Seating depth?

[Onyx Z]

I tested out some reloads in my rifle and could not find an accurate load through all of my tests. I did however find a load that had a perfectly horizontal group, but it was 4" wide. The wind was blowing, but I doubt it was enough to worry about. Theoretically, should seating depth tighten this group?

Specs:
16" Carbine DD S2W 300BLK barrel
1-4x scope
GI trigger (possible culprit)
SMK 125gr
17.2gr H110
COL 2.240
223 converted brass

[ICANHITHIMMAN]

I tested out some reloads in my rifle and could not find an accurate load through all of my tests. I did however find a load that had a perfectly horizontal group, but it was 4" wide. The wind was blowing, but I doubt it was enough to worry about. Theoretically, should seating depth tighten this group?

Specs:
16" Carbine DD S2W 300BLK barrel
SMK 125gr
17.2gr H110
COL 2.240
223 converted brass

SMK bullets is not very sensitive to setting depths. You will have better luck with charge weights, if you did that already and still did not achieve the results you wanted then start changing components one at a time. I would start with primers, then powder then bullets, then brass.

Jon

[KUSA]

It is likely trigger control or possibly inconsistent cheek weld.

Sent from my Galaxy S3 using Tapatalk 2.

[Onyx Z]

I forgot to put that the gun has a GI trigger, which very well could be the culprit. Geissele coming soon!

I should probably wait on the accuracy loads until the new trigger is in...

[KUSA]

Excellent choice my friend. I hate shooting an AR without one. It really spoils you.

Sent from my Galaxy S3 using Tapatalk 2.

[markm]

Horizontal stringing is typically NOT a load issue. The trigger might be contributing to YOUR errors.

I know I can pull shots wide with GI triggers sometimes.

[Grampsinthesand]

When I am "bumfoodled" by a load not performing consistently....the first thing I do is let a friend shoot my rifle with the loads....then see if he gets the same patterns.
My 40 years of reloading has taught me to suspect powder loads for group size before OAL.

Long time lurker...first post :)

[Coal Dragger]

When I am "bumfoodled" by a load not performing consistently....the first thing I do is let a friend shoot my rifle with the loads....then see if he gets the same patterns.
My 40 years of reloading has taught me to suspect powder loads for group size before OAL.

Long time lurker...first post :)

I agree. When in doubt let a known decent shooter have a crack at it, then if results are still no good run a ladder test.

In fact just start with the ladder test and rounds seated to factory specs.

[tappedandtagged]

I've never had issues shooting badly with a GI trigger. Heck, I pulled off a 4" group with an EO using my reloads and a GI trigger. Scoped, it is sub MOA (barely). I'm not saying a better trigger won't help, but you should be able to get better than a 4" horizontal string with a standard trigger. Are you using bags or a lead sled?

The Sierra bullet is should be a great choice, but sometimes a barrel just won't shoot a particular bullet. A friend loves the 100 grain Hornady Interbond for his .243. Mine won't shoot it at all, but when I changed to the 90 grain Nosler BT, everything came together.

When changing componets, primers are the last thing I look at. First is sorting brass, then the bullet, then the powder then primers. (Of course this is assuming you're using good primers of domestic manufacture i.e. CCI, Federal, Remington).

Go buy some factory rounds (assuming you can find them) and use it as a baseline.

[Onyx Z]

I was shooting from bags. I did shoot a buddies 110gr VMax handloads, and it was right around an inch@100yds, so those were pretty accurate.

Here's my load:
125gr SMK
17.3 gr H110
CCI 400
Assorted brass (300BLK, 223, 5.56)
2.240 COL

I should probably put a higher power scope on it until I find an accurate load. A 1-4 scope and a GI trigger doesn't seem to work very well for this. I'm sure the brass could make a slight difference, but I'm working with what I have and what's available.

[ICANHITHIMMAN]

I was shooting from bags. I did shoot a buddies 110gr VMax handloads, and it was right around an inch@100yds, so those were pretty accurate.

Here's my load:
125gr SMK
17.3 gr H110
CCI 400
Assorted brass (300BLK, 223, 5.56)
2.240 COL

I should probably put a higher power scope on it until I find an accurate load. A 1-4 scope and a GI trigger doesn't seem to work very well for this. I'm sure the brass could make a slight difference, but I'm working with what I have and what's available.

Ditch the assorted brass thing, run one manufacture. What your doing is fine for range fodder but not if your trying to get accuracy beyond the 4 stated inches.

[shootist~]

I was shooting from bags. I did shoot a buddies 110gr VMax handloads, and it was right around an inch@100yds, so those were pretty accurate.

Here's my load:
125gr SMK
17.3 gr H110
CCI 400
Assorted brass (300BLK, 223, 5.56)
2.240 COL

I should probably put a higher power scope on it until I find an accurate load. A 1-4 scope and a GI trigger doesn't seem to work very well for this. I'm sure the brass could make a slight difference, but I'm working with what I have and what's available.

Then the first thing I would do is mimic your buddy's load 100% in your loads using your reloading gear and see what happens; even if I had to borrow or trade for some of his components. If still good, a change to his power is warranted, while using your existing bullets/primers, (if it's a different powder). If accuracy is still poor, you have something going on in your loading procedure or gear.

Scope issues are unlikely if you got good groups with the other ammo; but checking the tightness of mount and screws is always good when accuracy issues appear.