Lones-Wigger/1537531224

Virgil Umphenour runs a guide service with his son and daughter in Alaska

http://www.huntalaskawithus.com/about_huntalaska.htm

One day in RVN, Virgil sent word that he was going to court martial a "raggedy ass, wet behind the ears lieutenant" if I did quit being an asshole. I had tactical control of the snipers in the field but he had administrative control.


I would just say that my experience was about as the adobe file says. Lots of 100 - 500 yards kills and wounded and only very, very seldom are you in a situation to get a really good extreme range shot.

I believe the Iraq record with the 308 was set at 1250 meters with a M24 bolt gun using the M118LR (not M118 SB) with the 175 SMK and is borderline super sonic range but I don't know the atmospheric conditions so I would not make any definitive statement about it other than a good shot is a good shot.

[Gene Econ]

Originally Posted by Buffalobob

Gene

I would ask you two questions just so we start at the same point of departure.

1. Do you believe the 175 SMK is stable through the transonic zone as it is my understanding that it is not; although, I have never personally verified it?

2. Do You believe the old M118 SB (173 gr FMJBT) was stable through the transition zone; as it is my understanding that it was, and that was my observation of it?


The official Americal record in RVN with the 308 is 1600 meters (not yards) and the unofficial is further.

Bob:

I don't think anything is stable through the transonic zone. Not being a wise guy about it. The differences are probably in the degree of instability. I also figure twist rate and velocity would play a role as that determines nutation or precession -- both of which probably have something to do with stability when transitioning.

I can comment on my observations of consistency at 1K though.

I would give the 118LR an edge over the 118 SB at 1K in terms of consistency given shooters who are relatively new to distance shooting. The difference is evident but in my opinion both are more than adequate for combat demands. However, neither are competitive in today's precision shooting sports.

I can say with certainty that 118LR and 118 SB held considerably better at 1K than the old 852 Match. However, that old 168 grain bullet from the 852 had transitioned completely to subsonic under most environmental conditions. Also, the bullet design of that one simply wasn't focused towards performance much beyond 300.

I kind of look at it like this. Maybe one percent of the competitive side of long range shooting will be good enough at those distances where results can be conclusively shown to be due solely to instability caused by transonic passage. So, the 'so what' factor plays a role at least in my terms.

As for a 1600 meter shot with a M-21 and the old 118 Match you guys used in Vietnam. With an ART scope? You are looking at about ten minutes per hundred after 1K meters with that cartridge out of a 21 so somehow the guy held about sixty minutes over? Man, I can't see how the shooter could even see another human with an ART scope at that distance unless they were in a high desert right at sunrise with absolutely no wind or mirage. Not to mention someone being able to spot the shot.

I do defer to Rick or Sinister on the transonic issue and the 118's though. To me, the discussion is a technical one that can't be predicted and certainly can't be changed by the shooter. So, it just doesn't hit the level of importance for my purposes and in my conditions.

Gene

[Buffalobob]

I count it as a good day when I actually learn something new about long range shooting. And your comment is really intriguing to me so I am going to keep it in mind as it would seem to be a good assessment.

I don't think anything is stable through the transonic zone. Not being a wise guy about it. The differences are probably in the degree of instability. I also figure twist rate and velocity would play a role as that determines nutation or precession -- both of which probably have something to do with stability when transitioning.

So, I am about to the end of my knowledge base on the subject and only have a few thoughts and observations left.

You mention optics used back then and that certainly is important. In about 1977 I began noticing that the animals I hunted were often over othe next ridgeline so I bought a 3X9 Redfield Accutrac. That thing was so great under 500 yards that I built up a whole rifle and topped it off with a 6X18 Redfield accuRange. In its day and in my early years it was great glass. I sold the 6X18 about three years ago because it was trash compared to the new Luepolds and Nightforces. Whether is was the coatings and glue deteriorating or my eyes deteriorating or both I do not know. I also had a friend who built a USMC M24 clone and topped it with a RVN correct Redfield and I looked through it at 300 yards and it was trash although I never adjusted the eyepiece so that judgement is flawed. I have a Wilde Rangefinder (WWII vintage) and I can see clearly to 3K with it. So I am not at all certain about the optics of the RVN era versus what I use today.

However you make this comment

can't see how the shooter could even see another human with an ART scope at that distance unless they were in a high desert right at sunrise with absolutely no wind or mirage. Not to mention someone being able to spot the shot.

As I mentioned earlier, there is the 1600 M official Americal record and then there is the "unofficial" record. After the Americal left RVN, the 196th LIB operated as an independent unit. The whole long story of how that record was broken is hilarious but I will save it for another day.
I will preface my remarks that everything hinges upon my memory which is about as reliable as my other body parts.

The firing position was the top of a perimeter bunker at Bn Firebase on a ridge and downhill to the old French RR. The background was a water filled rice paddy. Target was two NVA solder walking ( Can you believe shooting a guy walking at over a mile with a 308?) along the RR. Shooter was a second tour sniper using a M21, ART and M118SB with his regular partner spotting on the Bn arty spotting scope. Spotter was calling adjustment based upon splashes in the rice paddy and the NVA reactions. Fourth and fifth round hits on the same guy. One more for the Body Count Board!

Unusual and unique circumstance under which the shots were made and for certain no other sniper I ever had was good enough to do it.

So before I conclude, I will say that my son and my daughter and myself have won mantel trinkets shooting the 175 Sierra MatchKing in long range F-class and several animals have been killed with it which have been posted on this forum. Its a great bullet and I have some loaded right now just for hunting. I also shoot Bergers and have killed several animals beyond 1K with them so they are also good bullets.


Conclusion

Given the great improvements in metallurgy and barrel making and the great improvement in optics, rangefinding, atmospheric meters and handheld ballistic computers and given the continued widespread use of the 308 as a sniper cartridge is seems that one would stop and think whether the bullet in use is limiting the effective range of the snipers because it will not transition well. Back in the good ole days Sniper School was three weeks. Nowadays it is much longer and much improved (I would hope) and the snipers should be capable of outperforming those of my generation. Why aren't the RVN records being broken? Is it because of bullet design?

[Gene Econ]

Originally Posted by Buffalobob

So, I am about to the end of my knowledge base on the subject and only have a few thoughts and observations left.

You mention optics used back then and that certainly is important. In about 1977 I began noticing that the animals I hunted were often over othe next ridgeline so I bought a 3X9 Redfield Accutrac. That thing was so great under 500 yards that I built up a whole rifle and topped it off with a 6X18 Redfield accuRange. In its day and in my early years it was great glass. I sold the 6X18 about three years ago because it was trash compared to the new Luepolds and Nightforces. Whether is was the coatings and glue deteriorating or my eyes deteriorating or both I do not know. I also had a friend who built a USMC M24 clone and topped it with a RVN correct Redfield and I looked through it at 300 yards and it was trash although I never adjusted the eyepiece so that judgement is flawed. I have a Wilde Rangefinder (WWII vintage) and I can see clearly to 3K with it. So I am not at all certain about the optics of the RVN era versus what I use today.

However you make this comment


As I mentioned earlier, there is the 1600 M official Americal record and then there is the "unofficial" record. After the Americal left RVN, the 196th LIB operated as an independent unit. The whole long story of how that record was broken is hilarious but I will save it for another day.
I will preface my remarks that everything hinges upon my memory which is about as reliable as my other body parts.

The firing position was the top of a perimeter bunker at Bn Firebase on a ridge and downhill to the old French RR. The background was a water filled rice paddy. Target was two NVA solder walking ( Can you believe shooting a guy walking at over a mile with a 308?) along the RR. Shooter was a second tour sniper using a M21, ART and M118SB with his regular partner spotting on the Bn arty spotting scope. Spotter was calling adjustment based upon splashes in the rice paddy and the NVA reactions. Fourth and fifth round hits on the same guy. One more for the Body Count Board!

Unusual and unique circumstance under which the shots were made and for certain no other sniper I ever had was good enough to do it.

So before I conclude, I will say that my son and my daughter and myself have won mantel trinkets shooting the 175 Sierra MatchKing in long range F-class and several animals have been killed with it which have been posted on this forum. Its a great bullet and I have some loaded right now just for hunting. I also shoot Bergers and have killed several animals beyond 1K with them so they are also good bullets.


Conclusion

Given the great improvements in metallurgy and barrel making and the great improvement in optics, rangefinding, atmospheric meters and handheld ballistic computers and given the continued widespread use of the 308 as a sniper cartridge is seems that one would stop and think whether the bullet in use is limiting the effective range of the snipers because it will not transition well. Back in the good ole days Sniper School was three weeks. Nowadays it is much longer and much improved (I would hope) and the snipers should be capable of outperforming those of my generation. Why aren't the RVN records being broken? Is it because of bullet design?

Bob:

Don't want to make a mess of this one so will be careful about what I say.

I have shot the 24 with the issued M-3 optic at about 1250 - 1300 meters and had to put on all elevation and hold at the base of the duplex. That got the 118 SB out to about 1300. If I had to push it another hundred meters, it would have been impossible for me to see the target through the optic. It brings up something. How could the shooter have seen the targets with that ART scope at that distance? From what I can recall about the ART Scopes, you maxed them out at 1K and I can't see how someone could see a target through their scope at 1600 meters using the type of hold over needed. Just food for thought.

As for guys doing or not doing what this one team did in Vietnam I can only offer some potential reasons. First is that the guys today must ID the target as a threat. Since the enemy doesn't wear a uniform, this means they must see a weapon. Hard to do at those distances with a 10X optic. Also, the conditions you mentioned are very unique. Team on a hill, enemy crossing a rice paddy. Ability to see the bullets literally splash in the water which is way more precise than seeing dust kick up. And in a ten year long war it happened only once.

Technology has gotten better but not significantly better unless you get into night vision and thermals. The old 173 grain service bullet was designed in the 1930's and improvements in design have happened but not enough to make a significant difference in danger space -- which equates to hit probabilities. Basically, the 118 SB and LR are 600 meter shooters and I would bet that if accurate records were kept you would find the majority of one or two shot engagements with 118 SB or LR resulting in a hit happened under 600 meters with the majority at 500 or less.

Another thing to consider and also is probably a reason why no one cares about record keeping is this. When does a shot stop being due to skill and more due to luck? Three shots -- four -- five? That is the big problem if the goal is to see who got the longest shot with a 7.62 rifle.

About the only thing I can say with certainty is that the guys will take the shot if they are allowed to under what ever ROE they must follow and if it means a shot past a reasonable distance, they will certainly try. I can not speak for SF here so understand I am talking about the Infantry. Maybe some SF guys have done the same? I would not know but I do know that some Infantrymen have been successful at distances past 1K but it certainly isn't the rule.

Gene

[Peregrino]

SF shooters have also been successful beyond 1000M in the current conflicts, sometimes with .308s, more often with .300s and .338s. I think there's even a couple of .50s out there. I'm not aware of any one-shot kills beyond about 1200m by anybody with any weapon/ammo combo. Even the "records" touted here in other threads. All (that I'm aware of) have required adjusting fire and using compensated aimpoints (and targets that accept "enshalah" as a fact of life). It doesn't count as "sniping" when it amounts to the same thing as hitting a target in a MG's beaten zone.

I like the M21 as well as anyone - it's the first DM rifle SF taught me to shoot. It's a sweet 600m rifle despite the POS ART II scope (OK - so I'm nostalgic about wood stocks). Hitting targets with one at 1200m+ (especially with M118SB) is luck and claiming otherwise is the same as claiming a shit shot in a pool tournament.

[Gene Econ]

Originally Posted by Brush Okie

I have heard the new 155 palma Sierra match king is an exellant 1000 yard bullet. Its BC is

.504 @ 2700 fps and above
.470 between 1800 and 2700 fps
.430 between 1500 and 1800 fps
.380 @ 1500 fps and below

The 175 gr is as follows

.505 @ 2800 fps and above
.496 between 2800 and 1800 fps
.485 @ 1800 fps and below

Soo in theory the 155 should be better at long range in the 308 since getting 2800 fps out of the 308 with a 175 is pushing the pressure limits while 2700 fps or a little better is a little more doable.

For the 30-06 or 300 WM I am thinking the 190

.533 @ 2100 fps and above
.525 between 2100 and 1600 fps
.515 @ 1600 fps and below

or the 220 gr sierra match kings would be a better choice

.629 @ 2100 fps and above
.624 between 2100 and 1700 fps
.608 @ 1700 fps and below

http://www.sierrabullets.com/index.c...c&bullettype=0

Anyone have any thoughts?

Now I realize all things being equal heavier bullets retain velocity better but the differance in BC etc I am thinking the 155 MIGHT be a better choice for long range in the 308.

BO:

Any of the match grade 155's are excellent bullets. Note they were designed very specifically for Palma shooting. Generally they use a 1 turn in 13 inch twist, 30 inch long barrel in order to stabilize that specific bullet and to get the 2950 plus FPS needed to ensure it is above the speed of sound at 1K. International Plama rules demand a bullet of 155 grains or lighter and 7.62 / .308 cartridge. US Palma lets you shoot any bullet weight but it must be .30 caliber and I believe is restricted to the .308 cartrdge. Understand that Palma rifles are also restricted in weight.

So, in a way you see why those bullets were designed the way they are. To feed a very specific need of a very specific sport. Would they be fine for military purposes? I don't think so because you don't see 30 inch long barrels on M-24's and you need that speed for that shorter and lighter bullet to stay above the speed of sound.

Personally and for military applications I see .30 caliber bullets weighing in the 170 - 180 grain range is about ideal to maximize danger space given 20 inch + - barrel lengths, a requirement to keep the bullet length down to maximize available cartridge capacityand magazine seating, while allowing for a fast enough velocity for performance to practical combat ranges -- which I see as 600 meters or less but the Army sees as 800 meters or less.

Another thing you need to consider is recoil effects. The higher the recoil, the more negatively it affects the shooter. A 155 Palma load is very hot -- too hot to blast regularly from standard receivers but its recoil is still noticeably less than a round of 118 shot from a 24 or 110. That means a-lot when talking about blasting those antique 190's and 220's.

Oh yes, note I did not get into BC comparisons. Although they are of value in decisions on ammunition that shooters make, you will never see them become the primary factor. Accuracy, velocity, and terminal effects are generally the primary issues going into a decision on some sort of cartridge and bullet. Those three get mixed up in priority based on the specific need but those are generally the three issues involved with decisions. BC's get involved after initial decisions are made and a guy has narrowed down his potential choices. Even then, they may not mean anything.

As a general rule, from the barrel to 300 the BC has very little meaning. From 300 - 500 it has some meaning and from 600 out it does have meaning you can actually see in reality. But only when you are looking at equal velocities and BC differences of at least 5 %.

Gene

[Buffalobob]

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.

[Buffalobob]

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.

[Buffalobob]

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.

[Sinister]

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.

[Peregrino]

Originally Posted by Sinister

----- 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?

[Sinister]

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).

[mark46th]

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...