Most common 308/ 175 grn. bolt load


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Fatelvis
March 24, 2007, 05:40 PM
I know in my M1A about 41 grains of IMR4895 under a 168 SMK is the standard 308 load that produces great accuracy in almost every M14 style rifle. But with my new Rem 5R ready to zero, I was wondering if there is a "standard" 308 Win. 175 SMK load that everyone swears by. I need a place to start ! Thanks-

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USSR
March 24, 2007, 05:49 PM
Fatelvis,

42.2gr of IMR4895 works well in a bolt gun if you are using LC brass.

Don

Fatelvis
March 24, 2007, 05:53 PM
Thanks Don, Im using Lapua brass for the bolt gun though. Should I figure Lapua brass to be the same as LC, or have more/less internal volume? Thanks-

P0832177
March 24, 2007, 06:06 PM
There are many options in addition to IMR4895.

Current M118LR is loaded with non-cansister grade of RL15 and 175gr SMK, as is FGM in both 168 and 175 versions. A Fed 210M primer would be a good spark to the powder.

Varget is good with 175gr SMK, CCI BR2 primer works best.

USSR
March 24, 2007, 08:38 PM
Lapua brass has just a little more case capacity than LC. Anything between 42.2gr and 42.5gr should work fine with IMR4895. As P0832177 said, Varget and RL15 are good choices also.

Don

hagar
March 24, 2007, 08:49 PM
I shoot 44 grains of Varget with Winchester or Lapua cases.

SlamFire1
March 24, 2007, 09:31 PM
Start at 40.5 grains of IMR 4895 and I quit at 41.5. I was using LC brass and WLR, OAL .LT. 2.800". If you have a chronograph keep track of your velocities. If memory is correct, white box match ammunition with a 174 FMJ was about 2550 fps. I would keep under 2600 fps. It will stay supersonic at 1000 yards. I have shot this load out to a 1000 and did horrible, but it was not the bullet's fault. I shot it 600 yards a good number of times and did outstandingly.

Why you don't see any "standard" loads with the 175 is that Sierra came out with this bullet just as the M1a was being displaced by the AR as a target rifle. The 175 would have probably been the "standard" bullet with a couple more years on the firing line. It is an excellent bullet.

dmills
March 24, 2007, 09:40 PM
Interesting thread. I have been using the 168 SMK with R-15 and Varget with good results with R-P cases (no more of those, thank you) and Win. I have a batch of LC Match once fired on the way. I'll give the 175s a try.

Fatelvis
March 25, 2007, 01:09 PM
Ive been reading alot lately about RL15 showing temperature sensitivity, so I think I'll be trying Varget, and of course IMR4895.

30Cal
March 26, 2007, 03:19 PM
I shoot it with 42.5gr IMR4064 in a LC case. It's a little hard on the gun.

Ty

Sam Adams
June 22, 2007, 02:51 PM
Has anybody tried substituting the 178 AMAX for the 175 SMK? The ballistic coefficient is about the same at the velocity that this would be fired at in a .308 (.495 for the AMAX vs. .496 in the SMK from 1800 FPS to 2800 FPS). Yes, I know, these are different bullets - that's why I ask the question.

I'd be very interested in hearing about anyone's results with the 178s.

30Cal
June 22, 2007, 04:34 PM
I suspect the 178 has a longer bearing surface than the 175, so I'd probably back down by 1.5-2grs and see what that gets you.

Ty

Sunray
June 22, 2007, 04:44 PM
There's no "standard" load for any rifle. You must work up a load your rifle will shoot well. You will find that IMR4064 gives more consistent accuracy with either 168 or 175 grain match bullets than IMR4895. Load for the bullet weight not who made it. 175's give better accuracy at ranges past 600 yards. 168's for up to 600.

USSR
June 22, 2007, 07:44 PM
Sam,

Here are my loads using the 178gr AMax. Please note, these loads use Hornady Match brass which has a larger case capacity than most brass (except perhaps Winchester). Rifle is FN SPR, 1st Gen Model with 26" barrel.

Hornady Match Brass
178gr AMax
Fed 210M primer
45.5gr Varget
2.840" OAL
2747fps

Hornady Match Brass
178gr AMax
Fed 210M primer
45.9gr RL15
2.840" OAL
2746fps

Hornady Match Brass
178gr AMax
Fed 210M primer
48.0gr N550
2.840" OAL
2754fps

The goal of my load development was to find velocities in the 2750fps range, as this is considered a safe, performance load with 175/178gr bullets.

Don

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