Looking for perfect 308 bullet and barrel combo

M

MartyK2500

CGN Ultra frequent flyer
Rating - 100%
278   0   0
Location
Quebec
Right now going through a sizeable downsize in my shooting stuff, fifth wheel was just signed for, I'll travel with the family instead of hogging all my personal time at the range.
I do want to keep an LR rifle and I'd like it to shoot 1/3-1/2 moa consistently.

Will be using a Manners PRS stock, NF ATACR, Origin action, and feed everything from the mag.
I wish for this rifle to be my main LR precision rifle, and do it all even though not perfect for all.
Petawawa 600M service rifle, Connaught 900M, private land 700M, local range 200M bench for tightest groups possible

For barrel profile, I'm looking at a 26'' with 0.920'' at muzzle, 3/4x24 threads with insite brake, 308, 1:10, 5R
For bullet I'd like to try 185 Juggernauts
Brass Lapua large primer with BR2, would consider going SR magnum primer if I can hide pressure better to get that 900M velocity
Powder Varget


In my given situation, would you change anything in barrel specs or bullet choice?
What would be a solid choice to shoot a 308 out to 900M?

In my past experiences, my 308s with 175s would perform solid out to 800M and start fussing around at 900M, hence why I had got into 6.5x47
If 308 turns out to perform poorly in a shorter 26'' (vs 30'' FTR) I'd probably stick with 6.5, but this would block my from Petawawa caliber restrictions.
 
Last edited:
If you want to keep it simple in F Class F-TR and have a combo that is easy to load and works well in a 1-10 twist barrel try this:

185 Berger Juggernauts seated 5 thou off the lands.
43.0 Gr Varget (+/- 1 grain)
I use Prepped Federal GMM large primer brass and a Fed 210 large rifle Match primer.


I use this load in a 26" barreled PGW Coyote and it shoots fantastic out to 900m. This combo gives me a SD of between 6 and 9 FPS most days.

Lapua brass and CCI Br2's will work as well or better. You won't need a magnum rifle primer. If shooting F-TR at Connaught you don't need them loaded to fit in the mag, seat them long and single feed them.


As far as your rifle specs go, ditch the brake. The gun as spec'd should be heavy enough for you to soak up the recoil and the brake is not going to help accuracy.
 
prairieguy said:
If you want to keep it simple in F Class F-TR and have a combo that is easy to load and works well in a 1-10 twist barrel try this:

185 Berger Juggernauts seated 5 thou off the lands.
43.0 Gr Varget (+/- 1 grain)
I use Prepped Federal GMM large primer brass and a Fed 210 large rifle Match primer.


I use this load in a 26" barreled PGW Coyote and it shoots fantastic out to 900m. This combo gives me a SD of between 6 and 9 FPS most days.

Lapua brass and CCI Br2's will work as well or better. You won't need a magnum rifle primer. If shooting F-TR at Connaught you don't need them loaded to fit in the mag, seat them long and single feed them.


As far as your rifle specs go, ditch the brake. The gun as spec'd should be heavy enough for you to soak up the recoil and the brake is not going to help accuracy.
Click to expand...

Hi, thanks for the info.
Btw I am not shooting Fclass, with the service rifle section we used to have 900M every monday evening before covid.
This rifle will always be shot from the magazine.

Funny how 43gn of Varget is a universal powder load to so many bullet combos, it was my GOTO load for 175 SMK in my service rifle bolter, and for Berger 208 LRHT in my FTR build I had.
 
kthomas said:
Scratch all that and buy a Tactical Operations X-Ray 51.
Click to expand...

I had never heard of them before.
Looks cool I love old school builds that shoot lights out.

I'll work with what I got, just need a barrel and a few hundred bullets to start off with.
Rest of the money going into a Blackstone griddle, Honda 3000eu generator, RV renovations (like solar power and better stairs).
 
With the .920 muzzle size you won't need a brake. I find that while great at stopping recoil they seem to open up my groups.
1-10 twist will do anything you want it to do.
I load 168gr for upto 300yds. Then 175's for after.
My rifle loves the Speer 168gr bullets. Which is odd given the reviews and price. But the 175 TMK are very good for the longer distances. I've only really shot out to 750-800. As I haven't been able to go find a new spot due to all the fires as of late.
Lapua brass is probably the best. But don't overlook the Starline SRP. The ones I have got have been very consistent. Just Lapua seems to last longer.
I have a soft spot for the 308.

I have both a JC (Sendero) and a IBI barrel (heavy .920) Both 26"
JC likes 4064 or 4895.
IBI loves ball powder. BLC2, CFE223 and 748.
Neither like Varget.

Sounds like a great build. Look forward to the pictures.
 
Actually... if ever I do go brakeless, I could technically go out and shoot with the Fclass guys using my single shot AICS sled.
Not competitively, but at least another option to spend some range time.

Edit : brake it is, on private land we often shoot from the tripod and sometimes try out positional shooting. With my current braked 308 it does recoil in these positions, I won’t give myself a harder time than required.
 
Last edited:
kthomas said:
Scratch all that and buy a Tactical Operations X-Ray 51.
Click to expand...

MartyK2500 said:
I had never heard of them before.
Looks cool I love old school builds that shoot lights out.

I'll work with what I got, just need a barrel and a few hundred bullets to start off with.
Rest of the money going into a Blackstone griddle, Honda 3000eu generator, RV renovations (like solar power and better stairs).
Click to expand...

This ?

https://www.snipercentral.com/tactical-operations-xray-51/
 
If it were me, I'd just have 2 barrels (ie .308 and 6.5) and swap them around depending on what I was gonna be doing. You just won't get the performance that you want at 900m from a mag-fed .308. If you're dead-set on only having the one barrel in .308 then I'd say try out the higher BC offerings in 175-185gr (175 RDFs, 175 TMKs, 178 ELDMs, 185 Juggernauts) as they all have a way better BC than the old SMKs.
 
Kthomas…
If your only shooting 185 it won’t be any less versalite and the accuracy potential may go up.
But if you want to shoot heavier down the road, then by all means a 10t is the way to go.
The thread title is “ Looking for perfect 308 bullet and barrel combo” not looking for the most versatile barrel!
Dave makes a good point!
 
10 twist, M852 reamer, 26" finished, add a BIG brake

Sierra 195gr TMK from the mag (2.9+")... can also do very well at 1k on an F class target.

Sierra 200gr MK or Berger 200-20X single fed if shooting F class.. or if you want to plink out towards 1 mile.

simple...

Jerry
 
joehunt said:
Kthomas…
If your only shooting 185 it won’t be any less versalite and the accuracy potential may go up.
But if you want to shoot heavier down the road, then by all means a 10t is the way to go.
The thread title is “ Looking for perfect 308 bullet and barrel combo” not looking for the most versatile barrel!
Dave makes a good point!
Click to expand...

Bryan Litz tested 175gr SMK and Berger OTM in a 1-8", 1-10" and 1-12" 308win. The Sierra group sizes decreased with increasing twist, but the Berger didn't. The effect of twist rate on precision depends on the bullet being used. A faster twist will increase group size for unbalanced bullets with poor runout. A quality bullet like a Berger, with a uniform jacket thickness, consistent weight distribution, centre of gravity, and low runout, is going to be statistically unaffected by a faster twist.

If you are shooting at 100yards Benchrest, then yes, a slower twist to reduce dispersion caused by bullet imbalances is the way to go. But since at short ranges, this dispersion due to imbalance is the primary factor of mechanical group size. At longer ranges, like what the OP will be shooting at, the BC of the bullet has a greater impact due to retained velocity, wind drift etc. And having a tighter twist means you can shoot heavier, higher BC bullets with higher effective BC.
 
Thanks all for the feedback!

Jerry, I had a screaming deal for many boxes of berger 185s from a local.
How will the M852 reamer react to 185s?
I’d want at least 2/3s of the neck engaged on the bullets bearing surface.
I will buy the barrel from you by the way :cheers:

Btw I am not firm on the Berger 185s I could always flip them.
 
Last edited:
Alpheus said:
Bryan Litz tested 175gr SMK and Berger OTM in a 1-8", 1-10" and 1-12" 308win. The Sierra group sizes decreased with increasing twist, but the Berger didn't. The effect of twist rate on precision depends on the bullet being used. A faster twist will increase group size for unbalanced bullets with poor runout. A quality bullet like a Berger, with a uniform jacket thickness, consistent weight distribution, centre of gravity, and low runout, is going to be statistically unaffected by a faster twist.

If you are shooting at 100yards Benchrest, then yes, a slower twist to reduce dispersion caused by bullet imbalances is the way to go. But since at short ranges, this dispersion due to imbalance is the primary factor of mechanical group size. At longer ranges, like what the OP will be shooting at, the BC of the bullet has a greater impact due to retained velocity, wind drift etc. And having a tighter twist means you can shoot heavier, higher BC bullets with higher effective BC.
Click to expand...


Once a given bullet achieves full stability. There is no advantage in going to a faster twist.
And possibly a disadvantage.
Some bullets are better then others, but all bullets will have some tolerance.
 
Last edited:
joehunt said:
Once a given bullet achieves full stability. There is no advantage in going to a faster twist.
And possibly a disadvantage.
Some bullets are better then others, but all bullets will have some tolerance.
Click to expand...

No disadvantage to going faster unless you overspin the projectile to the point it deforms.

A 1:10 twist is perfectly fine, and is one of the better twist options for .308.
 
All I can say from experience,
My current iBi has often achieved 1/3 moa 5 shot groups at 200M with 1:10 twist and light 175SMKs.

Times I shot at 800M with electronic target it would keep within 5/8-3/4 moa if the wind didn’t play tricks.
At 900M it would shiit the bed and groups opened up big time
 
kthomas said:
No disadvantage to going faster unless you overspin the projectile to the point it deforms.

A 1:10 twist is perfectly fine, and is one of the better twist options for .308.
Click to expand...

I agree that a 10t is fine for a multi purpose 308. But if your looking for the “perfect 308 bullet barrel combo” and you have chosen the 185 juggernauts….
I propose that all other things being equal, an 11 or 11.25t will out shoot a 10 with 185s.
How much is hard to say.
 
Last edited:
MartyK2500 said:
Thanks all for the feedback!

Jerry, I had a screaming deal for many boxes of berger 185s from a local.
How will the M852 reamer react to 185s?
I’d want at least 2/3s of the neck engaged on the bullets bearing surface.
I will buy the barrel from you by the way :cheers:

Btw I am not firm on the Berger 185s I could always flip them.
Click to expand...

The 185s should work just fine in the M852 chamber... or a reg 308 Win SAAMI chamber.

Send me an email when ready Thanks

Jerry
 
You must log in or register to reply here.
Back
Top Bottom