.308WIN Load Development... Potential!

[Saluki91]

MODS - I'm unsure where to ask this. It may be better suited in the Rifle forum... if so, please relocate.

I recently loaded up some LC take-down cases with 168gr SMK and BL-C(2) with the intent of getting my scope and rifle on paper from 200 yards. The rifle is a Kleinguenther K15. I assume the Leopold Vari-X III 3.5-10X scope is late 70's/early 80's vintage, as that is when the rifle was purchased. My grandfather was the original owner, and didn't shoot it after 1983-1984.

My load for this was 45gr of BL-C(2) with the 168gr SMK seated to 2.800"

Given that this was merely a "safe" load to get the scope looking in the proper area code, I was very pleasantly surprised with the results, and am now excited to see just what this rifle is capable of.

My Questions:
1 - Of the powders in my stash, the following have loads published for 168gr SMK:
IMR4064, AA2520, BL-C(2), AA2230, Norma 202
I would appreciate any first hand experience with these that you care to share - specifically which produced the most accurate loads for you at distances up to 750 yards (that is where our range maxes out). If it helps, I have LC and Norma brass.

2 - In addition to 168gr SMK, I have some 175gr bullets from American Reloading marketed as "Terminal Match HPBT". Please share any experience you have with these as well. Does he word "match" in the title indicate a bullet with similar properties to SMK, or should I use these as plinking fodder? The bullets can be found here - https://americanreloading.com/en/30-caliber-308/2931-308-175gr-terminal-match-hpbt-new-250ct.html

3 - Finally, how much should I temper my expectations with this rifle and scope? Assuming I do my part, can I expect it to consistently shoot 1 MOA or better from 200 yards? How far out can I push it before tight groups become more a matter of luck than skill?

As always - Thank you very much for your input and guidance!

 

[Charlie98]

IMR4064 for the win, with either the 168grn SMK (what I load for my 24" Savage...) or the 175's (what I plan to work on next.) I have shot my Savage out to 700yds with good success.

I would probably start with the Norma brass... with a commercial case, there is likely more case volume, so you will have a slightly better potential for higher velocity... and you will need it at 700yds.

 

[Nature Boy]

Finally, how much should I temper my expectations with this rifle and scope? Assuming I do my part, can I expect it to consistently shoot 1 MOA or better from 200 yards? How far out can I push it before tight groups become more a matter of luck than skill?

Luck might play a part in one shot vs the next but it won’t have a factor over a larger sample size.

Assuming you find the most accurate load for your rifle given the components you have on hand, how good are your rifle handling mechanics and wind reading skills?

 

[The Glockodile]

IMR 4064 and Hodgdon Varget are the good old reliables as far as .308 Winchester in 168 and 175gr are concerned...

Norma brass would probably be preferable. Unless from M118LR, Lake City Brass is more often than not a garbage in, garbage out proposition...

 

[Saluki91]

Luck might play a part in one shot vs the next but it won’t have a factor over a larger sample size.

Assuming you find the most accurate load for your rifle given the components you have on hand, how good are your rifle handling mechanics and wind reading skills?

Mechanics - Passable, and improving with practice.
Wind Reading - Total Newbie... but I can't wait to learn!

 

[jmr40]

Varget is my go-to 308 powder, but 4064 works great too. I get virtually the same velocity and accuracy with the best loads with either powder. Varget only gets the nod because it is more stable and velocity changes are much less as temperature varies. I use 4064 for a lot of loads that I know will only be used at the range and prefer Varget for hunting situations.

 

[bluejay75]

I second the 4064 recommendation. In my testing it was accurate enough across the charge range to have picked any of the loads and be at or near moa. Charges came out pretty clean and easy to remember as well. 43 grains is an established match winning load with the 175s. 44 is very accurate in my rifles with 168s, with 44.5 and 41.8 being very well established optimal charge weights. I’m almost willing to bet a 6 pack that one of those 4 loads is a .40-.50 inch load if you and your gun can shoot it.

 

[Charlie98]

At the time I was shooting that 700yd target, I had 2 loads with me... the 168grn Nosler with either IMR4064 or IMR4895. IMR4895 heretofore had been my main .308 powder... but at 700yds it was throwing the bullets everywhere, IMR4064 was not. It's likely the velocity with IMR4895 was not that of the IMR4064 loads, and I probably could have worked on it a bit to get it to deliver... but why, when IMR4064 clearly had the Goods.

 

[IALoder]

IMR4064 for the win, with either the 168grn SMK (what I load for my 24" Savage...) or the 175's (what I plan to work on next.) I have shot my Savage out to 700yds with good success.

I would probably start with the Norma brass... with a commercial case, there is likely more case volume, so you will have a slightly better potential for higher velocity... and you will need it at 700yds.

What this guy said!

 

[Bfh_auto]

I second the 4064 recommendation. In my testing it was accurate enough across the charge range to have picked any of the loads and be at or near moa. Charges came out pretty clean and easy to remember as well. 43 grains is an established match winning load with the 175s. 44 is very accurate in my rifles with 168s, with 44.5 and 41.8 being very well established optimal charge weights. I’m almost willing to bet a 6 pack that one of those 4 loads is a .40-.50 inch load if you and your gun can shoot it.

44.0 of IMR 4064 and a seating depth test is all I do with 168s.
It's given such good results I don't bother with anything else.

 

[dh1633pm]

I found good results with IMR4895. Also AA2520, but sometimes hard to find. Varget and IMR4064 didn’t work out as well for me. Didn’t try RL15. Bottle too tall to fit on my powder shelf (just being honest). So my can of match ammo is all 4895.

 

[Slamfire]

I have shot kegs of IMR 4064 through 308 bolt guns, less amount through my M1a’s. I am more of a fan of IMR 4895/H486/AA2495 in the 308 Win, but can’t say there is any real problem with IMR 4064 other than it is long grained.


I did some testing over a chronograph, and this is about as fast as I would push a 150 or 168 grain bullet.


150 Sierra SP BT 44.0 grs IMR 4064 weighed IMI brass CCI200 LC90 OAL 2.760"
30 April 2008 T = 80 °F

Ave Vel = 2749
Std Dev = 14
ES = 47
High = 2777
Low = 2730
N = 10

v.good accuracy, no increased effort on bolt lift

With a 168 I would not go over 42.5 grains IMR 4064 with a 168/165 grain bullet

168 Nosler 42.0 grs IMR4064 Lot2449 thrown LC90 CCI#34 OAL 2.750"
27-Nov-06 T = 60 ° F

Ave Vel = 2594
Std Dev = 22
ES = 67
High = 2629
Low = 2562
N = 10
Prone, excellent accuracy all in 10 ring MR31C




I took my M70 PBR to CMP Talladega and blasted off some ammunition





Had some IMR 4064 loads to shoot.



Accurate Arms told me AA 2520 was blended to the same pressure curve as IMR 4895, and based on my testing, velocities are the same for the same charge weight.

When I brewed up some loads with cheap Hornady 150 FMJBT’s, the bullets shot surprisingly well for FMJ’s.



With a 168 or 165, I would start at 40.5 grains AA2520 and quit at 41.5 grains. This powder shoots very well, I did shoot up a keg or two in NRA competition, but the stuff left a lot of residue in the gas system of my M1 Garands, M1a’s, and AR15’s. But since I got it at $64.00 a keg, might as well use it. I still preferred IMR 4895.

This is AA4064, which for all intents and purposes, was slightly faster than IMR 4064. Maybe a half grain faster, and with a 175 SMK, this is what I did prone with a sling at CMP Talladega, just having fun.





I would not go over 41.0 grs IMR 4064 with a 175 SMK.

 

[denton]

AA2520 works well in the 308. However, MV will plateau as charge advances (as several other powders do). Using a magnum primer will often prevent this.

 

[joneb]

45 gr of Varget has worked well for me in a Howa 1500 sporter with a 150gr Nosler BT. I get a 5/8" group @ 100yds with 3 shots after that the barrel heats up and the groups open up to 1".
I can live with that.
I guess I should add I use Federal GM 200 and a COAL of 2.80"

 

[Slamfire]

AA2520 works well in the 308. However, MV will plateau as charge advances (as several other powders do). Using a magnum primer will often prevent this.

Its a ball powder, and I had hangfires with AA2520 in my 35 Whelen and cold weather. Ball powders require magnum level primers to reliably ignite in severed cold weather. I had great luck with Winchester large rifle, and the CCI #41 primer, which is a "magnum" primer.

 

[IALoder]

I must have read over that you had Norma 202 as well. My father in law swears by it in his savage .308 with 165 soft points. It looks to be right in line with 4064 on burn rate as well. I bet 202 is worth a try along with 4064!

 

[Charlie98]

With a 168 I would not go over 42.5 grains IMR 4064 with a 168/165 grain bullet

Interesting... that's almost the very same conclusion I came to. In my shooter notes, FGMM 168's gave me 2710fps out of my 24" Savage, as did 42grn IMR4064 (and the Nosler.) 43grn IMR4064 I noted it as absolute max twice... because of sticky bolt lift, although I don't believe the cases showed obvious pressure signs. This in commercial RP brass, not LC.

 

[Slamfire]

Interesting... that's almost the very same conclusion I came to. In my shooter notes, FGMM 168's gave me 2710fps out of my 24" Savage, as did 42grn IMR4064 (and the Nosler.) 43grn IMR4064 I noted it as absolute max twice... because of sticky bolt lift, although I don't believe the cases showed obvious pressure signs. This in commercial RP brass, not LC.

These loads are well characterized, probably millions shot down range in NRA matches. I would go ask shooters their load, and at the time for 308 shooters, the most popular powders were IMR 4895 and IMR 4064, a few IMR 3031. And then when Vihtavuori came CONUS, that was the brand du jour. The most common bullet was a 168 SMK, it was not until around the late 90's the 175 SMK came on the market. But by 1998 or so, the classic 308 bolt gun had disappeared and 223 Space Guns had taken their place in across the course shooting. The only matches I saw the 308 Bolt guns were the 600 yard matches, and then the long range shooters walked away from the mid range matches, and that was that.

 

[Bfh_auto]

Interesting... that's almost the very same conclusion I came to. In my shooter notes, FGMM 168's gave me 2710fps out of my 24" Savage, as did 42grn IMR4064 (and the Nosler.) 43grn IMR4064 I noted it as absolute max twice... because of sticky bolt lift, although I don't believe the cases showed obvious pressure signs. This in commercial RP brass, not LC.

My higher load could be from running Winchester brass. It has notably more case capacity than my Federal brass.