178 amax / 175 SMK

[KeithR41]

Bought a box if 178 Amax for giggles just to try them. How do they stack up against the 175 SMK, which is my current load?

 

[427Cobra]

Re: 178 amax / 175 SMK

Same charge and play with seating depth, .010 off the lands works great in my stick.

 

[vman]

Re: 178 amax / 175 SMK

Very similar.

 

[Bob L Swagger]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KeithR41</div><div class="ubbcode-body">Bought a box if 178 Amax for giggles just to try them. How do they stack up against the 175 SMK, which is my current load? </div></div>

Just curious, What is the current load you are using? I just bought 2 boxes of them also. Thinking of stepping up from the 168's I've been shooting for years. Looking forward to shooting the .308 at 1000 yards and I hear the 168's wont make it like the 178's will.

 

[Michael]

Re: 178 amax / 175 SMK

The 168 SMK in some loads/twists will make 1k with ease but the wind fight will discourage you.
The 168 Amax will do 1k in good form, equal to the 175smk. The 178 Amax will make you wonder why you ever shot smk's as far as wind deflection goes.
Having said all that, the 190 smk in the 308 handily beats all of the above.

 

[Bob L Swagger]

Re: 178 amax / 175 SMK

Im shooting a 26" 1:12 twist remington 700P so i don't think the 190 will stabilize all that well from that barrel. I think the heaviest I can go is 178.

 

[Nessal]

Re: 178 amax / 175 SMK

I have since moved away from 175SMK and settled on the 178 AMAX. Actually, the only bullets I use these days are the Amax and Scenars.

 

[cooper_257]

Re: 178 amax / 175 SMK

175 smk shoot great with a jump. in my gun the 178amax did not like the jump keeping them at mag length

 

[leadbullet]

Re: 178 amax / 175 SMK

in my 1-12 kreiger, the 175 SMK and 178amax, with the same charge shoot to the exact same POI at 600yds. hope this helps.

 

[Asm1]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bob L. Swagger</div><div class="ubbcode-body">Im shooting a 26" 1:12 twist remington 700P so i don't think the 190 will stabilize all that well from that barrel. I think the heaviest I can go is 178. </div></div>

1-12 twist 190's will do well 208's-210's are no problem eather...I have the t shirt for 10k rounds easy..

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ASM1</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bob L. Swagger</div><div class="ubbcode-body">Im shooting a 26" 1:12 twist remington 700P so i don't think the 190 will stabilize all that well from that barrel. I think the heaviest I can go is 178. </div></div>

1-12 twist 190's will do well 208's-210's are no problem eather...I have the t shirt for 10k rounds easy.. </div></div>

I could never get SMK190s, SMK200s or SMK210 to work well for me in my 1:12 24" factory Remington barrel even when new so I gave up. I had pressure signs before I found solid stablization of SMK190 and SMK210s. What MV are you loading to?

The SMK175 and AMAX168 are shooting better past 900yards for me for some reason. I run moderate loads, AMAX168 at 2750FPS and SMK175s at 2615FPS and they both seem to shoot well to 1,000yards though I dial 1 mil rad less elevation for the AMAX168s. Wind is about the same, maybe favoring the AMAX168 but only just maybe.

 

[mavrick10_2000]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bob L. Swagger</div><div class="ubbcode-body">Im shooting a 26" 1:12 twist remington 700P so i don't think the 190 will stabilize all that well from that barrel. I think the heaviest I can go is 178. </div></div>

Folks are shooting the 208 AMAX without issue in that same barrel.

 

[bohem]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mavrick10_2000</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bob L. Swagger</div><div class="ubbcode-body">Im shooting a 26" 1:12 twist remington 700P so i don't think the 190 will stabilize all that well from that barrel. I think the heaviest I can go is 178. </div></div>

Folks are shooting the 208 AMAX without issue in that same barrel. </div></div>

Depending upon local atmospheric pressure. MontanaMarine is shooting them successfully in a region where the average pressure is around 26 inHg, I can tell you from experience that a 208 won't stabilize at sea level from a 12 twist.

 

[tomcatfan]

Re: 178 amax / 175 SMK

I actually just did a test yesterday with 175 smk's and 178 amax's. I used the same load, same brass, same primer, same seating depth for both the smk's and the amax's. To my suprise the groups were about the same, but the amax's shot about an inch higher at 100 yds when compared to the smk's.

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Savage 10fp</div><div class="ubbcode-body">I actually just did a test yesterday with 175 smk's and 178 amax's. I used the same load, same brass, same primer, same seating depth for both the smk's and the amax's. To my suprise the groups were about the same, but the amax's shot about an inch higher at 100 yds when compared to the smk's. </div></div>


What were you testing? Same seating depth of what? COAL? Ogive? What MVs did you get? A whole inch at 100 yards? Not likely unless you were way off in powder charge, SMK175 and AMAX178 bullets perform virtually identically in the real world if they leave the barrel at the same velocity (as long as the MV is under 2800fps anyway) with a typical commercial chamber.

The SMK168 vs. the AMAX168 is another story. In testing loads that have identical MV AMAX168s have a noticeable wind drift and trajectory advantage in the field which also shows up in calculated external ballistics. The AMAX bullet ogive is different which is part of where the AMAX gets it's BC edge and this makes testing using COAL a poor comparison due to the differences in MV when using COAL as the seating standard.

 

[Notso]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Savage 10fp</div><div class="ubbcode-body">I actually just did a test yesterday with 175 smk's and 178 amax's. I used the same load, same brass, same primer, same seating depth for both the smk's and the amax's. To my suprise the groups were about the same, but the amax's shot about an inch higher at 100 yds when compared to the smk's. </div></div>
I shoot both alot but I load them to different COALs because of the longer 178. I do load them to the same ogive point however. By doing that, I have a COAL of about 2.820 for the 175 SMKs and 2.870 for the 178 AMAXs. MV and POI are about identical with the 178s usually being just a shade slower, like 10 FPS.

I'm betting that if you're using the same seating depth for both bullets on your seating die - you're getting higher pressures and maybe a bit more MV - hence the higher (flatter) group.

 

[LoneWolfUSMC]

Re: 178 amax / 175 SMK

The wind was gusting pretty good, but this was my workup the other day.

178gr Hornady BTHP
RE-15
Federal Gold Metal Match Brass trimmed to 2.00" and FL Sized
Federal GM210M Primers
Seated to 2.85"

There is some promise in there.

 

[jbell]

Re: 178 amax / 175 SMK

I have recently gone to the 178 A-MAX from the 175 SMK and like them. I am loading them 0.005 off the lands in Lapua brass with 44.5g of Varget lit by a 210GM. Out of my TRG 26" I am getting 2690 +/- fps at 35f or colder. They seem to do well at distance and the short range accuracy is close to the 175g load which is most accurate at 2580 fps. Ill have to watch it when it warms up but so far so good.

I do have a thread in the reloading section about the inconsistant ogive to base length I have found with this current lot of 178 A-MAX, FYI.

 

[Hookman]

Re: 178 amax / 175 SMK

Looks like your rifle loves 45.5 of RE-15.

 

[Notso]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">The wind was gusting pretty good, but this was my workup the other day.

178gr Hornady BTHP
RE-15
Federal Gold Metal Match Brass trimmed to 2.00" and FL Sized
Federal GM210M Primers
Seated to 2.85"

There is some promise in there.
</div></div>
Is that with the new AAC-SD budget build?

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">The wind was gusting pretty good, but this was my workup the other day.
[Photos SNIPPED]
178gr Hornady BTHP
RE-15
Federal Gold Metal Match Brass trimmed to 2.00" and FL Sized
Federal GM210M Primers
Seated to 2.85"

There is some promise in there.
</div></div>

Hi LoneWolf,

I'm waiting for a couple boxes of Hornady 178grain Match bullets to show up and I am wondering where the ogive is on the Hornady 178grain Match compared to 175grain SMKs? Is it set back like an AMAX or closer to the front like an SMK? The Hornady 178grain Match bullets on paper appear to have an distinct advantage over 175grain SMKs so I wanted to try them before loading up another large batch of 175grain SMKs.

One last thing, how fast are you shoving your 178grain Hornady Match bullets?

 

[LoneWolfUSMC]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body">
Is that with the new AAC-SD budget build? </div></div>

No, this was the AE MkII.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">I am wondering where the ogive is on the Hornady 178grain Match compared to 175grain SMKs? Is it set back like an AMAX or closer to the front like an SMK?</div></div>

The ogive seems to be set back a bit. I have not compared them to 178 Amax or even 175 Sierras up close.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">The Hornady 178grain Match bullets on paper appear to have an distinct advantage over 175grain SMKs so I wanted to try them before loading up another large batch of 175grain SMKs.</div></div>

I have 170 left after the workup. I am hoping to get some loaded up this weekend and see how they do. I am going to be really interested to see how the published BC tracks with real data. The bullets themselves are cheaper than 175 Sierras, so even if the ballistics are a wash if they are accurate, they will be my "go-to" bullet.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">One last thing, how fast are you shoving your 178grain Hornady Match bullets?</div></div>

Hoping to get about 2700 fps out of them. That will give me some decent ballistics but still be tame enough to work in other rifles. I don't have my notebook in front of me to check what the most accurate nodes chronographed at.

 

[LoneWolfUSMC]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hookman</div><div class="ubbcode-body">Looks like your rifle loves 45.5 of RE-15. </div></div>

The surprise was that 43.0gr was the most accurate load and it's the same charge I use for my 175 SMKs. However I would like something a little warmer and the 45.5gr node may be a little more tolerant to slight variances.

Sorry to sidetrack, I just realized that this was a thread about the AMAX not the BTHP.

 

[m1ajunkie]

Re: 178 amax / 175 SMK

I haven't had a chance to chrony my loads yet, but my 175gr smk load shoots 1 moa higher at 100yds than my 178amax load. This trend continues to 600yds where the 178amax takes 15.5min to be zeroed and the 175's take about 14.75min to be zero.

Both loads are over 43.5gr varget, amax is at 2.81" and the 175smk is at 2.80", lc lr brass, wlr primers. I was under the impression that the heavier bullets should shoot just a hair lower than the lighter, is this correct? At least the data on my rifle supports this, and I will be able to chrony these loads thursday to see what kind of velocity I am getting from my 20" barrel.

 

[YAOG]

Re: 178 amax / 175 SMK

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

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">I am wondering where the ogive is on the Hornady 178grain Match compared to 175grain SMKs? Is it set back like an AMAX or closer to the front like an SMK?</div></div>

The ogive seems to be set back a bit. I have not compared them to 178 Amax or even 175 Sierras up close.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">The Hornady 178grain Match bullets on paper appear to have an distinct advantage over 175grain SMKs so I wanted to try them before loading up another large batch of 175grain SMKs.</div></div>

I have 170 left after the workup. I am hoping to get some loaded up this weekend and see how they do. I am going to be really interested to see how the published BC tracks with real data. The bullets themselves are cheaper than 175 Sierras, so even if the ballistics are a wash if they are accurate, they will be my "go-to" bullet.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">One last thing, how fast are you shoving your 178grain Hornady Match bullets?</div></div>

Hoping to get about 2700 fps out of them. That will give me some decent ballistics but still be tame enough to work in other rifles. I don't have my notebook in front of me to check what the most accurate nodes chronographed at. </div></div>

LoneWolf,

Regarding the Hornady 178grain Match ogive it seems like a hybrid sort of mixing the SMK and AMAX ogive. When I get them I'll use my Redding instant indicator and compare all three bullets. Your thinking is tracking with mine on the Hornaday match BC and cost, as long as the Hornady match are as accurate as the SMKs why not use the less expensive bullets? WOW 2700fps? that's a bit hot for a 178grain bullet isn't it? With 175grain SMKs I'm topping out about 2630fps with H4895 in 55-65F degrees. I'm going to try some Russian primers and a bit more power. I'm also going to try IMR4895 and IMR 8208XBR with the Russian primers to see if I can get a bit more velocity out of them.

Thanks for the reply.

 

[tomcatfan]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Savage 10fp</div><div class="ubbcode-body">I actually just did a test yesterday with 175 smk's and 178 amax's. I used the same load, same brass, same primer, same seating depth for both the smk's and the amax's. To my suprise the groups were about the same, but the amax's shot about an inch higher at 100 yds when compared to the smk's. </div></div>
I shoot both alot but I load them to different COALs because of the longer 178. I do load them to the same ogive point however. By doing that, I have a COAL of about 2.820 for the 175 SMKs and 2.870 for the 178 AMAXs. MV and POI are about identical with the 178s usually being just a shade slower, like 10 FPS.

I'm betting that if you're using the same seating depth for both bullets on your seating die - you're getting higher pressures and maybe a bit more MV - hence the higher (flatter) group. </div></div>

My bad. Your right on. I was using the same seating depth based on COAL for both bullets. I should have specified in my post. I haven't gotten my set up squared away to measure seating depth based on the ogave yet, but I'm working on it.

 

[tomcatfan]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: m1ajunkie</div><div class="ubbcode-body">I haven't had a chance to chrony my loads yet, but my 175gr smk load shoots 1 moa higher at 100yds than my 178amax load. This trend continues to 600yds where the 178amax takes 15.5min to be zeroed and the 175's take about 14.75min to be zero.

Both loads are over 43.5gr varget, amax is at 2.81" and the 175smk is at 2.80", lc lr brass, wlr primers. I was under the impression that the heavier bullets should shoot just a hair lower than the lighter, is this correct? At least the data on my rifle supports this, and I will be able to chrony these loads thursday to see what kind of velocity I am getting from my 20" barrel. </div></div>

I was getting the same results loading my rounds to the same COAL.

 

[BCP]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">With 175grain SMKs I'm topping out about 2630fps with H4895 in 55-65F degrees. I'm going to try some Russian primers and a bit more power.</div></div>

Maybe try a slower powder like varget or 4064? If it's doing what you want I wouldn't worry about it though.

Also, your chrono could be lying. I know my chrono lies to me.

Once I did the math on the range I found that my 2600fps 223 load was more like 2700 and my 2500fps 308 load was 2550. Both 18" gas guns by the way.

edit: i shot a bunch of 175smks and could never get them to stabilize the way I wanted them to. 178amax just seems to be more consistent.

 

[Notso]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Savage 10fp</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Savage 10fp</div><div class="ubbcode-body">I actually just did a test yesterday with 175 smk's and 178 amax's. I used the same load, same brass, same primer, same seating depth for both the smk's and the amax's. To my suprise the groups were about the same, but the amax's shot about an inch higher at 100 yds when compared to the smk's. </div></div>
I shoot both alot but I load them to different COALs because of the longer 178. I do load them to the same ogive point however. By doing that, I have a COAL of about 2.820 for the 175 SMKs and 2.870 for the 178 AMAXs. MV and POI are about identical with the 178s usually being just a shade slower, like 10 FPS.

I'm betting that if you're using the same seating depth for both bullets on your seating die - you're getting higher pressures and maybe a bit more MV - hence the higher (flatter) group. </div></div>

My bad. Your right on. I was using the same seating depth based on COAL for both bullets. I should have specified in my post. I haven't gotten my set up squared away to measure seating depth based on the ogave yet, but I'm working on it. </div></div>

What seating die are you using? I use the Redding Comp micro seating die and using an ogive tool, I found that to get roughly the same ogive spot for both bullets, I had to seat the 178s to roughly .05 longer than the 175s. Doing that, I get almost the exact same MVs and POI. Very close anyway.

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BCP</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">With 175grain SMKs I'm topping out about 2630fps with H4895 in 55-65F degrees. I'm going to try some Russian primers and a bit more power.</div></div>

Maybe try a slower powder like varget or 4064? If it's doing what you want I wouldn't worry about it though.

Also, your chrono could be lying. I know my chrono lies to me.

Once I did the math on the range I found that my 2600fps 223 load was more like 2700 and my 2500fps 308 load was 2550. Both 18" gas guns by the way.

edit: i shot a bunch of 175smks and could never get them to stabilize the way I wanted them to. 178amax just seems to be more consistent.

</div></div>

I like to test one thing at a time so I can track what I've got. I've got an 8lb. jug of Varget along with IMR4895 and IRM8208XBR powders sitting on the shelf. I just have not managed to get around to testing them all yet with the various primers I have.

I'm pretty confident in the Kurzzeit PVM21 chronograph we're using it reads consistently and reliably. I have seen never it miss a shot. As far as the numbers goes the MVs the PVM21 gives us match up very well with calculated drops using various ballistics programs so I doubt the chrono is an issue.

I've found that with some bullets you need to get past 100yards before the bullets stablize well. I shoot at ASR and can shoot paper to 300yards and steel out to 600yards so you can see the difference on paper. I have seen some SMK168s improve significantly at 200 yards in a 12 twist barrel where AMAX168s 2,700+fps are like lasers from 100-1,000 yards.

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Savage 10fp</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Savage 10fp</div><div class="ubbcode-body">I actually just did a test yesterday with 175 smk's and 178 amax's. I used the same load, same brass, same primer, same seating depth for both the smk's and the amax's. To my suprise the groups were about the same, but the amax's shot about an inch higher at 100 yds when compared to the smk's. </div></div>
I shoot both alot but I load them to different COALs because of the longer 178. I do load them to the same ogive point however. By doing that, I have a COAL of about 2.820 for the 175 SMKs and 2.870 for the 178 AMAXs. MV and POI are about identical with the 178s usually being just a shade slower, like 10 FPS.

I'm betting that if you're using the same seating depth for both bullets on your seating die - you're getting higher pressures and maybe a bit more MV - hence the higher (flatter) group. </div></div>

My bad. Your right on. I was using the same seating depth based on COAL for both bullets. I should have specified in my post. I haven't gotten my set up squared away to measure seating depth based on the ogave yet, but I'm working on it. </div></div>

What seating die are you using? I use the Redding Comp micro seating die and using an ogive tool, I found that to get roughly the same ogive spot for both bullets, I had to seat the 178s to roughly .05 longer than the 175s. Doing that, I get almost the exact same MVs and POI. Very close anyway. </div></div>

Exactly! I'm also using Redding Comp dies and seaters. The only problems with 178AMAXs seated to the same ogive dimension as factory FGMM loaded with SMK175s is you have inadequate case neck area holding the AMAX178 bullet and the assembled rounds won't fit in the mag. well of my rifle. While this works for single shot loading this is not a practical field load.

 

[Notso]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">Exactly! I'm also using Redding Comp dies and seaters. The only problems with 178AMAXs seated to the same ogive dimension as factory FGMM loaded with SMK175s is you have inadequate case neck area holding the AMAX178 bullet and the assembled rounds won't fit in the mag. well of my rifle. While this works for single shot loading this is not a practical field load.

</div></div>
I'm not sure I agree with the "not enough case neck holding the bullet". I shoot them this way all the time feeding from an AI mag and never had a problem with setback or anything else.

But yes, unless you're shooting AI mags or similar - rounds loaded to 2.860 won't load from an internal mag.

 

[YAOG]

Re: 178 amax / 175 SMK


LoneWolf,

Did you get a chance to shoot your Hornaday 178 Match rounds? Is so how did they shoot? I got mine and was shocked to see that the Hornaday 178 Match bullets are nearly 1/10" longer than SMK175s. I'm not sure how to load them or where to start because they are so much longer and reduce the case capacity so much. Any suggestions? I have IMR4895, H4895, IMR8208, Varget powders and CCI 200 and Wolf LR primers on my bench.

 

[Rob01]

Re: 178 amax / 175 SMK

They didn't reduce any useful case capacity for me. I loaded them with the same loads at my AMAX and SMK and there was plenty of room. Had no problems with 45grns of Varget in the case under them but found the most accurate load at 44grns.

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rob01</div><div class="ubbcode-body">They didn't reduce any useful case capacity for me. I loaded them with the same loads at my AMAX and SMK and there was plenty of room. Had no problems with 45grns of Varget in the case under them but found the most accurate load at 44grns. </div></div>

Hey Rob01,

Interesting stuff to know. Did you get a chance to chrono your Hornady Match 178 loads? There is still room in the case but the Hornady Match 178 bullet's base will protrude into the case almost a 1/10" of an inch more than an SMK175 bullet.

I have a good SMK175 load for my Rem700; RP brass, CCI200 primer, 42.5 grains of H4895, base to ogive height 2.227", 2.810" COAL, 2,630FPS. This is a near max load but still shoots well. Maybe I'll dial it back down a grain, use some of the softer hitting Russian primers and put some Hornady Match 178s on top to try out in a day or two.

Thanks!

 

[96C]

Re: 178 amax / 175 SMK

Tag - looking to switch to 178.

How do you think they will fly from a 20" Rem factory 1:12" barrel?
I'm running 168 AMAX currently and they're doing well... Do you think 1:12" 20" will run into stability issues?

Most shooting is about 200-600 meters ASL.

 

[Rob01]

Re: 178 amax / 175 SMK

I am getting 2730fps from my 44grns of Varget load. Not sure if you have a mag or factory bdl set up but you can load out to 2.825" usually in a Rem and still have it feed from the internal mag and with the long throats on Rems that's not a problem so you can seat it out more if you wanted.

96C, only one way to find out

Seriously I don't think there will be a problem.

 

[96C]

Re: 178 amax / 175 SMK

True that, what could possibly go wrong?!

Internal mag with a Williams bottom metal, clean and simple.

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 96C</div><div class="ubbcode-body">Tag - looking to switch to 178.

How do you think they will fly from a 20" Rem factory 1:12" barrel?
I'm running 168 AMAX currently and they're doing well... Do you think 1:12" 20" will run into stability issues?

Most shooting is about 200-600 meters ASL. </div></div>


Hi 96C,

If most of your shooting happens inside 600m stick with your 168 AMAX rounds. I had no problem getting 168 AMAXs to go faster than 2700FPS with no pressure signs with a well under max powder charge too.

For 168 AMAX rounds I use commercial RP brass with uniformed primer holes and pockets, cases trimed to 0.005" under max SAAMI .308Win case specs and set the case shoulders to headspace at 0.002" and 0.001" neck tension. The 168 grain AMAX bullets were seated with a base to bullet ogive height of 2.190" yielding a COAL of 2.810" and charged with 43.1 grains of H4895. These rounds shoot very well at about 2,730FPS all the way out to 1,000 yards.

The same cannot be said for the 178 AMAX bullets using the same components. With the highest powder charge I could use was 2,550FPS with mild pressure signs. Initially I used the same case set up and the same base to ogive height which gave me the same COAL of 2.810" so then I tried setting the bullets farther out to get back some of the case volume I lost due to the slightly longer ogive to base dimension of the 178 AMAX bullets. This slightly improved this round but I cannot seat the bullets far enough out to reproduce the 168 AMAX load's case volume because I cannot fit a 2.860" COAL in my Rem700 BDL internal magazine. So I got to 2,570FPS by moving the bullet out to a COAL of 2.830" but this round does not shoot well in my rifle and is an over-max load at least in the Hornady reloading manual anyway.

The most interesting thing about the 168 and 178 grain AMAX bullets is that there is not a lot of difference between them in the field. The 168 AMAX performs as well as the 175 grain SMKs which the 178 AMAX preproduces perfectly. Dimensionally the 168 AMAX is nearly identical to the 175 SMK. But I could not push the 175 SMK as fast (best I could get and still shoot well was 2,600FPS vs. 2,730FPS) as a 168 grain AMAX and they end up being about the same basically all of the way out to 1,000 yards with the 168 AMAX shooting a bit flatter with less flight time to target.

So unless I can find a way to make the 178 grain Hornady Match bullets to shoot well and move at least 2,600FPS the 168 grain AMAX will still be the winner. Even if I can get the 178 grain Hornady Match to move and shoot well at 2,600FPS the 168 AMAXs will still be the equal of the 178 Hornady Match out to 700 yards.

Makes me wonder why I bother and don't just be happy plugging along with the 168 AMAX loads I have. But it does give one something to do doesn't it? 8^)

 

[Rob01]

Re: 178 amax / 175 SMK

Try some Varget.

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rob01</div><div class="ubbcode-body">I am getting 2730fps from my 44grns of Varget load. Not sure if you have a mag or factory bdl set up but you can load out to 2.825" usually in a Rem and still have it feed from the internal mag and with the long throats on Rems that's not a problem so you can seat it out more if you wanted.

<<SNIPPED>> </div></div>

Rob01,

2,730FPS with the Horny Match 178s? MAMMA! That would be a HOT performer if I could do the same in my Rem700 BDL with factory 24" Varmint barrel! Factory BDL mag, mine seems to be reliable out to 2.830" COAL so I'm going to have to play with your load and see what I can find over the Kurzzeit PVM21. Thanks again!

 

[Rob01]

Re: 178 amax / 175 SMK

Don't start with that load as it is in the midle of the recommended powder charge range of 42grn min to 45grn max. Start lower for safety.

Mine are only loaded to 2.840". That velocity is from a 26" Bartlein barrel. You might not get that much but you should be able to get in the mid 2600s pretty easy.

 

[YAOG]

Re: 178 amax / 175 SMK

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rob01</div><div class="ubbcode-body">Don't start with that load as it is in the midle of the recommended powder charge range of 42grn min to 45grn max. Start lower for safety.

Mine are only loaded to 2.840". That velocity is from a 26" Bartlein barrel. You might not get that much but you should be able to get in the mid 2600s pretty easy. </div></div>

Hey Rob01,

Oh no problem. I was going to start at 42grn and bump up 0.3 grns at a time looking for pressure issues then work back and see what I can set as a safe max charge and go from there. I've been doing this a few years and know better than to use whatever someone on the internet said worked for them even if it's a guy (like you) I think knows what he's doing. But thanks for thinking of me!

 

[AllenP]

Re: 178 amax / 175 SMK

I bought a box this morning. I did a weight experiment with 40 bullets from each box.

<span style="font-weight: bold">AMAX</span>

<span style="font-weight: bold">SMK</span>

 

[WKR]

Re: 178 amax / 175 SMK

I shoot 178 gr amax with 42.6 gr Varget, fed 210 primer in Winchester brass COL 2.835" ( 10 th off the lands ) in a savage 10 24" bbl with a MV of 2625 fps ( chrono says 2595 fps but 2625 matches jbm & shooter on the drop out 840 yds which is what I have access to for now ) this load/bullet combo shoots better than smk 168 & 175 gr at this distance, at 100 yds I can't see any difference in accuracy between the three of them, I haven't tried the 168 amax but I dont think I need to, the 178s shoot great and are very consistent.
Note: I tried a box of new lapua brass thinking it would shoot better than the Winchester, not the case in my rifle, I tried a few loads and couldn't duplicate the accuracy or ES of the Winchester brass loads.

 

[1Sg (ret)]

Re: 178 amax / 175 SMK

Tag starting to use 178 amax. been using 168 amax.I have shot 168 amax to 1000 but wind included only hit 5 out of 10.

 

[Infinity]

Re: 178 amax / 175 SMK

tag

 

[Infinity]

Re: 178 amax / 175 SMK

tag

 

[Infinity]

Re: 178 amax / 175 SMK

tag

 

[Infinity]

Re: 178 amax / 175 SMK

tag