308 load issues

[Tikka_taca1]

MY RIFLE:

16” tikka Tac a1
1/11 twist barrel
4-16 steiner optic

THE LOAD:

175 gr nosler rdf
41.0 imr 4064
Federal brass
Fed match primer
2.8 oal

I size the brass in a Redding fl bushing die and seat with a Forster micrometer die, I have the died in a lyman all American 8 press

at 100 I can put 5 rounds in a penny but at 600 the load completely falls apart (see photo) with factory 168 fgmm I can just about put them in the same hole, but at 600 they also fall apart and are inconsistent as well

no idea what to do about it other then sell the gun and try something else

 

[Doc68]

Is your paralax adjusted correctly?

 

[Sieg]

What's YOUR velocity at muzzle and 500yds?

Appears bullet stability may be an issue?

The shooter influence is also magnified 6x vs 100yds.

 

[918v]

Try a higher powder charge at a longer coal.

41.7 at 2.830”

Chrono it.

Review your case prep. How do u do it?

 

[918v]

What's YOUR velocity at muzzle and 500yds?

Appears bullet stability may be an issue?

The shooter influence is also magnified 6x vs 100yds.

It’s not a stability issue

 

[sea2summit]

What's YOUR velocity at muzzle and 500yds?

Appears bullet stability may be an issue?

The shooter influence is also magnified 6x vs 100yds.

This^

That 16” barrel with 41 grains of 4064 I bet your MV is down in the low 2350 fps range max.

 

[Tikka_taca1]

This^

That 16” barrel with 41 grains of 4064 I bet your MV is down in the low 2350 fps range max.

you are correct

 

[918v]

This^

That 16” barrel with 41 grains of 4064 I bet your MV is down in the low 2350 fps range max.

Wrong

This bullet has a SG of 1.42 at that velocity at sea level at 32deg F.

 

[Doc68]

It’s not a stability issue

This, if it was a stability issue you would be seeing keyholes or a oblong hole in your target. A 2350 MV isn't going to create a stability issue at 600.

 

[sea2summit]

you are correct

Maybe try some 4895 or something faster and see if you can get it up a little faster? Might do better.

 

[Doc68]

Have you checked your scope Paralax?

 

[Tikka_taca1]

Have you checked your scope Paralax?

i did it seemed ok but that could maybe be some of it ??‍

 

[sea2summit]

Wrong

This bullet has a SG of 1.42 at that velocity at sea level at 32deg F.

Well if he’s shooting at 32 F he might want a 1/10.5 or better.

ETA or is it slower twist with the cold. Damnit don’t make me try to remember math when I’m three beers in.

 

[supercorndogs]

The hand load and the 168 FGMM both fall apart at 600, I don't think the ammo is the problem.

 

[Tikka_taca1]

More info

 

[Tikka_taca1]

More info

 

[supercorndogs]

Are the shots all over the backer yours too, or just whats on the target? Is that a 10 inch target?

 

[Tikka_taca1]

Are the shots all over the backer yours too, or just whats on the target? Is that a 10 inch target?

all mine and 12”

 

[wade2big]

Its more than likely the shooter my friend. Parallax issues are not the problem either. Never is.

 

[Tikka_taca1]

Its more than likely the shooter my friend. Parallax issues are not the problem either. Never is.

could be

 

[wade2big]

could be

Is that a 5 shot group in your last picture? I just realized that I am in the reloading section. Cant help with that except to say it probably isn't the issue. Put more lead down range and it will Tighten up.

 

[Tikka_taca1]

Is that a 5 shot group in your last picture?

yes federal 168 fgmm

 

[padom]

Just because you shoot tiny groups at 100 doesnt mean that will translate at distance. I see this all the time when people pick there smallest groups for their load and arent in a node.

How did you do load development? What's your ES/SD? A lot of vertical on that target.

 

[Tikka_taca1]

Just because you shoot tiny groups at 100 doesnt mean that will translate at distance. I see this all the time when people pick there smallest groups for their load and arent in a node.

How did you do load development? What's your ES/SD? A lot of vertical on that target.

20 or less

 

[padom]

20 or less

How did you do load development and select that load?

 

[padom]

20 or less

20 What? ES or SD?

 

[supercorndogs]

yes federal 168 fgmm

The 5 on the 12" target are the 168 FGM and the ones on the backer came from shooting groups with the other load?

 

[wade2big]

20 What? ES or SD?

Even a SD of 20fps would only account for 4” of vertical spread at most at 600 yards.

 

[padom]

Even a SD of 20fps would only account for 4” of vertical spread at most at 600 yards.

Not being in a node can make a target look like buckshot as you walk it out to distance

 

[padom]

I also wouldnt trust an RDF to save me life. Nothing but issues with them in multiple calibers. 175smk would be what I'd be testing with Varget or H4895 in that short barrel.

 

[wade2big]

Not being in a node can make a target look like buckshot as you walk it out to distance

You would know more about that than me.

I was just using the logic of tight groups at 100 yards along with worse case the OP meant an SD of 20. I thought not being in a node meant higher SD. High SD dont mean a whole lot a 600 yards. Practically speaking that is. I guess it does if you are looking to shoot ittty bitty groups or small targets.

 

[padom]

You would know more about that than me.

I was just using the logic of tight groups at 100 yards along with worse case the OP meant an SD of 20. I thought not being in a node meant higher SD which. High SD dont mean a whole lot a 600 yards.

Not necessarily. Not being in a node means the barrel is not releasing the bullet at the same point in its whip each time.. your barrel makes a whip or circle motion when fired. The point of doing load development to get in the center of a node is finding the point where your bullet is released at the same point in that whip every time.

 

[HiDesertELR]

Not being in a node can make a target look like buckshot as you walk it out to distance

This x100.

 

[wade2big]

Not necessarily. Not being in a node means the barrel is not releasing the bullet at the same point in its whip each time.. your barrel makes a whip or circle when fired. The point of doing load development to get in the center of a node is finding the point where your bullet is released at the same point in that whip every time...

And that wouldnt necessarily cause a larger dispersion at 100 yards than what the OP is showing?

 

[padom]

And that wouldnt cause a larger dispersion at 100 yards than what the OP is showing?

Nope. I've seen one hole groups not in a node. Read up on Dan Newberry OCW. This is why we ignore group size when doing load development at 100yd.. but I see the mistake made all the time where guys choose the tiny group.

What you should be looking for is multiple charges with the same POI. This is your node. This is your confirmation bullet is being released at the same point in the whip for these charges...you now select the middle of those.charges.... consistent point of impact is king...once you have done that, you go do a seating depth test to shrink group size..

 

[padom]

This is why I asked the OP what load development he did and how he chose this load... now if the charges above and below this had the same POI then I would look elsewhere to shooter or equipment, etc.

 

[Doom]

You are not on the node that approximates FGMM. As 918v says you should find that around 41.7 to 42 Grs. The RDF should be happy in that load range.

 

[padom]

You are not on the node that approximates FGMM. As 918v says you should find that around 41.7 to 42 Grs. The RDF should be happy in that load range.

You are correct that is the known node for FGMM but remember he has a 16" barrel. FGMM did not shoot well for me or the 4064/175smk load in my 16" 308 but was a tack driver in my 24"...

175smk hammered in my 16" with Varget and H4895. 100% consistent on 8" round plate at 800yd.. hit percentage dropped to 50% @ 1000 because of velocity.

 

[wade2big]

You are correct that is the known node for FGMM but remember he has a 16" barrel. FGMM did not shoot well for me or the 4064/175smk load in my 16" 308 but was a tack driver in my 24"...

175smk hammered in my 16" with Varget and H4895. 100% consistent on 8" round plate at 800yd.. hit percentage dropped to 50% @ 1000 because of velocity.

Your hit percentage Probably dropped because of the wind. Lol. A little puff and that bullet is gone at 1000

 

[padom]

Your hit percentage Probably dropped because of the wind. Lol. A little puff and that bullet is gone at 1000

Nope velocity... was just going transonic at 950...

A supersonic bullet goes transonic when drag causes it to lose enough momentum to drop below the speed of sound. The aerodynamic effects on the bullet change dramatically as it goes through the transonic range, destabilizing the flight of the bullet and making it erratic

 

[Tikka_taca1]

I font have the old targets, but what I did was knowing 175 fgmm was 41.0 of 4064 I worked 40,40.5,41,41.5,42 I did 3 round groups picked the best of them which was 41 and 41.5 shot them both in a 5 round string and if I remember they where both pretty much the same 42.0 was junk

 

[padom]

I font have the old targets, but what I did was knowing 175 fgmm was 41.0 of 4064 I worked 40,40.5,41,41.5,42 I did 3 round groups picked the best of them which was 41 and 41.5 shot them both in a 5 round string and if I remember they where both pretty much the same 42.0 was junk

What does picked the best mean?

 

[Tikka_taca1]

What does picked the best mean?

Means I picked the ones that where the tightest groups, when I bought the Redding bushing die and a .003 neck bushing (last spring) that die brought my es/sd down tremendously, my new brass gets trimmed and neck sized with a lee neck sizing die

 

[padom]

Means I picked the ones that where the tightest groups, when I bought the Redding bushing die and a .003 neck bushing (last spring) that die brought my es/sd down tremendously, my new brass gets trimmed and neck sized with a lee neck sizing die

There lies your problem. Picking tightest groups is not how you do load development and select a load. It's a big mistake a lot of people make. Group size should be ignored when selecting your load. This plays true whether you are using the OCW or ladder method. You're looking for consistent points of impact, not group size. You can shrink groups in the last stage of development by doing a seating depth test AFTER selecting a load in the center of a node.

Dan Newberry's OCW Load Development System

Dan Newberry OCW or Optimal Charge Weight Load Development method or system for handloading, reloading, bullets, brass, powder, primers, accurate handloads.

optimalchargeweight.embarqspace.com

 

[Doom]

You might also want to look at using the 168 or 175 SMK, or similar as opposed to the newer high BC bullets. They should be easier to get a good load with, particularly if your chamber has a long throat or leade.

 

[diving dave]

Just to dogpile on, shoot a ladder test at 300. Dont worry about left /right impacts, what your looking for is vertical placement. Start with the load that has the least amount of difference.

 

[Tikka_taca1]

Here are some updates I loaded from 40.0 to 41.6 in .2 increments, I can go higher if needed

 

[918v]

Go higher and increase the coal

 

[Tikka_taca1]

Go higher and increase the coal

increase by how much ? .001 .01 .02 ?

 

[918v]

increase by how much ? .001 .01 .02 ?

.030” or so. How long of a round can you fit in your mag?