Seating depth - does it even matter?

[huntnful]

I've had some weird results with ADG as well. Lapua or bust honestly. Just hard to get these days but it's worth the trouble. Another Finnish standout.

I have all alpha for my 6CM and 22CM and it seems to be good stuff as well. But Lapua is so damn good if you can get it.

 

[Harvey_NW]

My ADG 7 PRC brass is inconsistent as well. Also .003 neck thickness differences between lots. Junk lol.

I have 500 pieces of Lapua pre-ordered when it drops early next year.

I've had some weird results with ADG as well.

Well sh*t, that's not what I wanted to hear. I never went mad scientist measuring my 6.5 ADG brass, but it's been fantastic. That's what I'll be shooting in my 7 when it shows up so I guess we'll see! I am a bit archaic though, I mean I still use the cheapest grade Hornady FL die sets and expander balls

 

[huntnful]

Here is a small change of only .005 in seating depth.

7 shots in each group






I’m kidding. Just wanted to stir you guys up . This is just testing 195 Berger’s.

H1000 on the left. N565 on the right.

I’d much rather spend 5 minutes testing powders for the major gains. Instead of 5 hours testing depths.

 

[Harvey_NW]

Here is a small change of only .005 in seating depth.

7 shots in each group

View attachment 987935




I’m kidding. Just wanted to stir you guys up . This is just testing 195 Berger’s.

H1000 on the left. N565 on the right.

I’d much rather spend 5 minutes testing powders for the major gains. Instead of 5 hours testing depths.

Dirtbag I hate how H1000 will do that though, start to cluster up and then all the sudden go wild. Prime example of why you need more than 5 to put stock into the results!

Here's the exact same test where it did it to me in 6.5 PRC, pressure ladders on the left, 1gr under pressure signs on the right. 10 shots in each proof group.

 

[huntnful]

Dirtbag I hate how H1000 will do that though, start to cluster up and then all the sudden go wild. Prime example of why you need more than 5 to put stock into the results!

Here's the exact same test where it did it to me in 6.5 PRC, pressure ladders on the left, 1gr under pressure signs on the right. 10 shots in each proof group.
View attachment 988073

Yeah mine actually went back forth a little. Stack a couple, throw one, stack a couple more, throw another one. Super easy to think “am I causing this?”. But then a quick change of powder and putting 7 shots into a .5 shows that it isn’t you. Just that bullet and powder combo doing weird shit.

 

[solarshooter]

Yeah mine actually went back forth a little. Stack a couple, throw one, stack a couple more, throw another one. Super easy to think “am I causing this?”. But then a quick change of powder and putting 7 shots into a .5 shows that it isn’t you. Just that bullet and powder combo doing weird shit.

This is why I always advocate for 10 minimum.

Dirtbag I hate how H1000 will do that though, start to cluster up and then all the sudden go wild. Prime example of why you need more than 5 to put stock into the results!

Here's the exact same test where it did it to me in 6.5 PRC, pressure ladders on the left, 1gr under pressure signs on the right. 10 shots in each proof group.

There is absolutely some weird and very important stuff going on in the chamber and barrel that I've never heard a good explanation for. If it was a simple as bullet and velocity, we should see every combination loaded to the same velocity print the same group. But I have seen and tested many times that changing powder can have a massive change in group size. Or primer. Case and bullet quality have an impact too, but that makes more sense because there are dimensional or mass irregularities that have a direct physical impact on dispersion. But powder and primer type are real weird ones to me.

 

[Harvey_NW]

There is absolutely some weird and very important stuff going on in the chamber and barrel that I've never heard a good explanation for. If it was a simple as bullet and velocity, we should see every combination loaded to the same velocity print the same group. But I have seen and tested many times that changing powder can have a massive change in group size. Or primer. Case and bullet quality have an impact too, but that makes more sense because there are dimensional or mass irregularities that have a direct physical impact on dispersion. But powder and primer type are real weird ones to me.

hArMoNiCs BrUh . Yeah it is crazy to see. I haven't done a ton of primer testing, but in the little I have I didn't see much difference in group sizes, maybe some difference in avg velocity. I would imagine a LR vs LRM primer could produce different results though.

 

[solarshooter]

hArMoNiCs BrUh . Yeah it is crazy to see. I haven't done a ton of primer testing, but in the little I have I didn't see much difference in group sizes, maybe some difference in avg velocity. I would imagine a LR vs LRM primer could produce different results though.

The Fundamental Problem in precision shooting. If I was a rich guy I'd get Brian Litz to study this with a whole team of scientists, engineers, and precision shooters lmao. Which is probably why I'm not a rich guy...

 

[AM_Hunter]

Yeah mine actually went back forth a little. Stack a couple, throw one, stack a couple more, throw another one. Super easy to think “am I causing this?”. But then a quick change of powder and putting 7 shots into a .5 shows that it isn’t you. Just that bullet and powder combo doing weird shit.

What caliber was this with? Ive been having similar issues my 300 PRC and H1000. Hadn't considered switching powders yet but may look into it since im out of H1000. Would N565 be a good or bad choice?

 

[huntnful]

What caliber was this with? Ive been having similar issues my 300 PRC and H1000. Hadn't considered switching powders yet but may look into it since im out of H1000. Would N565 be a good or bad choice?

That’s a 7-300 NMI.


If the gun isn’t shooting how you want it to, trying new powders is definitely a great option. Or a new bullet. N565 is a great powder to interchange with H1000. Basically just add 1gr. more than your H1000 load and shoot it.

 

[AM_Hunter]

That’s a 7-300 NMI.


If the gun isn’t shooting how you want it to, trying new powders is definitely a great option. Or a new bullet. N565 is a great powder to interchange with H1000. Basically just add 1gr. more than your H1000 load and shoot it.

Thanks, ill see if i can find it available anywhere.

 

[BBob]

If it’s getting poor or funky results I’d always switch up powders first. Don’t fight it just do it. Second I’d swap out the bullet.

 

[huntnful]

Roughly .010 off the lands. 7 shots.

195 Berger’s with N568.

83-89gr. and 2914-3094fps.

 

[Harvey_NW]

Roughly .010 off the lands. 7 shots.

195 Berger’s with N568.

83-89gr. and 2914-3094fps.

View attachment 994845

 

[huntnful]

View attachment 994847

Lmao . Sad thing is I don’t even want to hunt with the gun. I’m just shooting it cause I’m bored right now lol

 

[Plainsman-147]

My seating depth test with .223 65gr Sierra SBT. Seating depth starting at .010” off lands and in increments of .003” with 5 shot groups.

My takeaway is the bullets seem to prefer to be closer to the lands, but not definitive yet.

 

[solarshooter]

My seating depth test with .223 65gr Sierra SBT. Seating depth starting at .010” off lands and in increments of .003” with 5 shot groups.

My takeaway is the bullets seem to prefer to be closer to the lands, but not definitive yet.

What makes you say that? Have you even measured the groups? All these groups look the same, certainly close enough that 5 shots is telling you nothing here.

As a test, take what you would call your best load and what you would call your worst, load 10-15 of each, and shoot into one group each.

 

[Plainsman-147]

What makes you say that? Have you even measured the groups? All these groups look the same, certainly close enough that 5 shots is telling you nothing here.

As a test, take what you would call your best load and what you would call your worst, load 10-15 of each, and shoot into one group each.

The first 4 groups were roughly .75” or less, then it seems to open up to 1.0” ish for the next 5, then the last one was right at .4”.

Definitely get the point of increasing sample size as 5 may not tell much of a story, that’ll be an interesting test.

 

[solarshooter]

The first 4 groups were roughly .75” or less, then it seems to open up to 1.0” ish for the next 5, then the last one was right at .4”.

Definitely get the point of increasing sample size as 5 may not tell much of a story, that’ll be an interesting test.

Reading again and I see now you have two groups of five at each seating depth. Can you visually overlay these?