Need comments regarding load test results, group size, fps, etc. 308

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Kryogen

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Did some testing today in a 26 inch 700P. All rounds are 2.800

1- shot 2 groups of a load that works fine for me, 43.0 H4895 with HDY match BTHP (near max load in my rifle though, I got extractor marks on some brass. Around 2800 FPS)
Fireformed brass that had been FL bumped.
Those were the best groups. 10 shot each

Then, I am also working up a load for my new 175 TMKs with lapua brass. (first firing). Those were ran through a lee collet die prior to loading to open up the necks evenly.
5 shot groups

Strange thing, from 42.0 to 42.5, velocity went same, lower, lower, back to intial velocity, and then higher. uh?

ES went 25, 25,35,16,11,37

Load with the lowest ES (11) was the worst group (42.4), horizontal and vertical spread.
Load with ES of 16 was the best. (42.3)

There is only .1 grains diff between the best and worst group.

Still not near a max load in this rifle (no pressure signs).
My plan is to keep loading until I get pressure signs, and then figure out below that what was the best load.
Maybe I am getting near a better load as I load a bit hotter?

See results: Quite disappointing groups
Any why is my crimped load 40 fps slower than my not crimped load? (cant be sure that I have used the same brand of primers, can primer brand seriously change fps by 40? (all large rifle)) Maybe some Win, S&B

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Make an OAL length gauge or use some of the commercial offerings.

With SMK's and TMK's .010" to .020" jump to the lands is a good starting point.
 
Ganderite said:
Is the rifle properly bedded? if not, you are wasting bullets.
If it is, I would load hotter until you reach max. In 308, the hot loads are often the best.
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It's in an AICS chassis (but I did not bed the rear part), I can cloverleaf with the hornady match BTHP 168s, and those 175 tmk fly all over the place. Weird. That 42.4 group is really bad, and really shot lower also, weird.

See group 16, was shot with my 168 and H4895 load, while it's not perfect, it's at least a decent 10 shot group.... (and it's a near max load)

Ok, I will load hotter and report next time I go. Probably will be next friday, that's when I'll have time to shoot.

I wont start playing with the OAL until I have completed the load ladder though.

The 700P has a really long leade and to be 10 off the lands I need to seat with only .150 or so in the case. I'll try to find a load that works the best with stock OAL, then play with OAL, maybe.
 
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Myself I use Lapua brass in both 308 and 30-06.

I have never ran the brand new brass through any collet die.

Never had an issue with the 308 at out to 1150 yards on targets, or working up NBT/Accubond hand loads in the 30-06 deer rifle.
Your powder loading methods appear to not be circumspect, I think so myself.

I strongly suspect, that if you buy Lapua new brass & right away, seat primers/throw powder/seat bullets, this "issue" will mysteriously disappear.

my 2 bits only

let us know how it works out.......:)
 
AICS torque spec is 53 in/lbs.

When you get all your brass fire formed, neck size only for as long as you can.

The 175/Varget/Wolf LR Primer or CCI BR2 Primer is a tried and true combination that you see very often in FTR matches.
 
See results: Quite disappointing groups
Any why is my crimped load 40 fps slower than my not crimped load? (cant be sure that I have used the same brand of primers can primer brand seriously change fps by 40? (all large rifle)
Click to expand...

Yes. Primers make a difference. Choose one, don't mix them.

Wolf LR and CCI BR2 primers are very popular in F Class.
 
I do think you need to adjust your C.O.L., I have never loaded less than 2.850 and my newest rifle, loaded with 175 TMK's is 2.930. Use a comparator is what I would suggest. I haven't always found hot loads the best, in my loads I tend to mid range+ loads. I have always had good luck with Varget, but also 4064 and BLC-2 seem fine, all with BR2 primers. If I can't do 1/2 MOA at 100 meters, I've had a bad day and it's usually my fault, not the rifle.
 
H4895 looks promising - Repeat the test and see what your results are. Try shooting at 200 or 300yds also for load testing.

DITCH THE CRIMP!

Myself, I do a ladder to start x 2 at long range (400yds) then if the 2 ladders give the same info, then load up a few and shoot groups with the ladder info. Then once a load is found, then tweak the seat depth - fyi i have found 175 TMK and SMK all shoot best at 2.1" BTO using a sinclair ogive tool (that puts them right close to book COAL length), thats thru a Savage 12, Sig 3000, and a custom with Krieger. However, any bullets i use outside of MatchKings require tweaking depths for me.

Three rifles i have in 308 all like 41.7 to 42 gr 4064/Lapua/CCI BR primers. Varget was ok too, but not as good as 4064. You may want to try under 42 gr 4064 too. Accuracy trumps velocity.

Anyhow, my point is to repeat the test (and maybe do a ladder x 2) before you start tweaking things so that you know you are in the right spot.
 
Do you have a mag and feed ramp setup that allows you to shoot longer bullets? I use Accurate Mags without binder plates and I can load up to 2.970" COAL. I now load all my rounds using the same principle, I sit a round on top of a formed case, only the boat tail is in the neck, and measure the length. I subtract .300" and make that my COAL, meaning all my rounds are seated .300" in the neck. For example Berger 175, Sierra 175 and Berger 185 are all loaded at 2.900" COAL. Hornady 178 AMAX are 2.875". The result of that is the same volume inside the case for any bullet I load. I can also load more powder in the case. I'm pushing 175's at 2800 fps from a 24" barrel, 185's at 2700 fps. No pressure signs whatsoever. Best accuracy for 175's around 46 gr of IMR 4064, slightly compressed load.
 
700P with 175 TMK
Stock OAL is 2.800
Mag feed limit with some slack is around 2.880
I do hand feed all rounds, but why not develop a load that works at mag length IF possible.

OAL to lands is 3.042
Ogive is 2.331

Um, so thats a 242 mils jump to lands at standard oal.

With .308 in the case, that gives me around 2.875 with the 175 TMK
That should also feed well in my mag, and be properly supported with at least a caliber in the case neck.
I could try a 2.875 OAL, and that would also reduce the jump to lands by 75 mils, to 167 mils

That is an abusive leade in the 700P, I could fit the 175TMK+ my finger in there and I would still have room for a friend or 2.... and it's a 12 twist.

I have 1000 WLR primers and 1000 S&B primers, so I'll keep using the same batch for load dev and not switch brands. When I am done with those 2000 then I'll buy the BR2.
I have 8 pounds of 4064 so I'm not going with another powder for the next 1250 rounds or so.
Let's work around the components that I have.

Would you guys try to load longer than 2.875 or just keep it to 308 in the neck for load dev?
 
chrismc said:
DITCH THE CRIMP!
Click to expand...
It was only a test for fun, I am not crimping target loads.

chrismc said:
I have found 175 TMK and SMK all shoot best at 2.1" BTO
Click to expand...
That's 2.815 OAL, still pretty short in my rifle, would make no diff vs stock in my rifle (I have a 242 mils jump to lands with std OAL...)

chrismc said:
You may want to try under 42 gr 4064 too. Accuracy trumps velocity.
Click to expand...
I have started at 41.0 it wasn't much better. 41.9 wasn't too bad but still not where I want it.
 
I've been reading about people loading shorter than caliber into the neck. There's even sizing dies that allow you to adjust how much neck depth you actually resize. I haven't experimented with that and don't plan to for the moment. I think you could get away with it with a very small bullet runout. Where's your runout at? could explain some bad groups and flyers.

I have a Remington barrel and action with about .25" throat as well. Even at 2.950 I'm still about .100" from the lands. A lot of precision shooters load right into the lands, which is impossible for me or most people with factory rifles. Reading the Berger "VLD – Making It Shoot" article they recommend trying .010", .040", .080" and .120" from the lands to see what shoots best. Closest I can load is .100" off the lands, so that's what I do.
 
C23 said:
AICS torque spec is 53 in/lbs.
When you get all your brass fire formed, neck size only for as long as you can.
The 175/Varget/Wolf LR Primer or CCI BR2 Primer is a tried and true combination that you see very often in FTR matches.
Click to expand...

It was torqued to specs 500 rounds or so ago. Maybe I should re-torque it just to make sure?
Edit: i just checked and it was still torqued to specs.
My issue with neck size is that after a few firings they get hard to close the bolt on, then you need to FL, and then you don't have the same load and POI until you shoot the FL cases again to re-fireform and then go back to neck size...
I would rather use my forster custom neck FL die on a co-ax to just bump 2 mils all the time and keep it the same always.
 
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Also, I recently observed my rifle actually has two accuracy nodes. For example with 185's, the first node is around 42 gr of IMR 4064, .2-.3 MOA at about 2580 to 2600 fps. Pushing past that opens up the groups from 43 to 44 grains. Then at 45 grains the groups come back together, about .3-.4 MOA at 2700 FPS. For groups on paper at 100 meters the lower node would be best. I'm pushing the second node because I want to take the load to 1000 meters. Maybe in the end I'll stick with the lower node. I've observed this with 175's and 185's, no matter the brand of bullet.
 
Mmm ok I will load in .3 increments until I find another accuracy node near max (1000m load) then play with .1 to find the center of the node.

And i could do it all at 2.875 ....
 
Kryogen said:
Mmm ok I will load in .3 increments until I find another accuracy node near max (1000m load) then play with .1 to find the center of the node.

And i could do it all at 2.875 ....
Click to expand...

With my latest load developments I've been starting at published minimum and doing 3 round groups at .5 grains in between. That's 16 steps of .5 grains each. I stop whenever I get a hard bold lift for all 3 rounds in the step. I also inspect primers on every fired round at around or above published max. I don't tolerate any signs of over-pressure. I usually find the lower and upper node like that. I then pick whichever node I want to work on and load 50 rounds at .2 grains intervals, groups of 5. I honestly think I've been wasting 50 rounds developing my loads as playing around in .2 grains steps only marginally improved groups, sometimes not at all. IMR4064 being temperature sensitive, the .2 grains step that gave the best performance in the summer won't be the same in the winter. Next load I work on I'm going to stick to .5 grains steps, then fire the next 50 rounds at the best node and see if I need to tweak it.
 
YEs, my findings were that magical velocity in all of my 308's with 175 smk or tmk is 2600fps +/- 25 fps, at 2.81 - 2.82. I did try chasing the lands in a 5R (prob the same as your 700p) and even it shot best at 2.81 COAL.
Verify brass prep and the min FL sizing with 2 thou bump should get you there sooner or later once you find the cocktail.... Also, In my experience, which is limited, some rifles just won't shoot bugholes with certain components regardless of your efforts... sucks, but thats reality! My Sig won't shoot less than MOA with Varget, yet with 4064 it is 1/2 MOA.
If you want to shoot 1000, then by all means load hot.
 
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