208 AMAX in an 18" .308?

[bm11]

I've been told that this is a good combo, but it's third hand info at this point. My shooting partners brother is friends with Scott McCree, who swears by 208's out of an 18" .308.

I'm curious if anyone is running them out of a barrel that short, what powder they are using, and what velocities they are getting. I have perused MontanaMarines thread in the Range Report forum, but I don't recall there being any data on a barrel that short. To be fair, when I read it, I wasn't specifically looking for it, so I may be wrong.

Thanks in advance for your data and input.

-Bob

 

[Timo Turl]

Re: 208 AMAX in an 18" .308?

G'day,

Not 18 but i did try it in my 24" this week at a cool 39F with Varget without much success. Worked up from 39-42gr with pressure signs at 42gr. Shot numerous rounds at 300 yds in the 39-41.5gr range and grouping was awful. I understand Varget isn't the popular choice for this bullet but I was surprised how poor it was in my rifle. To be fair i loaded them to mag length and i believe that isn't anywhere near where those who like the bullet have found the best results.

I didn't feel comfortable taking it out to 1,000 and used the 178 AMAX instead, which was very satisfactory.

Three blown on left, next two with raised primers and one on the right is fine.

I've heard too many good things about this bullet to give up but it is back to the drawing board for me.

 

[300WSM]

Re: 208 AMAX in an 18" .308?

yikes!

 

[300WSM]

Re: 208 AMAX in an 18" .308?

hope you were using a 10 twist?

 

[GardDog]

Re: 208 AMAX in an 18" .308?

My new "deer round" is a 208 gr Amax for my .308, but my data came out of a 20".

Rifle: 20" Rem 700P (1 in 12" twist)
Bullet: Hornady 208 gr AMAX
Case: Fed (2nd loading) standard case prep
Primer: Fed 210M
Powder: 43.2 grains of R-15
COL: 2.810"
Avg Vel - 2510 fps

 

[bm11]

Re: 208 AMAX in an 18" .308?

Thanks guys, keep 'em coming!

 

[eleaf]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GardDog223</div><div class="ubbcode-body">My new "deer round" is a 208 gr Amax for my .308, but my data came out of a 20".

Rifle: 20" Rem 700P (1 in 12" twist)
Bullet: Hornady 208 gr AMAX
Case: Fed (2nd loading) standard case prep
Primer: Fed 210M
Powder: 43.2 grains of R-15
COL: 2.810"
Avg Vel - 2510 fps </div></div>

I can't imagine that you're getting great performance with the 208 and a 1:12" twist. In fact, I'd be surprised if you're doing anything beyond key holing.

 

[BCP]

Re: 208 AMAX in an 18" .308?

There was a guy shooting it out of a dpms sass, I think he was using 4895 powder. Check the 308 load thread it is in there somewhere.

I thought about using 190's or 208's but I have a several hundred 178 amax sitting here and they shoot great out of my 18" so why bother.

 

[RobertB]

Re: 208 AMAX in an 18" .308?

I have a friend that does fine with 200+ grn bullets out of a 12 twist. He is shooting through a 24' though. No key holes out to 750 yds. That is as far as we shot it.

 

[MontanaMarine]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GardDog223</div><div class="ubbcode-body">My new "deer round" is a 208 gr Amax for my .308, but my data came out of a 20".

Rifle: 20" Rem 700P (1 in 12" twist)
Bullet: Hornady 208 gr AMAX
Case: Fed (2nd loading) standard case prep
Primer: Fed 210M
Powder: 43.2 grains of R-15
COL: 2.810"
Avg Vel - 2510 fps </div></div>

I can't imagine that you're getting great performance with the 208 and a 1:12" twist. In fact, I'd be surprised if you're doing anything beyond key holing. </div></div>

It may seem unlikely, but the proof is in the results. I haven't heard anyone report instability in 1/12 308Win.

These were on 1120 yard target, started at 2480 fps via RL15, in a 1/12 barrel,

 

[Saito]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GardDog223</div><div class="ubbcode-body">My new "deer round" is a 208 gr Amax for my .308, but my data came out of a 20".

Rifle: 20" Rem 700P (1 in 12" twist)
Bullet: Hornady 208 gr AMAX
Case: Fed (2nd loading) standard case prep
Primer: Fed 210M
Powder: 43.2 grains of R-15
COL: 2.810"
Avg Vel - 2510 fps </div></div>

Your C.O.L. looks good there, good enough to fit in my AR-10 mags. I may have to try this once I get home and run the #s against the 168s I currently shoot. Can't find 178s but I have like 1300+ 208grn A-max's. This thing count as an "18 incher"? LOL!

It pushes the 168grn A-max's at 2635 with 45.4 grains of Varget(suppressed). Shit, I actually seat the 168s out further than you've got those 208s!

Of course I'm not trying to reach out too far with my .308, that's what the 300WM be fur....

 

[jonaddis84]

Re: 208 AMAX in an 18" .308?

Is there even a ballistic advantage to throwing 208's that slow over say 178's or 175's? Especially at the added cost of the 208's

 

[bm11]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jonaddis84</div><div class="ubbcode-body">Is there even a ballistic advantage to throwing 208's that slow over say 178's or 175's? Especially at the added cost of the 208's </div></div>Don't know much about them, or what people are getting out of the 18" barrel, but I think the BC is around .6, hence my question.

 

[Saito]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bm11</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jonaddis84</div><div class="ubbcode-body">Is there even a ballistic advantage to throwing 208's that slow over say 178's or 175's? Especially at the added cost of the 208's </div></div>Don't know much about them, or what people are getting out of the 18" barrel, but I think the BC is around .6, hence my question. </div></div>

You best use a G7 BC of .324 for the 208 if you intend to shoot it very far. G7 negates the changing, velocity dependent, BCs of the G1 profile.

 

[Kiwi Greg]

Re: 208 AMAX in an 18" .308?

I shot the 208s in my Kimber LPT 26" barrel with RE 17 At 26-2650.
It shot around 1 moa not bad for 1-12,
It shot 155s at 1/8-1/4 moa though...pretty good for a factory rifle

You really need at least 1-10 to get the best out of the 208s

Im considering building another 308 but have been side tracked by the mighty .338s

 

[GardDog]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body">I can't imagine that you're getting great performance with the 208 and a 1:12" twist. In fact, I'd be surprised if you're doing anything beyond key holing. </div></div>

I am getting good results. I'll try to find the target page in my archive & throw up the picture. Once again, "deer round" indicated it's not been tested to 1000 yards. I shot it well and brought it in the woods last season, but had no shooter bucks present the soft target test.

 

[bm11]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Kiwi Greg</div><div class="ubbcode-body">I shot the 208s in my Kimber LPT 26" barrel with RE 17 At 26-2650.
It shot around 1 moa not bad for 1-12,
It shot 155s at 1/8-1/4 moa though...pretty good for a factory rifle

You really need at least 1-10 to get the best out of the 208s

</div></div>Yeah, I recognize that some guys are getting decent performance out of a 1 in 12, but it seems less likely to stabilize with 8 inches less barrel. I'm going to wait to develop a load for 208's until I get my 1 in 10 back from getting rethreaded.

I just wanted to collect enough intel to be able to tell if it would be worth doing.

 

[mavrick10_2000]

Re: 208 AMAX in an 18" .308?

Since in the original thread R-15 and R17 seem to be the successful powders, I'm seriously considering testing some out with H4350 and it's temp stability is very good. It's burn rate is the closest to R17.

I'm thinking about dropping the charge down .5 grain or so from some of the R17 mid range loads and do a careful test over the chrony.

 

[GardDog]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GardDog223</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body">I can't imagine that you're getting great performance with the 208 and a 1:12" twist. In fact, I'd be surprised if you're doing anything beyond key holing. </div></div>

I am getting good results. I'll try to find the target page in my archive & throw up the picture. Once again, "deer round" indicated it's not been tested to 1000 yards. I shot it well and brought it in the woods last season, but had no shooter bucks present the soft target test. </div></div>

No keyholes at 100 yards.

 

[Lowlight]

Re: 208 AMAX in an 18" .308?

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

You best use a G7 BC of .324 for the 208 if you intend to shoot it very far. G7 negates the changing, velocity dependent, BCs of the G1 profile. </div></div>

<span style="font-style: italic">*Cough* </span>
Bullshit!
<span style="font-style: italic">*cough*</span>

 

[spot69221]

Re: 208 AMAX in an 18" .308?

AIAW

44.5gr Varget (max load) seated 2.940 OAL
CCI Magnum Primer
Winchester Brass
208 AMAX
18" Krieger 1:10
2445 fps

TRG22

42.5gr Varget (close to max load)
CCI Magnum Primer
Winchester Brass
208 AMAX
26" factory 1:11
2475 fps


You need to know the atmosphere/ASL they were shot at for twist rates to be taken seriously.

There was nothing spectacular about group sizes but turns out in my applications just not enough speed to consider shooting any more of them.

 

[bm11]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: spot69221</div><div class="ubbcode-body">
There was nothing spectacular about group sizes but turns out in my applications just not enough speed to consider shooting any more of them.

</div></div>Good to know, thanks.

 

[Timo Turl]

Re: 208 AMAX in an 18" .308?

Bob have you tried these yet ?

I'm struggling with these and even if I could launch them at 2,800 at sea level, the stability factor is still under 1.1 and that falls to a lowly 1.04 with a 1:12 at 2,400. At 3,000 fps it rises to just 1.124

Is it really possible to shoot these with success at sea level out of a 308 1:12 ??

 

[djtjr]

Re: 208 AMAX in an 18" .308?

I shoot the 168s out of my short barrel 308 and the 208 out of my larger 30s. Seems like a lot of bullet to go with the 208 but if it's working for people give it a try. One thing for certain is that the amax is a great bullet no matter what just pitch the one that shoots best for your intended ourpose

 

[mikeyz250]

Re: 208 AMAX in an 18" .308?

rem 700 aac-sd 20" 1/10

working on a load with the 208 amax
Right now im at 42.6 of rl-15
win brass
cci 200 primer
2420 fsp
oal 2.820

no signs of pressure yet going to work on it some more tomorrow, maybe I can get up to 2500 fsp maybe not.

 

[mikeyz250]

Re: 208 AMAX in an 18" .308?

maxed out at 42.9 2447 increased to 43.2 no speed change blowing powder out of the end of the rifle.

 

[bm11]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TJ.</div><div class="ubbcode-body">Bob have you tried these yet ?

</div></div>No. I had some 178's on hand though, and had good results with them using 44.5 grains of Varget and a BR2 primer. Velocity was consistent and in the 2580 range, and grouped sub .5 moa at 230 yards.

Hoping to take them out to 1000 next weekend, but I have to rerun the numbers. I am at sea level as well, but the density altitude here has been in the -1400 range lately, which certainly changes the game a bit.

 

[arcticresident]

Re: 208 AMAX in an 18" .308?

Dunno if it's relevant, but i had a few tries with the 208 in my .308 with a 26" 1:10 barrel. I used Vihtavuori N550 powder, but didn't get the results i wanted, so i'll just stick to the 155 scenars, which on a good day shoots very well.

A few of my observations, for what they're worth. All shot with lapua brass:
Bullet charge weight COL(mm) V0 Temp
208 AMAX 42 grs N550 74 715 m/s 18C
208 AMAX 43 grs N550 74 730 m/s 18C
208 AMAX 43.5 N550 74 732 m/s 18C
208 AMAX 44 grs N550 74 739 m/s 18C
155 SCENAR 46 grs N150 71 825 m/s 18C

These are just some examples i shot over the chrono a sunny afternoon (in a mosquito ridden swamp!). The 155 load is thrown in there for speed comparison.

Just three shot groups, except the scenar group.

http://i.imgur.com/8EBIH.jpg

 

[paul T]

Re: 208 AMAX in an 18" .308?

Arcticresident, Have you tried 45-47g N550 Loads with Lapua brass, ccibr,208 Amax, My blaser 1 in 11 308 barrel hasnt long chamber space to seat out long but i still manage to get 50g of n550 using the berger 185g VLD seated at 2.840in, what oal are you using with your 208g amax load.

 

[arcticresident]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: paul T</div><div class="ubbcode-body"> Have you tried 45-47g N550 Loads with Lapua brass, ccibr,208 Amax, My blaser 1 in 11 308 barrel hasnt long chamber space to seat out long but i still manage to get 50g of n550 using the berger 185g VLD seated at 2.840in, what oal are you using with your 208g amax load.</div></div>

Hey Paul!
Haven't tried over 45 grains in my rifle yet, too chicken for that!

The COL is 74 mm, which should translate to roughly 2.913in. I probably won't be using the 208's anymore anyway, the rest of the batch is donated to a hunting friend with a 300WM barrel.

 

[LoneWolfUSMC]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bm11</div><div class="ubbcode-body">I've been told that this is a good combo, but it's third hand info at this point. My shooting partners brother is friends with Scott McCree, who swears by 208's out of an 18" .308.</div></div>

Just speculating, but I am betting you are going to have to run them pretty hot to keep from tossing rocks.

I get around 2600fps from the 20" AE with a compressed load of RE17. I literally can't cram any more powder in the case without it pushing the bullet back out. I may be able to switch to a faster powder and get a little more velocity, but why? Seems like trying to pull a boat with a golf cart. Sure you may be able to do it, but there are much better options.

Depending on how the 700 AAC-SD likes the 208's I may be rebarreling the other 700 to a 26" 1:10 tube so I can pull as much velocity out of the load as possible without cooking the barrel too badly.

Man stuff like this keeps making me thing a DTA SRS is a good idea.

 

[teknikallysekure]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">
Man stuff like this keeps making me thing a DTA SRS is a good idea. </div></div>

I keep finding myself at this conclusion, and lamenting the cost.

 

[Timo Turl]

Re: 208 AMAX in an 18" .308?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bm11</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TJ.</div><div class="ubbcode-body">Bob have you tried these yet ?

</div></div>No. I had some 178's on hand though, and had good results with them using 44.5 grains of Varget and a BR2 primer. Velocity was consistent and in the 2580 range, and grouped sub .5 moa at 230 yards.

Hoping to take them out to 1000 next weekend, but I have to rerun the numbers. I am at sea level as well, but the density altitude here has been in the -1400 range lately, which certainly changes the game a bit. </div></div>

I shot the 178 out to 1k last week with 45g Varget also at sea level and c35F. Loaded to 2.84 and they worked well. I don't think i can get similar performance from the 208, the drop out to 1k is going to be something in the region of 40 or more MOA and i am never going to be able to push them fast enough to compensate for the 1:12 barrel.

 

[bm11]

Re: 208 AMAX in an 18" .308?

Actually, playing around further, it's looking like I can push 155 Scenars at 2830 or better. That being said, they win on paper. With luck, I'll be able to try them in the field at 1000 yards this weekend to tell for sure, but the drop chart looks good with a .496 bc and 2830 fps, even at 30 degrees and sea level.