Help rookie with reloading and shooting data

[pbroski]

In my experience, seating depth can take a 3" group to a >1" group.

Can you show us some examples of this? Genuinely intesrested.

 

[Legend]

Yeah I used to believe that subtle things like seating depth good make inorovements as well. Those were 3 or 5 shot groups and it was just coincidence.

As soon as you shoot statistically significant groups...large sample size, then those observations disappear. Hornady has a podcast on it, which I realize they are biased, but held accurate for me. YMMV

 

[EdP]

My apologies! Wrong terminology! Idk why I've always called them a "vice." It was a lead sled. I shot from a lead sled.

OK, thanks for clearing that up. Some would argue that shooting using a lead sled is a vice (as opposed to vise).

In my mind, if you are not comfortable handling the recoil, you should either practice until you become comfortable with it or shoot a lower recoiling rifle. Either way, I'm with those who recommend ditching the lead sled. You won't have the lead sled with you in the field so don't let your marksmanship be dependent on it. If the problem is your shoulder getting sore from a high number of rounds, try a PAST pad.

 

[NorthIdahoDude]

Just to see what you're working with gun wise, I'd suggest you try a 168 Sierra Match King (SMK), seated to about 2.813 (unless that's to long for your chamber, but I've never seen one that it was).

The 168 SMK is consistently the the most accurate bullet I've ever shot in any gun with a .308 bore (30-06, 308 Win, etc), and it shoots great with just about any amount of jump. Those even shoot sub-MOA in my Howa Super-Lite! I don't think I've ever owned a 308 that shot better with something other than 168 SMK's and Varget in well prepped brass.

For powder, N150 is basically Varget with an ever so slightly slower burn rate. In my 308's, I've always found Varget produces noticably better accuracy with 165/168 class bullets than it does with 150's, and given the burn rate of N150, I'd expect it will be about the same in that regard. I've never had bad luck with any VV powders, so I think that's probably good to go, but Varget is the gold standard baseline for 308/168 SMKs.

Anyway - I recommend you try your N150 and 168 SMK's and see what you get. I bet you get some very good accuracy, and then you will have your baseline for how well (or not) other loads shoot in that gun.

The "Easy Load Development" thread is pretty spot on in concept - any given bullet + powder + primer + brass + your loading technique, is probably gonna shoot about how it shoots in your gun. Different combo's can shoot WILDLY different in any given gun also.

Also, I'll re-echo what others are saying - 5 round groups can only tell you if any given load is bad; it's not enough to tell you if it's really good. If you shoot a 5 round group (or even a 3 round group) and think "wow, that sucks", there's basically a 0% chance that group is going to turn around and make you happy if you keep sending rounds. If you shoot a 5 round group that looks nice, all that proves is that those 5 rounds landed close together; you'd need to see a minimum of another 10 before you should get too excited, and another 25 before you start feeling confident about what your+your gun+your loads is capable of. Don't get disapointed if it turns 1.5-2 MOA is all you get - that's all 99% of the hunting-gun class guns is capable of when the round count on group size goes up.

Seating depth is chasing your tail - I have seen guns shoot somewhat better and somewhat worse with seating depth, but you won't turn 3MOA into 1MOA with seating depth, but you might turn 2MOA into 1.75MOA or somesuch.

Powder selection matters a LOT more than I think many people give it credit for. For 150's in a 308 Win, you're probably going to find that powders a bit faster than N150 produce the best groups. Things like H4985, N140, maybe even as fast as H322 or AR-Comp or N13x. My 'money' load back when I ran 150's in a 308 was h4985, and I had experimented briefl with AR-Comp with even better results, but then AR-Comp got hard to come by and I've since moved to 165/168's in all my 308s.

Here's a good example of how much powder selection can matter:


This is 10 rounds of 7x57 Mauser, 162 ELD-X, @ 3.210 OAL, H4350 loaded at 2664 FPS. Not awful, but not impressive either; I'm confident a 30 round group of this would come in arond 2-2.25 MOA.




And this, is also 10 round sof 7x57 Mauser, 162 ELD-X, @ 3.210 OAL, N555, loaded to 2667 FPS, out of the same gun, shot I think 2 days apart. I've drilled 30 rounds of this load into a 1.1 MOA group before. The one and only variable here, is I switched from N555 to H4350.



Anyway, hope all this helps.

 

[HandgunHTR]

Can you show us some examples of this? Genuinely intesrested.

I have personally had three instances. All of them were early in my reloading career.
The first two were with a Remington Model 7 chambered in .260 Rem. Both were with Barnes bullets. I started with them at 0.020" off the lands and could not get any of them to group. I have a background in statistics, so I completely understand the principal of statistical significance. The group sizes for twenty round samples was over 3", regardless of powder or charge. Once I figured out that they needed to jump at least 0.050" my group sized shrunk significantly and I finally settled on a load that over the 300+ rounds fired on paper gave me an average group size of 1.193" for the X bullet load and 0.987" for the XLC load.

The other instance that I had was the other way. I was using 140 grain Nosler BTs in a Browning 7-08. When I loaded them to the same COAL as the factory loads that shot pretty consistently (1.5MOA) I got very erratic results. My notes show that the average group size for five 5-shots groups were 2.875". I chased it for a while and then a friend suggested I load them out to mag length to gains some case capacity and try a bulkier, slower burning powder. I tried that and while I didn't achieve what I was looking for (better than factory accuracy), I did see a marked improvement. When I left the seating depth alone and went back to my original powder, I found that accuracy was much better. Over the course of the next 10 years of shooting that rifle, my overall average group size (5-shot groups) was 1.112" (over 100 samples).

One thing I will say about today's bullets over the bullets of 20+ years ago is that they seem to have a much larger tolerance band when it comes to jump, but to say that seating depth is totally irrelevant, especially considering what it can affect regarding pressures, is a bit of a misconception.

 

[Mike D Texas]

Get rid of the crutch of using a lead sled. They are horrible for many reasons.

Learn to shoot the rifle without it. That’s probably not the biggest contributing factor but it isn’t helping you or the rifle.

Also, for those bullets specifically, .005 is too close, I personally start all new loss at .020” from the lands.

Berger has a pretty good article on load tuning. Don’t get hung up on micro adjustments on seating depths.


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