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Old June 10, 2013, 12:03 PM   #1
armak
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Best load choice, .308 Win, SMK 168

Hi guys,

this is my first post here, so I want to say hello from sunny Poland!

I spent half of the Sunday on a range while shooting some groups to find a sweet load for my rifle. Some of them are pretty good and I'm not sure which one to choose. Personally I think 41.8 gr would be the best, but I'm not sure if it will be fast enough for 600 meters shooting (I will be able to measure the exact velocity during my next visit on the range).

This load will be used for a target shooting with a distance up to 600 meters (I know the bullet might not be the best, but it can't be changed at the moment).

Some facts:
- groups were shot from 300 meters, the shooting conditions were moderate (slow wind, but a lot of sun -> mirage),
- rifle: Savage 12 F/TR (straight from the factory, no tuning, ~100 rounds fired up to this point), .308 cal,
- bullet: Sierra Match King 168 grain,
- powder: VV N140, primer: Federal 210M, brass: Lapua,
- OGL (length from the bottom to the ogive, measured using Hornady Bullet Comparator and Mitutoyo Caliper): 2,2185 inch,
- COAL: ~71.00 mm/2.800 inch (exact lenght depends on the bullet lenght, slightly varies),
- one big square on the targets below is 1 MOA @ 100 meters (so it's 1/3 MOA @ 300 meters).

41.6 grain

41.8 grain (ignore the flyer, I made a mistake when pulling the trigger)

42.3 grain

42.4 grain

42.7 grain


Thank you for any hints!

Last edited by armak; June 10, 2013 at 12:10 PM.
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Old June 10, 2013, 06:59 PM   #2
Bart B.
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There's not enough shots per test group to make one look most accurate to me. They're all very good. I think you need charge increments of .5 grain; .3's to small to make any noticable difference unless you're shooting 20 or mores shots per group.

I'd use the 42 grain load then shoot 10 of them into one group. Then shoot two more 10-shot groups, one with 41.5 and one with 42.5. These three will show five times better data than what you've got.

The above aside, the loads are really good and not much tweaking is needed.
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Old June 11, 2013, 07:02 PM   #3
Slamfire
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All of your groups are good, I totally agree with Bart B that you need more shots on paper to discriminate between charges.

I tested N140 fourteen years ago and it is a great powder with 168's. If you really plan to shoot 168's at 600 meters keep your velocities up. I would say you want to be at or slightly above 2600 fps, and maybe even faster if your gun/brass/primers can hold the pressures. The 168's are wind sensitive past 300 yards. I would recommend 175's SMK's or if you have access to them, the 185 Bergers.



Code:
Pre-64 M70 			
24 " Douglas Barrel 1:10 twist			
					
168 gr Sierra Match 41.5 grs AA2495 thrown, LC72 WLR	
					
30 Dec 1999 T = 58 °F				
					
Ave Vel =	2570				
Std Dev =	23				
ES =	66				
Low =	2552				
High =	2618				
N =	0				
					
168 gr Sierra Match 42.0 grs N140 wtd, Fed cases, Fed210s OAL 2.800"
					
30 Dec 1999 T = 58 °F				
					
Ave Vel =	2532				
Std Dev =	14				
ES =	48				
Low =	2511				
High =	2559				
N =	10				
					
					
168 gr Sierra Match 42.5 grs N140 wtd, Fed cases, Fed210s OAL 2.800"
					
30 Dec 1999 T = 58 °F				
					
Ave Vel =	2598				
Std Dev =	22				
ES =	78				
Low =	2563				
High =	2641				
N =	10
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Old June 12, 2013, 01:32 PM   #4
armak
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Thank you guys for the hints. I'll shoot more rounds in one group to choose the optimal load. I also plan to use SMK 175 after I run out of my current resources of SMK 168.

I was on the range today and tested few seating depths and it turned out that OAL 2,885' (OGL 2,300'') gives the best results (four of five bullets touching on 300 meters).

The tricky part is the powder - looks like all the shops can't get N140 delivered, so I must consider another one. What powder would you suggest to use with SMK 175 for .308? Preferably Hodgon/IMR (as it's quite easy to get it).

Last edited by armak; June 12, 2013 at 01:33 PM. Reason: Typo
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Old June 12, 2013, 01:49 PM   #5
Slamfire
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Quote:
The tricky part is the powder - looks like all the shops can't get N140 delivered, so I must consider another one. What powder would you suggest to use with SMK 175 for .308? Preferably Hodgon/IMR (as it's quite easy to get it).
It is going to rain recommendations because virtually any medium burning powder will produce outstanding results in the 308 Win.

The military used IMR 4895 for the majority of the 174 gr military match loads. I have shot High Master scores at 600 yards with IMR 4895 and the 175. I am currently leaning to H4895 as a replacement for IMR 4895 as H4895 is a more advanced powder. Between H4895 and Varget, it is a toss up. Varget is a little slower and is a really outstanding powder in the 308 and I have used it with 175's and 190's with excellent results at 600 and 1000 yards.

People will recommend IMR 4064 and that powder was a staple for decades, it just does not throw as well as IMR/H4895/Varget.

I have shooting buds who used IMR 4350 with 185/190 bullets in the 308 at 1000 yards. I tried but never got the velocites up high enough, but they were getting 48 grains in the case and I could never get more than 47.0 in my cases.

I do not recommend ball powders. I have not had good luck with ball powders. While they throw well they are harder to ignite, leave more residue, and in my experience, peaky. You will be blowing primers without any advanced warning of pressure indications.

I am going to add, the choice of powder is not as critical as choice of bullet. Find good bullets first.
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Old June 12, 2013, 03:06 PM   #6
armak
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Thank you for your recommendations - I'm still pretty new to realoding and I really appreciate every hint based on experience.

What about SMK 155 grain PALMA? Would you recommend them for "long range" (up to 800 meters) shooting? If so, what powder might be suitable for this bullet?

I'll consult my local shop for H4895 availability (unfortunately Varget will be available in August the earliest, so I have to choose a different one).

What would be the longest feasible distance for H4895+SMK175 pair? Would it be possible to use SMK180/SMK190 with this powder or a slower one should be used?

Thanks,
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Old June 12, 2013, 04:16 PM   #7
Slamfire
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Quote:
What about SMK 155 grain PALMA? Would you recommend them for "long range" (up to 800 meters) shooting? If so, what powder might be suitable for this bullet?
I don't shoot Palma, the guys who do use 155's at 1000 yards are pushing the things over 3100 fps. They have long barrels and high pressure loads. You can experiment, but I am not going to.


Quote:
What would be the longest feasible distance for H4895+SMK175 pair? Would it be possible to use SMK180/SMK190 with this powder or a slower one should be used
I have shot 175's at 1000 yards with H4895 and the combination works. No range within three days driving time is longer than 1000 yards, so I don't know what the longest feasible distance for 175's. I suspect it is 1200 yards. At some distance the bullet floats and gets blown all over the place by cross winds.

A very popular 600/1000 yard load, from the 70's, was a 190 SMK and 42.0 grains IMR 4064. This is an over max load, will blow primers first time in military cases (about 170 grains). Lighter cases (around 150 grains) will have a life of a couple of reloads before the primer pockets expand.

I have shot Varget at 1000 yards with 190's and it is a great powder. I have not tried H4895. You need your 190's to be close to 2600 fps and I don't know if you can get there with the faster powders.
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Old June 12, 2013, 09:13 PM   #8
Bart B.
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Palma competitors typically use 30 inch barrels and shoot those 155's out at about 3000 fps. They do not use "hot" loads.

In the heyday of the .308 Win. as a match rifle cartridge, best loads with 168's were reduced ones with 40 ot 41 grains of IMR4064 or 44 grains, same powder as a max load; a favorite with military teams' 7.62 NATO semiautos. Case weights were from 160 to 174 grains.

Bolt gunners shot 42 grains of IMR4064 under 190's in .308's and that was a maximum load, not a hot one. The favorite case for this load was a WCC58 match case weighing 150 grains. Many folks got 20 to 30 reloads per WCC58case and never had a loose primer pocket problem with that load. I've got 18 loads on one batch of those cases with that load and never had a loose promer pocket.

The above loads won most of the matches and set most of the records with 168's and 190's.

200 grain HPMK's were usually shot with 48 grains of IMR4350 with standard primers in most any case; they left at 2450 to 2500 fps from 26" barrels. Watched a 200-19X record shot at the Nationals with this load in Remington small rifle primer cases. All 20 shots went into about 4 inches at 600 yards. With aperture sights; no scope.

With today's 175 HPMK's, I'd shoot 43 grains of IMR4064 with a Wolf primer using proper tools and procedures and if it didn't shoot well, it wasn't the ammo's fault.

You have to have less than a 2/10ths grain charge weight spread with IMR4064; it seldom meteres that accurate. IMR4895 will in a good measure, but a 3/10ths grain spread of it will shoot very well. Weighed charges of IMR4064 are shoot the medium weight bullets from .308 cases the most accurate of the two powders.
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Old June 14, 2013, 03:07 AM   #9
Jimro
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If you are going to weigh each charge, just throw a tad light and trickle to desired weight.

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Old June 16, 2013, 03:13 PM   #10
HiBC
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Varget is an excellent powder for the .308 with 168 gr loads.

No need for light loads,it performs well at the upper end.

There is an old Handloader article"The Ultimate .308 Accuracy load".

The article came out after I did my work,and it agreed with my findings.

RE loader 15 is a good powder for 175 gr bullets.
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