Powder for short barrel 308

Slowbalt

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Looking for recommendations for the most appropriate powder for the following:

- Caliber is .308 Win.
- Rifle is a Tikka bolt action.
- Barrel length is 20in.
- Bullets will be 180gr Nosler Accubond.
- Would prefer it to burn completely within the barrel (not looking for a "flamethrower").
- Want to maximize the potential of the bullets, this is for a hunting load.

Thanks!
 
I never shot weight greater than 168gr, but Varget performed best in several different 308’s…. one which had a 20” barrel. My understanding is that virtually all the powder is burned by the time the bullet has moved a few inches down the barrel. It is further my understanding that “muzzle flash” is typically not related to the ignition of unburned powder.
 
I did a build for a fellow in a wheelchair that was almost the same. The action was a very nice Winchester Mod 70 short.

The barrel was a Green Mountain replacement Mini Gun Barrel, new in the white. It had a 1-12 twist rate and was 1.125 OD. Picked them up from Barry at Bits of Pieces over ten years ago.

He wanted the same thing you do. Something with lots of punch for close in shots and he could handle an old Savage 99, loaded with 180 grain bullets quite well.

Remember there isn't a lot of give, when it relates to felt recoil, from a wheel chair.

So, I checked out the velocities of the hand loads his brother had made up for the Savage 99, which was a take down whoes barrel had been cut down to 19 inches.

Velocities with Varget over 180 grain bullets were right at 2400 fps, with very little muzzle flash.

So we duplicated that load in the 308 Win case, which is in the low to mid range in most manuals.

This load 41.5 grains of Varget over CCI250 primers under the 180 grn Roundnose Speer bullets he had on hand gave him an average 2435 fps out of the 20 inch, finished length barrel we installed on that Mod 70 SA.

I wanted to profile the barrel of at least cut steps to lighten it but he loved the extra weight and it helped to hold the rifle steady. After all, he wasn't carrying it.

To be honest, I wasn't expecting that barrel to shoot as well as it did. But the fellow shooting it was getting moa groups out of that load almost from the first shots.

He was a happy man.

He wanted to move away from the lever action, which had been a gift from his deceased father, before he had the bike accident that confined him to a wheel chair.

He found it awkward to cycle the action while in his wheelchair.

It's close to what you're looking for but you may have to tune the load to your rifle.
 
I never shot weight greater than 168gr, but Varget performed best in several different 308’s…. one which had a 20” barrel. My understanding is that virtually all the powder is burned by the time the bullet has moved a few inches down the barrel. It is further my understanding that “muzzle flash” is typically not related to the ignition of unburned powder.

This is correct, and with only a rare exception, the powder that gives the highest Velocity in a long barrel
will also give the highest velocity in the shorter barrel. [there will be velocity loss in the short tube, naturally]
I have proved this to my own satisfaction with a 30-06 that started with a 26" barrel, and ended with a 19"
tube. Dave.
 
Muzzle flash is not unburned powder as one would think but rather super heated gases glowing when exposed to oxygen. If the pressures are what the powder was designed for it will burn completely in the first few inches of barrel.
 
This is correct, and with only a rare exception, the powder that gives the highest Velocity in a long barrel
will also give the highest velocity in the shorter barrel. [there will be velocity loss in the short tube, naturally]
I have proved this to my own satisfaction with a 30-06 that started with a 26" barrel, and ended with a 19"
tube. Dave.

Muzzle flash is not unburned powder as one would think but rather super heated gases glowing when exposed to oxygen. If the pressures are what the powder was designed for it will burn completely in the first few inches of barrel.

X2 to both with one subtle change: "If the pressures are what the powder was designed for, all that will burn will be consumed in the first few inches of barrel".

No matter the pressure, 100% burn cannot be expected. Further, beyond the gasses, there are solid by-products of burning (which vary slightly between powders), so soot, etc. is not "evidence" of an incomplete burn, just evidence that the gun was fired.
 
^^^ I would agree

I tried Varget, BL(c)2, and IMR 3031 for my 308 shooting 168 gr bullets

Varget was a sorry third place finisher. While I know others have good success with it, I have not
I think it is a bit over hyped, and (before the pandemic) was overpriced compared to the other powders available

BL(c)2 meters like a dream. Probably going to be my go to powder
 
i asked similiar question in 30-06, got a reply somehing alike, ' whatever load works now will work then ' or the 'best powder for then is the best powder for now '

Varget seems the G o. in everything haha.. Even old mates Garden
 
Muzzle flash and muzzle blast are caused by gasses - not by unburnt powder. Powders have additives to reduce this.

Some more than others.

Any of the medium speed powders will work well with your 20" barrel. 3031 to 4350 in speed. I like Varget, 4895, RL15 and 748.

For hunting (cold weather) I would start with Varget.
 
So with this - shot my shorter 30-06 today with the same loads from the developed 22 inch barrel loads--- 130-150gr shot poor but the 180s load worked ok for more testing.

my question is, when re developing this load, would it be more likely that the velocity is what made the longer barreled loads the accuracy- and is there connection to the shorter barrel wanting a hotter load to reach that velocity / accuracy pairup? oor is it unlikely an more a harmonics thing?

fyi the groups were not excessive although a bit random-
barrel does warm quicker i found with the flutes?
early stages of testing but continuing with Varget - yeah...? seems alright for 20 inch an most likely 150s
 
It is harmonics that determine accuracy. Load a string of incremental loads of 0.3 gr and the groups will show a clear winner.

true- interesting, i should do this next time round. i didnt see this and loaded 3x rounds for testing min to the previous load.... showing good sign of consistency .5gr below 130gr previous charge weight.
an early stages 150gr showing it might also be a gr down but too early to say...proberly should hold off on the 150s an do the above mentioned ladder- isnt it.. anywho

thanks gander
 
Looking for recommendations for the most appropriate powder for the following:

- Caliber is .308 Win.
- Rifle is a Tikka bolt action.
- Barrel length is 20in.
- Bullets will be 180gr Nosler Accubond.
- Would prefer it to burn completely within the barrel (not looking for a "flamethrower").
- Want to maximize the potential of the bullets, this is for a hunting load.

Thanks!

I have shot a 20" barreled 308 for years using 190 gr SMKs and Vit N550. Velocity of 2570 FPS ( I am right on the edge of over pressure however at this velocity so brass life is not great) and as close to zero flash as I have ever seen. The 550 is extremely clean burning.
 
Want a real crowd pleaser load, just get some 125-130 grain pills, and put a good load of H335 in it.
It’ll shock the beegeezers outta all present……….
 
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