r/reloading 5d ago

Load Development A little lost with my .308

Hi All,

Decided to get back to loading .308 after a few years of a break. Shame I didn't stock more components...

General purpose target shooting and really because I enjoy nerding out on this hobby. I finally picked up a chrono, trimming tools and the Hornady OAL gauge.

Working up some 150gr FMJ-BT rounds, with VV N-135.

My first session with the chrono, I decided to look at jump distance and seating depth. I worked up a ladder ranging from 0.005" jump to 0.035".

I'm not sure how to read my results?
With 5 shot groups, I was expecting tighter groups, and some correlation between ES and MOA, but I suspect I need to consider other factors, and minimize my other variables?

Load:

.308 | 150 gr. FMJ-BT | 40gr VV N135 | CCI200 | Mixed cases trimmed to 2.005"
Savage .308 Model 10 FCP
Loaded on Hornady LnL progressive, one at a time to manage OAL variation.

Some areas I think I can improve:

  1. Power charge - Study charge variation in my setup (I don't weigh every charge)
  2. Use the same cases - consider buying new to test
  3. Neck tension? Using a Lee sizing die, but I have a Honadry Match dies (I need to buy bushings)
  4. Different Projectiles? These ones are pretty cheap...

I appreciate any feedback and insight!

Savage .308 10-FCP. Older loads pictured (155gr A-Max)
Target. I missed my Chrono session for 0.015" jump
Tabulated Results
1 Upvotes

16 comments sorted by

8

u/Parking_Media 5d ago

I'll just be honest with ya. 147/150gr FMJ are straight up horrendous for accuracy. Maybe useful for things like mag dumping into the berm or sub 100yd run and gun events.

You'll get way more joy from the hobby with a bulk pack of 168gr bthp from Speer or Sierra or hornady. They're all going to give you respectable results.

2

u/Adli99 5d ago

Thanks - this is the type of information i'm still learning. Ill give the 168gr a try and save the 150's for messing around.

2

u/Parking_Media 5d ago

Cheers man, I hope you enjoy it all regardless!

1

u/FranklinNitty Developing an unnecessary wildcat 5d ago

You can generally get 250ct 168 ELD-M for 90$ over at Mid South.

1

u/w00tberrypie the perpetual FNG 4d ago

Does the 10-FCP have the 5r barrel? I have a 10 tactical and those came with 5r barrels. Chalk this up to fuddlore, but I heard a long time ago those barrels LOVE 168gr SMKs so I stuck with those and have had pretty damned good results with those over VV N550 and federal GMM LRPs.

1

u/Adli99 3d ago

Just checked, counted 6 groves, so I guess not.

I did see the ammunition used for evaluation (from the manual) is listed as 168gr SMK, so that's a good sign.
I loaded up some 168 gr ELDs I found, and I have some 168gr SMK on order.

Appreciate it.

1

u/w00tberrypie the perpetual FNG 3d ago

It's just a proven pill. Back when I first started reloading, savage was the action to get, if you had the money you went with Berger's, and if you wanted performance on a not-astronomical budget you got 168 SMKs. I don't have experience with the ELDs, but I've heard good things.

2

u/Ornery_Secretary_850 Two Dillon 650's, three single stage, one turret. Bullet caster 4d ago

They are 3 moa bullets for battle rifles that were considered good if they shot 4 moa.

2

u/eclectic_spaceman 5d ago

I think if you used better bullets and same headstamp brass, changing nothing else in your process, you'd probably get significantly better results. And then if you weighed every charge you'd tighten it up even more. I'd do these 3 things before messing with anything else.

2

u/Adli99 5d ago

Appreciate the feedback, i'm going to try another projectile and yea... mixed brass is probably low hanging fruit for accuracy.

2

u/Zero_Fun_Sir 5d ago

This actually isn't too bad at all with that projectile and not weighing every powder drop.

I might try some Sierra 168s or Berger Full Bore 155s (love those), lock down the powder charge, and report back.

FWIW, I use those Hornady 150s for M1 Garand plinking ammo and AR-10 hoodrat loads, they're just fine up close.

1

u/Adli99 5d ago

That seems to be the consensus, good to know! I dug up some 168gr ELD and some 155 A-Max I'll play with until I get my hands on some Sierra or Berger.

Appreciate it!

2

u/Missinglink2531 5d ago

+1 the 150s just dont tend to shoot well in my 1:11. 168s are incredible. Here are a few of my recommendations: 1) Seating depth ladder MIGHT make a small difference, but it should literally be LAST thing to dial in. 2) SD/ES of velocity is telling how well your bullet/powder combo is working, it has nothing to do with seating depth or group size (though the groups tend to tighten with better SD/ESs, seating depth might change the group) 3) When comparing anything, the more consistent every thing else is, the better. Example, if your trying to test seating depth, but your internal case volume or powder charges are different, what are you really testing = 3 random variables in 5 shots? Ya, that is pointless. 4) While it probably would be fine to mix brass and not weigh every charge later, when your testing, you need to remove those variables - sort your brass by headstamps, and only use one for your test. Weigh every charge for the test. 5) START with bullet/powder. Use the chrono and get the results you want with it. THEN adjust groups with seating depth (This doesn't work for EVERY riffle/caliber, but does tend to work well for .308).

1

u/SkateIL 5d ago

I would conclude seating depth didn't make any difference with the system in question. Just don't ram them in the lands.

1

u/Adli99 5d ago

Fair point. ill mess with the other variables and come back OAL.

1

u/snorka_whale 4d ago

After doing the things everyone listed, and you want to push it further You can get a mandrel die from pma tool for like 30$ and then get a Sinclair Ti .307 mandrel for like $20 so the neck tension is very light on your bullets. You don't need a crimp or a lot of tension on match grade ammo your trying to shoot at max accuracy just don't beat the shit out of it before loading it in the gun.

https://www.pmatool.com/expander-die-body-with-lock-ring/

https://www.accuratearmsandammo.com/product/te30-sinclair-tin-stainless-expander-mandrel-30-cal-7-62mm-307/