Most stable bullet through Transonic in .308?

[VarmLR]

I'll shortly be using my heavy stalking rifle for long range target practice rather than competition. I've decided (sensibly) not to shorten the barrel's life unduly by switching to double base hot burning propellants or loading too hot, but am left with the conundrum of how to reach out with a 24 inch barrel.

 

My only choice, it would seem, is to search for a bullet that remains stable through the transonic range. Currently, I have stocks of #2155 to get through and whilst I can get them up to around 2700fps with N140, anything more on a cool day may need pretty compressed loads. The rifle handles up to 44.5gr N140 before pressure signs become an issue and I have had the odd stiff bolt lift during hotter weather with that load so backed off a bit.

 

Is there a better bullet that my 1/11 barrel can take full advantage of which remains stable? I know that I shouldn't be looking at 165/8gr bullets as many are 600 yd projectiles. How about 175gr to 190gr range? #7775 or#2220 spring to mind. In lighter bullets, they need to be jump tolerant which rules out the #2156 for me.

[GeorgeB]

The Sierra 190gr Match King is noted for its trans-sonic stability and should work well in a 1/11 barrel. However I am a bit concerned that you are getting pressure signs with 44.5 gr of N140 behind the 155gr SMK as that would be a mild load in my TR rifle, even though it has a "palma" tight bore barrel. What type of brass are you using?

[Swarovski1]

You don't say how far you intend to shoot.if 1000yds it will be fun.if you are going to try a double based powders N540 and AA2520 will give your bullets a boost.

[gbal]

Remington VSSF 308

 

Sierra 190HPBT Match King (Moly) 43.6 V140 for 2558 @ 65F,2531@ 31F

 

Lapua 185 Scenar Moly 43.4V140 for 2594 @42F

 

Allow for moly as well as working up ,as always.

 

Sierra about 1 moa at 1000 Diggle competition. .5 in rare benign conditions; 1.5 if normal wind errors.

 

gbal

[Laurie]

The 190gn SMK and 185gn Lapua D46 FMJBT are two oldie gut goodie designs for this purpose, both fully stabilised in an 11-inch twist. IMO the D46 is a much better choice than the well made but very high drag 185gn Scenar. There is also a fair bit of evidence that the rebated boat-tail shape is particularly well suited to trans and subsonic transitions.

 

The 'killer' design for this purpose though is the Berger 175gn OTM Match Tactical p/n 30105, designed specifically for military and civilian sniper / tactical comp use in shorter 11.25-inch twist barrels for 1,000 yards or more at modest MVs (ie 2,600-2,700 fps).

 

I've used this bullet and been impressed by it. There are however two significant downsides to it - finding any (real hen's teeth stuff in this country) and what you have to pay out if you're lucky enough to find any. Hannams mid year price list shows it at £54.50 / 100 - and that of course is before the PS dropped by 20-odd % against the USD.

[VarmLR]

Many thanks folks. Looks like the 190SMK is possibly my best option. I'll be shooting out to 1000 yds. (I'd be using #2155s if shooting to 800).

 

The Sierra 190gr Match King is noted for its trans-sonic stability and should work well in a 1/11 barrel. However I am a bit concerned that you are getting pressure signs with 44.5 gr of N140 behind the 155gr SMK as that would be a mild load in my TR rifle, even though it has a "palma" tight bore barrel. What type of brass are you using?

 

It only happened once George, on a particularly hot day. I'm using Lapua std large primer brass. Had flattened primers with the same load in PPU brass, again, on a hot day. Shot 44.2gr a few weeks back with zero pressure signs so can only put it down to temperature sensitivity. The rifle's a T3.

[TJC]

Finally some proof that the 168gr drops dead at 1.000 yards !

 

[Panda]

I'll second Laurie about the Berger 175gn OTM. I tried them at 1000yds in my Remy (26" barrel) using Viht N150. It was printing sub-moa groups from bullets set at 2.800" with a 0.256" jump at 2693fps.

[gbal]

Finally some proof that the 168gr drops dead at 1.000 yards !

https://youtu.be/H9n9r3Now7w

Wow....and it gets better ...the same LRS of Utah club has a 2240 yard hit with an unmodified K31 in 7.5 Swiss....wait for it.....with open sights.

 

So now we know what 1000y shooters are doing wrong....Progress does not March on...(ok .. there are a few flukey 2+ inch groups-but how many are on you tube...??)

 

Get up to speed on probability math-the best source is "Probability and Numbers for Newbies" in the two volume basic,and the three volume advanced sets.

 

The two volume set is currently on special offer at the higher three volume set price.

 

:-)

[rudie]

Tod Hodnett uses the 175 SMK and the 175 berger OTM at his long range traing classes

Very preditable trajectories is what he says.

 

I used the berger 175 OTM in a 308 (44grains of N140) V0= 830m/s) up to 1555meters not to many hits on a plate of 0.8 by 1.0meters but a few and the trajeactory predictions of the kestrel with AB where dead on, so the 175 OTM proved to me to give a stable transsonic and subsonic trajectory.

[GeorgeB]

If you do decide to try the 185 or 190gr bullets, I would strongly advise you to switch to N150, which was specifically designed for heavier bullets in .308.

 

Another propellant I would avoid with heavy bullets is RS52. I understand that this was used by some MR shooters recently (on the advice of an "expert") loaded behind 200gr Sierras and resulted in a spate of blown primers. A large qty of ammo had to be scrapped and replaced.

[Laurie]

Wow....and it gets better ...the same LRS of Utah club has a 2240 yard hit with an unmodified K31 in 7.5 Swiss....wait for it.....with open sights.

 

So now we know what 1000y shooters are doing wrong....Progress does not March on...(ok .. there are a few flukey 2+ inch groups-but how many are on you tube...??)

 

Get up to speed on probability math-the best source is "Probability and Numbers for Newbies" in the two volume basic,and the three volume advanced sets.

 

The two volume set is currently on special offer at the higher three volume set price.

 

:-)

 

 

Funny that isn't it? On You Tube, people make these wonder hits at 1,500 yards plus, but at Diggle I've seen other people likewise coached take 10 shots to find a 6x6ft target frame at a mere 1,000 yards with 308 Win in PSS, TRG etc type rifles, and if they're shooting the older 168s or some AMAX models frequently not finding it all!

 

One possible reason is that a You Tube mile may be somewhat shorter than 1,760 yards found in the more normal variant.

 

Another may be that the other 999 hopefuls trying the same trick and whose shots not only miss, but can't even be seen by the 'spotters' aren't very 'You Tubeable', so we don't get to see them.

 

Being a shade less cynical and a soupscon more charitable, just look at the 'range' the shot is being taken over. High desert? Kinda hot? Bisley in December this is not!This affects external ballistics markedly.

 

Take a typical handloaded TR / FTR / Palma loading from a 30-inch barrel rifle - the 155.5gn Berger Fullbore BT at 3,050 fps MV, an incomparably better loading in ballistics terms than that used in the video.

 

At Bisley on a cold winter's morning, it:

 

goes transonic at 1,100 yards

goes subsonic 1,200 yards

has a calculated terminal velocity of 845 fps at 1,800 yards

Needs 20.17-MOA windage in a 10 mph true crosswind

 

Get Scottie to beam the shooter and rifle to a high US desert, 90-deg F and 7,000 ft ASL and he gets:

 

goes transonic at 1,400 yards

goes subsonic 1,700 yards

has a calculated terminal velocity of 1,064 fps at 1,800 yards

Needs 12.34-MOA windage in a 10 mph true crosswind

 

That's quite a difference. When I shot at Raton, New Mexico in August 2013 my 1,000 yard elevation setting was IIRC around 7-MOA less than needed for Bisley, and 6-MOA less than my usual Diggle setting. (The Whittington Center ranges are ~7,500 ft ASL.)

 

Another interesting comparison from documented and reliable sources is two guys shooting at a gong in some American desert using the 308 AI improved version of the cartridge and the 220gn Sierra MK some years back and one of the many excellent features included in Precision Shooting magazine's sponsored book Precision Shooting at 1,000 yards, at around 1,400-1,500 yards if my memory is correct. This was a purpose built L-R rifle, used the higher performance Ackley Imp version of the cartridge, a much higher BC bullet and the report / photographs displayed some interesting features compared to the You Tube report. One was that to even see the gong / spot and correct strikes, the two worthies travelled out to the desert in the closing hour of the the night, set up in darkness and had around a half hour of shooting time after first light before wind and mirage made things impossible. Secondly, you have never seen scope mounts like this rifle had - custom built and many inches high with a ferocious downwards taper to get enough elevation adjustment for this sort of distance with 308 Win ballistics.

 

The 155.5/3,050 fps example again, needs 99.5-MOA elevation over a 100yd zero at our chilly Bisley 1-mile shoot; the baking hot high Nevada desert still needs a calculated 63-MOA rise. These sorts of elevations need some pretty specialised optics and mounts - like that's why so many of the mounts for real L-R rigs using the 400 Cheytac and 50 BMG have vast amounts of elevation adjustment built into the mounts as well as using 34 or 35mm body scopes allowing another vast amount of adjustment.

 

Now I know scopes have moved on a long way in the last 10 years and there are a few examples around with 100-MOA of internal adjustment, but even so, the You Tube subject here looks so common or garden a set-up, you've got to wonder just what the aiming mark was and where it was in relation to the milk jug.

[VarmLR]

 

 

Funny that isn't it? On You Tube, people make these wonder hits at 1,500 yards plus, but at Diggle I've seen other people likewise coached take 10 shots to find a 6x6ft target frame at a mere 1,000 yards with 308 Win in PSS, TRG etc type rifles, and if they're shooting the older 168s or some AMAX models frequently not finding it all!

 

One possible reason is that a You Tube mile may be somewhat shorter than 1,760 yards found in the more normal variant.

 

Another may be that the other 999 hopefuls trying the same trick and whose shots not only miss, but can't even be seen by the 'spotters' aren't very 'You Tubeable', so we don't get to see them.

 

Being a shade less cynical and a soupscon more charitable, just look at the 'range' the shot is being taken over. High desert? Kinda hot? Bisley in December this is not!This affects external ballistics markedly.

 

Take a typical handloaded TR / FTR / Palma loading from a 30-inch barrel rifle - the 155.5gn Berger Fullbore BT at 3,050 fps MV, an incomparably better loading in ballistics terms than that used in the video.

 

At Bisley on a cold winter's morning, it:

 

goes transonic at 1,100 yards

goes subsonic 1,200 yards

has a calculated terminal velocity of 845 fps at 1,800 yards

Needs 20.17-MOA windage in a 10 mph true crosswind

 

Get Scottie to beam the shooter and rifle to a high US desert, 90-deg F and 7,000 ft ASL and he gets:

 

goes transonic at 1,400 yards

goes subsonic 1,700 yards

has a calculated terminal velocity of 1,064 fps at 1,800 yards

Needs 12.34-MOA windage in a 10 mph true crosswind

 

That's quite a difference. When I shot at Raton, New Mexico in August 2013 my 1,000 yard elevation setting was IIRC around 7-MOA less than needed for Bisley, and 6-MOA less than my usual Diggle setting. (The Whittington Center ranges are ~7,500 ft ASL.)

 

Another interesting comparison from documented and reliable sources is two guys shooting at a gong in some American desert using the 308 AI improved version of the cartridge and the 220gn Sierra MK some years back and one of the many excellent features included in Precision Shooting magazine's sponsored book Precision Shooting at 1,000 yards, at around 1,400-1,500 yards if my memory is correct. This was a purpose built L-R rifle, used the higher performance Ackley Imp version of the cartridge, a much higher BC bullet and the report / photographs displayed some interesting features compared to the You Tube report. One was that to even see the gong / spot and correct strikes, the two worthies travelled out to the desert in the closing hour of the the night, set up in darkness and had around a half hour of shooting time after first light before wind and mirage made things impossible. Secondly, you have never seen scope mounts like this rifle had - custom built and many inches high with a ferocious downwards taper to get enough elevation adjustment for this sort of distance with 308 Win ballistics.

 

The 155.5/3,050 fps example again, needs 99.5-MOA elevation over a 100yd zero at our chilly Bisley 1-mile shoot; the baking hot high Nevada desert still needs a calculated 63-MOA rise. These sorts of elevations need some pretty specialised optics and mounts - like that's why so many of the mounts for real L-R rigs using the 400 Cheytac and 50 BMG have vast amounts of elevation adjustment built into the mounts as well as using 34 or 35mm body scopes allowing another vast amount of adjustment.

 

Now I know scopes have moved on a long way in the last 10 years and there are a few examples around with 100-MOA of internal adjustment, but even so, the You Tube subject here looks so common or garden a set-up, you've got to wonder just what the aiming mark was and where it was in relation to the milk jug.

 

 

My thoughts exactly Laurie.

 

To be fair, that chap's scope has around a whopping 150 moa of internal adjustment (it's an SWFA 12 x 40mm, 30mm tube), so should have the reach at a mile to get out there with an aim point on the target with 63moa over 100yd zero. assuming of course a relatively centred ret for the zero. It's a shame we don't have access to similarly (sensibly priced) decent optics here, but with our duller skies, we need all the help we can get with good European (in my case, Japanese) glass!

 

Mine will get me to 1000 easily, but I'd need somewhere slightly warmer than the Nevada desert for a mile!

[VarmLR]

 

 

Funny that isn't it? On You Tube, people make these wonder hits at 1,500 yards plus, but at Diggle I've seen other people likewise coached take 10 shots to find a 6x6ft target frame at a mere 1,000 yards with 308 Win in PSS, TRG etc type rifles, and if they're shooting the older 168s or some AMAX models frequently not finding it all!

 

One possible reason is that a You Tube mile may be somewhat shorter than 1,760 yards found in the more normal variant.

 

Another may be that the other 999 hopefuls trying the same trick and whose shots not only miss, but can't even be seen by the 'spotters' aren't very 'You Tubeable', so we don't get to see them.

 

Being a shade less cynical and a soupscon more charitable, just look at the 'range' the shot is being taken over. High desert? Kinda hot? Bisley in December this is not!This affects external ballistics markedly.

 

Take a typical handloaded TR / FTR / Palma loading from a 30-inch barrel rifle - the 155.5gn Berger Fullbore BT at 3,050 fps MV, an incomparably better loading in ballistics terms than that used in the video.

 

At Bisley on a cold winter's morning, it:

 

goes transonic at 1,100 yards

goes subsonic 1,200 yards

has a calculated terminal velocity of 845 fps at 1,800 yards

Needs 20.17-MOA windage in a 10 mph true crosswind

 

Get Scottie to beam the shooter and rifle to a high US desert, 90-deg F and 7,000 ft ASL and he gets:

 

goes transonic at 1,400 yards

goes subsonic 1,700 yards

has a calculated terminal velocity of 1,064 fps at 1,800 yards

Needs 12.34-MOA windage in a 10 mph true crosswind

 

That's quite a difference. When I shot at Raton, New Mexico in August 2013 my 1,000 yard elevation setting was IIRC around 7-MOA less than needed for Bisley, and 6-MOA less than my usual Diggle setting. (The Whittington Center ranges are ~7,500 ft ASL.)

 

Another interesting comparison from documented and reliable sources is two guys shooting at a gong in some American desert using the 308 AI improved version of the cartridge and the 220gn Sierra MK some years back and one of the many excellent features included in Precision Shooting magazine's sponsored book Precision Shooting at 1,000 yards, at around 1,400-1,500 yards if my memory is correct. This was a purpose built L-R rifle, used the higher performance Ackley Imp version of the cartridge, a much higher BC bullet and the report / photographs displayed some interesting features compared to the You Tube report. One was that to even see the gong / spot and correct strikes, the two worthies travelled out to the desert in the closing hour of the the night, set up in darkness and had around a half hour of shooting time after first light before wind and mirage made things impossible. Secondly, you have never seen scope mounts like this rifle had - custom built and many inches high with a ferocious downwards taper to get enough elevation adjustment for this sort of distance with 308 Win ballistics.

 

The 155.5/3,050 fps example again, needs 99.5-MOA elevation over a 100yd zero at our chilly Bisley 1-mile shoot; the baking hot high Nevada desert still needs a calculated 63-MOA rise. These sorts of elevations need some pretty specialised optics and mounts - like that's why so many of the mounts for real L-R rigs using the 400 Cheytac and 50 BMG have vast amounts of elevation adjustment built into the mounts as well as using 34 or 35mm body scopes allowing another vast amount of adjustment.

 

Now I know scopes have moved on a long way in the last 10 years and there are a few examples around with 100-MOA of internal adjustment, but even so, the You Tube subject here looks so common or garden a set-up, you've got to wonder just what the aiming mark was and where it was in relation to the milk jug.

 

 

My thoughts exactly Laurie.

 

To be fair, that chap's scope has around a whopping 150 moa of internal adjustment (it's an SWFA 12 x 40mm, 30mm tube), so should have the reach at a mile to get out there with an aim point on the target with 63moa over 100yd zero. assuming of course a relatively centred ret for the zero. It's a shame we don't have access to similarly (sensibly priced) decent optics here, but with our duller skies, we need all the help we can get with good European (in my case, Japanese) glass! Mine will get me to 1000 easily, but I'd need somewhere slightly warmer than the Nevada desert for a mile!

 

If you do decide to try the 185 or 190gr bullets, I would strongly advise you to switch to N150, which was specifically designed for heavier bullets in .308.

 

Another propellant I would avoid with heavy bullets is RS52. I understand that this was used by some MR shooters recently (on the advice of an "expert") loaded behind 200gr Sierras and resulted in a spate of blown primers. A large qty of ammo had to be scrapped and replaced.

 

 

I'll be sticking with N140 George, as I use it for many other loads. I'm surprised that no-one yet has mentioned the 155 TMK , or its 168/175 stablemates. Their BCs are way higher than some of the heavier pills, so velocities for the lighter TMKs ought, in theory, to give them a distinct LR advantage. Anyone tried the 155? (BC 0.519). The 175TMK has a BC of 0.545. Not sure of how stable these are through transonic though. Brian Litz has now tested those bullets and the G7 data looks encouraging:

 

http://bulletin.accurateshooter.com/2015/05/litz-field-tests-bcs-of-sierra-tipped-matchkings/

 

so, the 175 TMK, with a full charge of n140 for around 2550 fps ought to stay supersonic judging by the tested G7.

[GeorgeB]

They certainly look promising. If you do try them, let us know how you get on.

[gbal]

Good points Laurie,as ever.

 

Often enough too,these long range wonder shots are acieved within a rather few 'sighters' on the day.

 

What isn't typically included in the edited you tube video,is that there was some acclimatising to the heat done on the previous day,and a few boxes of ammo used up in getting the rig more or less sighted in (more or less,because it depends on time of day-or rather temperature etc,as you shown with your data,as ever.)

So,it's more one hit with seven shots,after several boxes of ammo the day before,and we won't try for a repeat hit,since misses (even in 7 shots) will show that statistically (ie in the real world,rather than our dream world) we are pi**ing about in the wind.

 

Probability is a near certainty in LR shooting,so-

 

 

" Ask not what your hit can do for you,ask rather what you can do for all your non hits"

 

gbal

 

 

 

g

[Swarovski1]

A milk jug at 1 mile with a 308.jeez that's along way.ive always to told a 308 is past its accuracy limit at 900 yds. Who do make all this up.i blame laurie and gbal

[gbal]

" To miss once might be bad luck,but to miss twice,suggests bad ballistics".

 

Oskar Wylde,"The Importance of Being Accurate."

 

gbal

[DW58]

" To miss once might be bad luck,but to miss twice,suggests bad ballistics".

Oskar Wylde,"The Importance of Being Accurate."

g

Made I laugh ... ... ...

[Laurie]

A milk jug at 1 mile with a 308.jeez that's along way.ive always to told a 308 is past its accuracy limit at 900 yds.

 

 

Don't tell that to the Match Rifle people who shoot at up to 1,225 yards here and further in some other Commonwealth countries. There was a ballistics discussion in another forum a few years back after the GB MR team went on an Australian tour that included 1,500 yard matches on some range in New South Wales. (Tried to find the thread, but failed.) This was another hot, up in the sky venue and 210gn Berger and Sierra VLDs remained supersonic at the target in the thin air. However, MR is a pretty specialised form of 308 Win prone shooting and its relatively small following keep their loading secrets and resulting astronomic MVs very much to themselves. Incidentally, the old 190gn SMK was a mainstay of MR shooting until the modern breed of heavy VLDs and Hybrids appeared. It was liked because bullets were subsonic at Bisley at 1,200 in those days and this bullet along with its 200gn stablemate were amongst the few designs that retained stability in all conditions.

[VarmLR]

Out of interest Laurie, have you had a chance to play around with the 168 TMK yet? I'm guessing that this is an all new design rather than just an SMK with a tip (as the BC suggests it's new....it's too much over the standard one to be pushed up that far with just a tip), which raises the all important "is this a 600 yd bullet or a 1000 yd bullet? The only thing I can glean from a visual comparison is that it does seem to have a more pronounced boat tail to the standard SMK, almost as long as the 175 HPBT in fact.

[Swarovski1]

" To miss once might be bad luck,but to miss twice,suggests bad ballistics".

Oskar Wylde,"The Importance of Being Accurate."

gbal

I would like to see a 338 lap mag or cheytac type calibre hit the milk jug first time at 1 mile.

[VarmLR]

I would like to see a 338 lap mag or cheytac type calibre hit the milk jug first time at 1 mile.

 

Nearest I've ever seen to this was "Tiborasaurus Rex" (Sniper 101 on You-Tube) hitting a beer can first shot at 1236 yards and that was both exceptional shooting and exceptional good luck! That was with a .338 Lap mag shot in the Rockies. Most of you have probably already seen this, but just in case you haven't, here it is:

 

https://www.youtube.com/watch?v=emJ0RToUYGE

[Swarovski1]

Yeah seen it yonks ago.how do we know it was his first shot.that shot was way short of 1760yds.once you see fall of shot you can walk it on the target but not really so much skill in that.just need a good spotter.

[TJC]

Nearest I've ever seen to this was "Tiborasaurus Rex" (Sniper 101 on You-Tube) hitting a beer can first shot at 1236 yards and that was both exceptional shooting and exceptional good luck! That was with a .338 Lap mag shot in the Rockies. Most of you have probably already seen this, but just in case you haven't, here it is:

 

https://www.youtube.com/watch?v=emJ0RToUYGE

 

 

I love all the critics on here citing warm up shots, walking it in with good spotters and citing altitude, internal adjustment limitations etc....you aren't keeping up with the times. The truth is these guys have strict rules and if you want to get out from your mum's basement you can go out there and try it for yourself. Only 12 people have so far achieved the 1-mile challenge at LRSU (yes it's called Long Range Shooters Utah for a reason). These guys are pushing the boundaries, they should be applauded. We don't have many places in this country to shoot out to a mile and that's probably the single biggest constraint we have - that and internet commandos saying it can't be done. I'm in the US next month shooting with some of these guys. They are good shooters who are prepared to try and usually fail but when they achieve something don't criticise them unless you've tried it yourself. If you haven't and are looking for excuses keep citing ballistics and warm-up shots. You are getting left behind - long range shooting has progressed more in the last decade than it has in the last half century.

 

Oh and watching this 11-yr old do it on the first shot will really annoy the cynics !

 

https://youtu.be/E7XeucaeaR0