Long range load development at 100 yards.

[sbranden]

Wow, this has been a great (and very long) read! But I took a lot of good notes that I hope will help me a lot going forward now.

Allow me to ask some even more basic questions though as somebody still relatively new to reloading. For example, when I first got a 22-250 - I used factory ammo for barrel break-in, then being impressed with what I saw I wanted to move quickly ahead to find a load I could hunt with. So I took Nosler custom brass, Berger 52 match target hollow points, and loaded up charges with both Reloder 15 & Varget. Found gold at 36.5 of Varget, but this was simply using "Book COL", 2.350". I did a similar thing later then with Varget and Sierra's 55gr Blitzkings. The accuracy node seemed to be 35.8 - 36.0, so I just went with 35.9, again at the published COL/OAL. So now my question is... if I already seem to have a good charge, can I simply take 35.9 and try your depth testing recommendation now going from -.010 out to -.030 or whatever? Or do I need to go back and re-test charges again at .020 or .025 off first?

 

[mac86951]

Wow, this has been a great (and very long) read! But I took a lot of good notes that I hope will help me a lot going forward now.

Allow me to ask some even more basic questions though as somebody still relatively new to reloading. For example, when I first got a 22-250 - I used factory ammo for barrel break-in, then being impressed with what I saw I wanted to move quickly ahead to find a load I could hunt with. So I took Nosler custom brass, Berger 52 match target hollow points, and loaded up charges with both Reloder 15 & Varget. Found gold at 36.5 of Varget, but this was simply using "Book COL", 2.350". I did a similar thing later then with Varget and Sierra's 55gr Blitzkings. The accuracy note seemed to be 35.8 - 36.0, so I just went with 35.9, again at the published COL/OAL. So now my question is... if I already seem to have a good charge, can I take 35.9 and now try depth testing from -.010 out to -.030 or whatever? Or do I need to go back and test charges again at .020 or .025 off first?

As long as you are keeping the bullet off the lands, you should be good with your current charge. By increasing case volume (and decreasing jump) you will lower pressure. Go forward from COL in increments of ~0.010 until you find a sweet spot, then you might narrow down the 0.010 further with 0.003(ish). Once you are at a node for COL, and you are using your old working powder charge, you'll want to re-check the powder charge again. It should be close to your original node, usually up a little .2-.6grs, but check both ways to be sure.

-Mac

 

[Erik Cortina]

Wow, this has been a great (and very long) read! But I took a lot of good notes that I hope will help me a lot going forward now.

Allow me to ask some even more basic questions though as somebody still relatively new to reloading. For example, when I first got a 22-250 - I used factory ammo for barrel break-in, then being impressed with what I saw I wanted to move quickly ahead to find a load I could hunt with. So I took Nosler custom brass, Berger 52 match target hollow points, and loaded up charges with both Reloder 15 & Varget. Found gold at 36.5 of Varget, but this was simply using "Book COL", 2.350". I did a similar thing later then with Varget and Sierra's 55gr Blitzkings. The accuracy note seemed to be 35.8 - 36.0, so I just went with 35.9, again at the published COL/OAL. So now my question is... if I already seem to have a good charge, can I take 35.9 and now try depth testing from -.010 out to -.030 or whatever? Or do I need to go back and test charges again at .020 or .025 off first?

If you are at the middle of the node you should be fine after seating depth testing.
Find the lands and start off .005" off the lands. Then seat bullet deeper .003" for every group until you find the sweet spot. I like to see at least two consecutive seating depths with small groups to be satisfied.

 

[sbranden]

Great thanks. I will try taking what appears to be my middle of the road charge in what is probably my high end accuracy node for Varget with the 55BK's in my 22-250, and seat to .005 off and then back up from that in .003's. I may be a long time getting to this, but I will try to report back later this summer.

You recommend full length sizing, but I went down the neck sizing trail with my reloading. Lee collets w/Redding competition seaters mostly.

Should we weigh bullets? weigh cases? sort cases by length for groups? or sort bullets by length, or by measurement to the ogive?

Any other details you can provide about your 'process', and things to do in order of importance would be much appreciated. Again, this has been a very great read. Thanks for doing this.

 

[Erik Cortina]

Great thanks. I will try taking what appears to be my middle of the road charge in what is probably my high end accuracy node for Varget with the 55BK's in my 22-250, and seat to .005 off and then back up from that in .003's. I may be a long time getting to this, but I will try to report back later this summer.

You recommend full length sizing, but I went down the neck sizing trail with my reloading. Lee collets w/Redding competition seaters mostly.

Should we weigh bullets? weigh cases? sort cases by length for groups? or sort bullets by length, or by measurement to the ogive?

Any other details you can provide about your 'process', and things to do in order of importance would be much appreciated. Again, this has been a very great read. Thanks for doing this.

Based on the highlighted statement I feel it would be futile to answer the other questions.

 

[sbranden]

Erik, the decision to neck size and then use a higher grade seater die was made -- right or wrong -- long before (a few years in fact!) I ever read this thread, so don't feel like I intentionally ignored your good advice. Neck sizing eliminates case lube before full length sizing, was said to be easier on brass, was said to increase accuracy, etc., at least based on my research at the time when I was first getting into reloading.

I've always wondered about these other steps and how much good they could do for me (or how much extra wasted time it would add to my process for little to no ROI). I should think they would still matter -- or not matter -- equally though, regardless if full length or just neck sizing.

Anyway, thanks or sharing.

 

[GarethMarijt]

Hi, I was wondering if I could get your advice?
This was shot in blustery conditions, generally between 10 and 15 mph. I am using a Remington 700 in an AI stock, 308 calibre. The bullets are 155 Palma SMKs over N140



43.0 grains seems to be the best, but 44.0 also looks good, but is only 0.2 grains away from maximum. Any suggestions gratefully appreciated.

Kind regards
Gareth

 

[6BRinNZ]

Gareth - it is hard to interpret the target, in part because the powder increases go from .4, .2, .4.

There is a lot of information about individual groups but what you are looking for is a consistent (vertically) group centre between powder charge increases, this information coupled with reliable chronograph settings is the foundation of the 100 yard approach in the thread.

Your comments seem like you are looking at the vertical within a group as opposed to vertical centres between groups (powder increases).

Posting the native targets will make interpretation a lot easier.

Within reason don't worry too much about group shape at this early point, look for consistent POI of centres and ideally a flattening of the chrony numbers between consistent powder increases. This would produce the powder charge to work with. Group shape can then be improved with things like seating depth. Seating depth can have a dramatic impact on group shape.

Personally I'm sold on seating depth and a tuner for the ultimate in group shape but that is another story....But Erik can help on that one as well

 

[panzer075]

so I tried this out with my new brux barrel with New brass...got pretty consistent results which made it a little hard for me to read...

I think I have a good node between 43.7-44.3. 1 round was pulled a little high on the 43.7 group which would bring it down a little, but even as is it seems to fit in..

I am thinking to do my seating depth test with 44g...but wanted to see what the consensus is..

 

[6BRinNZ]

so I tried this out with my new brux barrel with New brass...got pretty consistent results which made it a little hard for me to read...

I think I have a good node between 43.7-44.3. 1 round was pulled a little high on the 43.7 group which would bring it down a little, but even as is it seems to fit in..

I am thinking to do my seating depth test with 44g...but wanted to see what the consensus is..

IMO there is POI change in the range you listed...to me 42.4 - 42.7 and 43.1 - 43.4 look good. You could make a case for 42.4 - 43.4 but I think that 43.1 and 43.4 have risen just a touch compared to the two lower charges.

Chrony numbers would help make a case here.

 

[jsthntn247]

so I tried this out with my new brux barrel with New brass...got pretty consistent results which made it a little hard for me to read...

I think I have a good node between 43.7-44.3. 1 round was pulled a little high on the 43.7 group which would bring it down a little, but even as is it seems to fit in..

I am thinking to do my seating depth test with 44g...but wanted to see what the consensus is..

It looks like two nodes at 43.1 and 44.6. What I really want to know is how you acquired 3 8lbers of varget however.

 

[BSlagle]

Erik,

Could you give me your thoughts on this test?

Specs:
6mm Dasher
Lapua brass
105 Berger Hybird
R-15
BR-4

Top row: 32.0gr, 32.5gr, 33.0gr,
Bottom row: 33.5gr, 34.0gr

I am thinking 33.5gr

 

[Erik Cortina]

I would try 33.2 since 33.0 and 33.5 line up.

 

[BSlagle]

Thanks Erik

 

[fspitzdorf]

I think this is actually my first post here, so...

My submission for the initial step of this exercise.

Remington 700 SPS Tactical in a B&C #3 with a Rifle Basix trigger.
223 Remington
R-P Brass
CCI BR4
Reloader 15
69 SMK loaded .010 into rifling.

It is not shown in this photo but I did the layout for group center lines and have 2 groups next to each other with the same vertical distance to aim point (as close as I can approximate with calipers).

Need to perform the seating exercise next. maybe today.

 

[Erik Cortina]

I'm thinking between 23.6 and 23.9

Welcome to the forum.

 

[fspitzdorf]

Aim point was the small square in each instance. Group centers vertical distance:

23.3 - 1.600
23.6 - 1.365
23.9 - 1.460
24.2 - 1.300
24.5 - 1.430
24.8 - 1.430
25.1 - 1.240
25.4 - 1.300
25.7 - 1.450
26.0 - 1.530

I chose 24.7 since the group was vertical at 24.8. Guess we will see.

 

[6BRinNZ]

Aim point was the small square in each instance. Group centers vertical distance:

23.3 - 1.600
23.6 - 1.365
23.9 - 1.460
24.2 - 1.300
24.5 - 1.430
24.8 - 1.430
25.1 - 1.240
25.4 - 1.300
25.7 - 1.450
26.0 - 1.530

I chose 24.7 since the group was vertical at 24.8. Guess we will see.

Chrony numbers can be quite useful to help guide the decisions with this approach. From what I can tell a flattening of FPS combined with no change in vertical POI and powder charge increases is utopia.

 

[panzer075]

So I have a dilemma.... so i reran my powder test and found I had a good node from 44-44.4g.

I did a seating depth test from .005 off to .030 off...44.2g

I get a few great groups...but my ES were quite high with all of them. I would get 3 shots same velocity and 1-2 would be 20+ fps out....

I had one 4 shot group that was good and it had an ES of 8 but I couldn't duplicate it the 2nd test...

I know the system works my other rifle I developed a load with an ES of 4 for 15 shots...

But this new Brux barrel has me stumped... I seem to have a wider powder node and a tiny seating depth node....

Would more neck tension or diff primers help?

Any opinions welcome

 

[6BRinNZ]

So I have a dilemma.... so i reran my powder test and found I had a good node from 44-44.4g.

I did a seating depth test from .005 off to .030 off...44.2g

I get a few great groups...but my ES were quite high with all of them. I would get 3 shots same velocity and 1-2 would be 20+ fps out....

I had one 4 shot group that was good and it had an ES of 8 but I couldn't duplicate it the 2nd test...

I know the system works my other rifle I developed a load with an ES of 4 for 15 shots...

But this new Brux barrel has me stumped... I seem to have a wider powder node and a tiny seating depth node....

Would more neck tension or diff primers help?

Any opinions welcome

You seem fairly set on the 44 range - but in your original test I'm not convinced that was all that good - you sure that the powder range you have selected isn't the cause of your issue?