Powder and Primers - .308Win F-Class

[Papa Charlie]

I have been shooting .308 Win in my F-TR rifle, I am thinking about is there a better powder or primer that I should be using.

Rifle:
Remington 700 Trued and Blueprinted action
Barrel: 1:10 Twist
30" Heavy

Rounds:
Berger 185gr Juggernauts
Lapua Win brass
CCI BR-2 primers
Hodgdon Varget

I am get an occasional flyer and wonder if it could be either the powder or primer. Use an analytical scale so I am sure that the loads are consistent. I am going to try some Federal 210M primers to see if they perform any better. But was wondering if maybe some Hodgdon H4350 might be a good alternate choice.

Are there any other primers or powders that I might try?
What do you think about the H4350?

Thanks very much for the input.
Patrick

 

[Terry]

The occasional flier is usually me, or the tune. Sometimes backing off on the powder charge fixes it.

 

[Papa Charlie]

The occasional flier is usually me, or the tune. Sometimes backing off on the powder charge fixes it.

Couldn't agree more. Hard sometimes to distinguish between the two. I just went through a lengthy load development and I am confident of the load. But wonder if a different primer may provide more consistent results. So next match I will be using the Federal 210M's.

Still haven't decided whether to use the Federals for all three relays or just one of the relays.

 

[LVLAaron]

You wont have enough room in the case for H4350. If you're determined to try something new, I'd go with N140. Some folks use H4895 but by and large, Varget is the powder of choice.

 

[Papa Charlie]

You wont have enough room in the case for H4350. If you're determined to try something new, I'd go with N140. Some folks use H4895 but by and large, Varget is the powder of choice.

That was a concern. I am using 45.7 gr of Varget now. There is only 0.460" of clearance between the top of the powder and the top of the neck. Seating at 0.010" OTL's means that there is only about 0.039" of head space.

 

[J F Johannes]

45.7 gn? Yikes! Muzzle velocity? LRP brass? Check your crown.

Jim

 

[Papa Charlie]

Sorry fat fingered that one, 42.7 gr (gn), Muzzle Velocity is 2669 fps avg.

No issues with brass. I have some brass that have been fired 24 times. I do anneal every firing.

I have load test up to 45.5 gr (gn), 2817 fps avg, with no issues though.

 

[J F Johannes]

You were at 2750fps +/- last year and your rig was hammering, why don't you go back to that velocity? 44.2 - 44.4 should get you there. Also go back to original seating depth(last year) and try that. IMO barrels get slower as they age, add powder. I don't believe in chasing lands, hasn't worked for me.

Jim

 

[Ned Ludd]

In a 30" barrel with an appropriate freebore (~.120" - .170"), there is a very good accuracy node with Varget and 185 Juggernauts at somewhere in the neighborhood of 2725 to 2750 fps. Although the Juggernaut is a tangent ogive bullet and relatively tolerant of seating depth, I have occasionally had a Lot# of Jugs that seemed very finicky for some reason. I test in .003" seating depth increments, and the Jugs usually seem to tune in somewhere between ~.015" and .021" off the lands. As mentioned above, H4350 is too slow and bulky to be the best choice in a .308 Win case with 185s.

Just out of curiosity - do you point your 185s? If so, in terms of pointing, a little goes a long way. Over-pointing might be the cause of an occasional flyer. If you are not pointing bullets, it might be worth a look. I have found that in addition to a small increase in BC (perhaps 4-5% with the Jugs), proper pointing of bullets can also improve the consistency of groups.

Testing different primers can certainly be a worthwhile exercise. However, if your load already has good ES/SD values, I'm not sure that switching primers will have any effect on the occasional flyer. You will just have to test and find out. I have had very good results using Fed primers (205s or 210s) with Varget in .308 loads. Just remember that when you switch to a primer with different brisance, it is not uncommon to observe a noticeably different velocity for a given charge weight. Basically, you're altering powder ignition, which can cause much different acceleration, and ultimately, muzzle velocity, even with the exact same charge weight. To properly evaluate the primer being tested, the load will need to be re-optimized. So changing primers can sometimes be like starting load development all over again.

 

[LVLAaron]

You were at 2750fps +/- last year and your rig was hammering, why don't you go back to that velocity? 44.2 - 44.4 should get you there. Also go back to original seating depth(last year) and try that. IMO barrels get slower as they age, add powder. I don't believe in chasing lands, hasn't worked for me.

Jim

That's exactly where I run them. 2725-2750 - 44.2 varget

 

[Papa Charlie]

Last year I was at 2737 fps with 42.9 gr of Varget and yes I was getting very good results. Fast forward to March of this year and it all seemed to fall apart.
The only thing I changed was to go from seating with my Redding Comp die to a LE Wilson inline and a K&M Arbor press.

I have recently started load development and only when I went back to the Redding seating die did the grouping start to tighten up. Also in testing from 41.0 to 45.5 gr at 0.015" jump, 42.5 to 43.0 started to show the node. I retested 42.5, 42.7 and 42.9 with adjusting seating depth from 0.005 to 0.025 in 0.005 increments for each powder load. The winner seems to be 42.7 at 0.010 jump. All testing done at 220 yards with perfect days with no wind.

It was obvious as the velocity approached 2700 all the way past 2800 fps the grouping just fell apart. Why I don't know. The barrel has 1700 rounds down the pipe. Might have something to do with it.

The new velocity at 42.7 gr, 0.010 OTL is 2685 fps average, SD 7.8 and ES 22.0, over the 5 rounds fired during development.

My first real test will be next weekend in a 500 yard match. One thing I plan to do differently is to load with Federal 210M primers. My original thought was to load only one relay with the 210Ms but one relay could be good or bad on a fluke so changed plan to shot all three loaded identical. I am concerned that I may be altering my new load and thereby it's outcome. But this is a great opportunity to test at distance.

I do not point my rounds. Have considered it but don't want to add anything new until I get things under control. Otherwise I won't know what is causing what as I get back to where I was.

 

[mike06]

When Varget was hard to get the go to powder and my range was IMR 4320 I have found ArComp to be my favorite with 168 or 175.

 

[J F Johannes]

Pat, just for sh@ts and giggles load up 22 rounds at your condition 3 44.0 gn (2750 +/-) you posted earlier in “load development at 100” and shoot it in practice after the Saturday match and see how it prints at 500. I have some srp brass I want to test if it gets here in time. I feel your pain as my barrel is getting near its end.

Jim

 

[Papa Charlie]

Jim I appreciate it, but I spent the last Match doing just that along with another relay in practice. That is what drove me to do the load development.
At this point I need to play the hand out and see where I end up.

 

[J F Johannes]

Okay, I will see on Saturday.

Jim

 

[Liven The Dream]

I run that same set up in a 30" Brux 1-10.
Peterson SRP Brass CCI 450 . 44.0 grs. Varget .010 in.
Flat Hammers , if I am on my game.

I had a Barrel before this one that Varget and it never got along.
Tried 4320 and shot dots ????

I see R-15 on write ups at times ?

Flyers ? My shoulder can do them ….

 

[dttheliman]

I run that same set up in a 30" Brux 1-10.
Peterson SRP Brass CCI 450 . 44.0 grs. Varget .010 in.
Flat Hammers , if I am on my game.

I had a Barrel before this one that Varget and it never got along.
Tried 4320 and shot dots ????

I see R-15 on write ups at times ?

Flyers ? My shoulder can do them ….

Yep I have one of them - absolutely hates Varget from 155's through 185's - Try 4320 / R15 or AR Comp

 

[Ned Ludd]

Papa Charlie - have you borescoped that barrel recently? Loads don't typically just fall apart like that, especially with a bullet as easy to tune and forgiving as the Juggernaut. From your description, it is possible you could have some kind of issue not directly related to the previous load you were using. If so, any load development at this time will be a wasted effort.

 

[Papa Charlie]

I current do not. I sold the one I had recently, but had examined the bore closely after this issue started and could see nothing.

I have seen my grouping come back inline with this load development at least at 220 yards. I will see if it performs at 500 yards this weekend.

What was strange is that when I put the rifle away after our last match in August last year, it was shooting well. In November I purchased the Wilson Seating Die and K&M Arbor and it wasn't until March when we had our first match that I saw that everything had fallen apart.

I do need to order a Bore Scope from Amazon. I want one that I can plug into my computer or use as blue tooth but don't know which one to purchase. Any suggestions?

 

[Nature Boy]

I was running 185 Hybrids with 43.5g of H4895, 210M primers at .030 off, 2,720fps and that load shot consistent high master scores at 600 yards. Changed powder lots and started to see some pressure signs. Did another Cortina OCW and found the node 0.5g lower at 2,747fps, SD 5, ES 17.

So I guess I'm echoing what others are finding with the 185g Bergers; there's an accuracy node in that 2,700 - 2,750 range