168 Amax transonic performance???

[flyboy]

I will have a opportunity to shoot past 1000 yards, possible to 1200+ in a few weeds and was wondering if the 168 Amax suffered from the same transonic destabilization problems as the 168 SMK's. The thing is I have a bunch of 168 Amax's and only a hand full of the 175's so if I can get away with using them for this outing, that would be great. If they work, I have a great load other wise Time to go buy more 175 MK's

Thanks

 

[flyboy]

Re: 168 Amax transonic performance???

Really? No one has anything to say about this?

 

[pwc001]

Re: 168 Amax transonic performance???

168 Amaxs shot very well in my rifle and shot decent groups out to 1000, that was as far as I shot them. it was just a factory sps-v. I still shoot the 168's out of that rifle. I think this has been asked before, you can try searching.

 

[flyboy]

Re: 168 Amax transonic performance???

You've been hear long enough to know what I would end up with on that search. I tryied and after four pages gave up.

 

[RADcustom]

Re: 168 Amax transonic performance???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: flyboy</div><div class="ubbcode-body">I will have a opportunity to shoot past 1000 yards, possible to 1200+ in a few weeds and was wondering if the 168 Amax suffered from the same transonic destabilization problems as the 168 SMK's.

Thanks </div></div>

No, the boat tail on the amax is longer and it does not upset like the SMK. Push'em hard and rock on.

I should add that the elevation where you will will be may affect your results.

 

[Lindy]

Re: 168 Amax transonic performance???

The 168 Amax has a lower BC than the 175 SMK, so it will suffer at very long distances, but, as noted by RADcustom, it should behave better than the 168 SMK when it does go transonic. His note on altitude is relevant as well.

Thinner air is a great aid to ballistic performance which, alas, those of us down here at sea level cannot benefit from.

 

[RADcustom]

Re: 168 Amax transonic performance???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lindy</div><div class="ubbcode-body">The 168 Amax has a lower BC than the 175 SMK, so it will suffer at very long distances, but, as noted by RADcustom, it should behave better than the 168 SMK when it does go transonic. His note on altitude is relevant as well.

Thinner air is a great aid to ballistic performance which, alas, those of us down here at sea level cannot benefit from.

</div></div>

WOW, proof that a broken watch really is right twice a day.

 

[flyboy]

Re: 168 Amax transonic performance???

Appreciate the help guys.

Thanks

 

[RobertB]

Re: 168 Amax transonic performance???

I always hear that the 168 SMK sucks compared to the AMAX and 175SMK. I still shoot the 168 SMK until I run out. Can anyone tell how far until you can notice a real difference. Accuracy with mine are great but I havent shot my 308 in a while and only shot out to 600. they were fine for me at that range. From what I hear the lapua 155 and 175 SMK are great choices with the 168 AMAX next in line. What is the choice for yall fine marksmen?

 

[Lindy]

Re: 168 Amax transonic performance???

You won't notice much of a problem with the 168 SMK until you get beyond 700 or 800 yards. The problem is that the angle on the boattail is too steep, and when they get into the transonic region, they get ugly. I've seen them keyholing at 1000 yards, and falling out of the sky beyond 800 at sea level.

If you want a lighter bullet than the 175 SMK, you might try the Lapua Scenar 155 grain.

 

[GRIM]

Re: 168 Amax transonic performance???

Was at Blackwater many years ago. Shot a Rem700 .308 24" 1:12 twist barrel. Fed GMM 168 ammo. Shot a 3 round 1/2 MOA group at 800 yds that were covered by one 4" paster/pin. At 900 yds the 3 shot group opened to 1 MOA & at 1000 yds the round were keyholing. 168 SMK's fell apart after 800+ yds for me. Think the chrono was around 2650 fps at 5500' elevation or so - but can't remember for sure.

Switched to AMAX 168's since then, same rifle shoots them sub 1/2 MOA but need to take the rifle out and stretch it's legs again but the data tells me that I'll stay supersonic beyond 1050 this time. I'm gonna stick with the AMAX 168s' for sure.

 

[mgd45]

Re: 168 Amax transonic performance???

Shot my 168 grain AMAX's to 1000 yards recently.......by the time I narrowed down my windage & elevation, my last 4 shots measured 5.490".....with no keyholing....

 

[Bushmaster55]

Re: 168 Amax transonic performance???

Would you mind shareing your load data, I started last year w/ 168 Amax's,46gn. 4895, had them running 2700/2725 and ended up blowing a primer and blew up the extractor and crushed the spring in a Savage 10. I was useing once fired Fed brass at the time, the only 308 I could find. I think its too soft and really think I was sold somebodys junk that was not once fired. Have started over w/ new rem brass and 175 SMK, But I really like the A-Max.

 

[mgd45]

Re: 168 Amax transonic performance???

Sure,

I'm using once fired brass, then I neck size it to give me a little more interior powder capacity....Load data:

Bullet: Hornady 168 grain AMAX
Case: Hornady TAP
Primer: CCI-200
Powder: 45.5 grains of Varget
Velocity : 2793 fps
Case Length: 2.015"

Crap....I can't remember my COAL at this moment.....I'll check my load notebook when I get home for lunch....I know I seated them a little long...


EDIT: Checked the COAL....I seated them .015" off the lands, so with the comparator on my calipers, it measures 3.250" to the bullet ogive.

 

[mikeg1005]

Re: 168 Amax transonic performance???

I got my 168gr AMAX to do 2830fps.. similar to my SMK loads w/o presure issues.

168gr AMAX
2.815" OAL
45gr. IMR 4064
CCI LRP
Hornady Match Brass trimmed to 2.005"
Out of a savage 10fp.

MIke.

 

[GRIM]

Re: 168 Amax transonic performance???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bushmaster55</div><div class="ubbcode-body">Would you mind shareing your load data, I started last year w/ 168 Amax's,46gn. 4895, had them running 2700/2725 and ended up blowing a primer and blew up the extractor and crushed the spring in a Savage 10. I was useing once fired Fed brass at the time, the only 308 I could find. I think its too soft and really think I was sold somebodys junk that was not once fired. Have started over w/ new rem brass and 175 SMK, But I really like the A-Max. </div></div>

This rifle just plain old doesn't want to shoot 175's of any kind. Tried to get it to but it just won't shoot them like the 168's.

New Winchester brass (trimmed to 2.005" & FL sized which just cleans up the opening & makes it round-ish).
Fed 210M primer
168 AMAX
43.0 grains 8202 powder
COAL - 2.805"
Shooting it out of a Rem700 .308 with an old 24" winchester hammer-forged barrel at 2710 fps at 5500' elevation. The calculations say that I can get past 1200 yds before transitioning so that is what I made my range card out to.
Pics of 3 separate range sessions with that load in my rifle.

 

[H5N1]

Re: 168 Amax transonic performance???

I am at 361ASL here on my range. I have seen the 168Amax hit the steel sideways via member NHD.

As said above I've seen them work good to 800, but it becomes a crap shoot if they are point first or hit the plate at 1k.

IMHO nothing says "I don't shoot that far" like an 168gr.

 

[RobertB]

Re: 168 Amax transonic performance???

What is the transonic speed? Does anyone know of the top of there head?

 

[Niles Coyote]

Re: 168 Amax transonic performance???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">What is the transonic speed? Does anyone know of the top of there head? </div></div>

That will depend entirely on your local weather conditions and altitude at the time of the shot. But JBM ballistics can predict where it will be if you put in the info. Byran Lintz's book "Applied Ballistics for Long Range Shooting" goes into great detail on the subject if you are interested see here http://www.appliedballisticsllc.com/index_files/Book.htm

You want to stay above mach 1.2 if I remember right to be stable with the 168. For me thats usually around 775 to 825 yards.

 

[High Binder]

Re: 168 Amax transonic performance???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GRIM</div><div class="ubbcode-body">

Switched to AMAX 168's since then, same rifle shoots them sub 1/2 MOA but need to take the rifle out and stretch it's legs again but the data tells me that I'll stay supersonic beyond 1050 this time. I'm gonna stick with the AMAX 168s' for sure. </div></div>

My AMAX load has me at avg.2755 FPS and goes trans-sonic at 1300yrds. That's also at 5000 Alt./Den.

 

[High Binder]

Re: 168 Amax transonic performance???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">What is the transonic speed? Does anyone know of the top of there head? </div></div>

That mostly depends on your alt/density. I'm at 5000 feet and it's 1132.09 FPS here, it'll be a bit lower (slower) for you at your alt.

 

[savageshooter623]

Some may say that this is a fantasy, but has anyone tried pushing these out to a mile? I know people are running the 175 SMK because of its stability. I reload and am thinking about trying to replicate superformance match load from Hornady because im shooting 100 yard groups similar to those posted above. Call me crazy, but I love doing things that most people think is impossible.

 

[RobertB]

Shot my 20" 308 with 175 SMK's out to 1300 yds yesterday with very good results, I was very surprised. I wasn't expecting near the accuracy we had. Just shooting rocks on hillsides in Kansas in 10-20MPH winds. 168 AMAX is my other fav out of it.

 

[hornet shooter]

I have shot the 168gr AMAX out to 1200yd at 950ft asl. It has done great for me with no key holes out to 1200yd. It took 15.3mils last weekend to tag steel at 1200yd.