QUESTION about 308 loads

KnotRight

KnotRight

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QUESTION: and I think that a chrono will give me the answer.

I went to the range today to zero in my 308 bolt action Savage at 100 yards. The temp was about 57 degrees and I was shooting 150 grn FMJ and 168 grn V-Max. The 150 was loaded with 42.3 gn of Varget and suppose to be 2600 ft/sec. The V-Max was loaded with 41.7 gn of Varget and suppose to be 2500 ft/sec. (per manual)

The ballistic calculator say the 150 at:
200 yards 2.00 adjustment needed 2.00
300 yards 5.00 adjustment needed 5.75
400 yards 8.70 adjustment needed 9.75
500 yards 12.90 adjustment needed 15.00

The ballistic calculator says the 168 at:
200 yards 1.75 adjustment needed 1.75
300 yards 4.50 adjustment needed 4.75
400 yards 7.70 adjustment needed 7.75
500 yards 11.30 adjustment needed 13.5
525 yards 12.3 adjustment needed 14.75

Do you think that the rounds are that much slower than what the reloading manual says it should be with that powder charge?
 
A lot of variables with this. Their test rifle vs yours. Brass, primer, etc all factors in. I’ve never gotten the published load FPS. You already know the answer. Chrono.

This is the way.
 
What length test barrel did the test calculatir use ? Most load manuals use data from a longer barrel than the average gun. You are correct a chrono is your best solution
 
The other variable I don't see addressed is barometric pressure. At sea level, air is more dense meaning the bullet slows down faster than it would in higher, less dense air.
 
There’s a magneto for sale in the bst:

NC - Magneto Speed Chronograph

Well this one has seen very little use and I need $$ for a set of LRF bino's.. These sell for $380 new. I am putting this one up for $350 obo.....
carolinafirearmsforum.com carolinafirearmsforum.com
 
The reloading manual is just a reference to the equipment they were using. Your results will vary depending on your equipment and environment.

Get a chronograph.....use your chronograph results along with any other data the ballistics calculator might need to get the most accurate result. The ballistic coefficient of your particular bullet and your altitude can make a big difference in Your results.
 
If the weather hold out this week I am going to take my F1 to the range with a bunch of different rounds to see how they compare to the manual. Have not used the F1 in ages.
 
What was the length of the test barrel versus the length of your barrel? But yeah you can see that much difference.
 
TSConver said:
What was the length of the test barrel versus the length of your barrel? But yeah you can see that much difference.
Click to expand...

Per the Hornady reloading manual it was tested in a Winchester 22" barrel and the Savage also has a 22" barrel
 
Same primers and brass? Twist rate same? A lot of variables. Probably temp and density altitude is the biggest one.

Also I am assuming moa for the data? If so that is less than a .5 in difderence at 500 yards.
 
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TSConver said:
Same primers and brass? Twist rate same? A lot of variables. Probably temp and density altitude is the biggest one.

Also I am assuming moa for the data? If so that is less than a .5 in difderence at 500 yards.
Click to expand...
When checking my ballistic app (Flight Calculator), I had it set for 85 degrees and it was about 55 degrees with wind blowing from 6:00 about 10 mph.
 
@TSConver the adjustment at 500 yards was 4 MOA different which is about 20". I can understand a couple MOA but 4?
 
I don't want to sway you in any way but I think you are running the bottom end of the Varget scale. Heck I run 44.2 grains of Vargay at 55 degrees with a 190gr SMK in a 1/10 twist 26" barrel and am up around 2700-2750fps depending on the temp. I have run it up to 46gr but I was in the don't keep going zone laying in the sun in the summer at Butner. In my experience Vargay needs to be run pretty close to max depending on the accuracy you're getting. You almost can't put enough in the case to overload it. I always always hear crunch when I load with it.

You really need at least two good reloading manuals; a Hogden manual and a Hornady manual to start with. Add .5gr at a time until you are .5gr under max. If it looks like you can safely max it out with good accuracy in average temps you will be good to go. Vargay is very temperature friendly. You also need a chrony or you will drive yourself nuts with your dope data card. If you don't chrono the loads and you start shooting at longer ranges you are going to waste a lot of ammo.


Just my humblest of opinions.
 
I would bet that you’d be surprised how slow your loads are. Published data has always been slow for me. A chrono would tell you for sure.


Sent from my iPhone using Tapatalk
 
@REELDOC I loaded 40 rounds last night at the Hornady max loads and hope to test them this week along with some that are suppose to be loaded 100 ft/sec lower. Just check the batteries in the F1.
 
KnotRight said:
@REELDOC I loaded 40 rounds last night at the Hornady max loads and hope to test them this week along with some that are suppose to be loaded 100 ft/sec lower. Just check the batteries in the F1.
Click to expand...
Just a suggestion, load 5 round each of each charge weight. It saves having to pull bullets. Have you checked your COAL?
 
REELDOC said:
Just a suggestion, load 5 round each of each charge weight. It saves having to pull bullets. Have you checked your COAL?
Click to expand...
Agree......
I have a bunch of different powders and will shoot groups of 5.
 
PART 2: Chrono Day - 308 - Savage bolt action
Every load was trickled. Not sure why I have such a spread in velocity unless it is the brass. It has been fired one to three times and not annealed.


308 Chrono testing 03/10/2021​

Reloading equipment:
RCBS Rock Chucker Press
Hornady Rifle dies
Hornady digital scale (RCBS check weights)
Lyman Powder trickler
RCBS Large drum powder thrower
Chrono F1 Chronograph (last used a couple years ago) Bright blue skies using the sunshades
Distance from muzzle 16 feet

First Load: 165 grn copper red tip. No other data
2,581
2,595
2,572
2,616
2,578 Average 2,588

Second Load: Hornady 150 FMJ. No other data
1. 2,606
2. 2,576
3. 2,572
4. 2,565
5. 2,571 Average 2,582

Third Load: Hornady 168 A-Max Varget 41.7 Book shows 2,500 FT/Sec
2,578
2,489
2,548
2,480
2,573 Average 2,534

Fourth Load: Hornady 165 BTHP Varget 44.0 Book shows 2,700 FT/Sec
2,681
2,667
2,641
2,689
2,641 Average 2,664

Fifth Load: Hornady 168 Match Varget 41.7 Book shows 2,500 FT/Sec
2,473
2,463
2,512
2,498
2,559 Average 2,501

Sixth Load: Hornady 150 FMJ Varget 42.6 Book shows 2,600 FT/Sec
2,533
2,590
2,598
2,600
2,604 Average 2,585

Seventh Load: Hornady 150 FMJ Varget 44.8 Books shows 2,700
2,737
2.764
2,733
2,814
2,766 Average 2,763
 
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Neck tension is probably not uniform. From not annealing.


Sent from my iPhone using Tapatalk
 
Zbizzle911 said:
Neck tension is probably not uniform. From not annealing.


Sent from my iPhone using Tapatalk
Click to expand...
I had a Lee melting pot to salt bath anneal but the pot shorted out. Just looked for another one and nobody has them in stock. Also, I went to order some RCBS X-dies and those too are not in stock.
 
Were you checking for accuracy also? Are you showing any pressure signs? Have you trimmed the brass? What are you COAL's for all bullets? What primers? Regular or bushing dies?

rifleshooter.com

308 Winchester load development: Sierra 168 gr. MatchKing with IMR 4064 and VARGET

In the days before the 175 gr. Sierra MatchKing (SMK), the 168 SMK ruled supreme in the 308 Winchester. Back then it was sometimes referred to as a “heavy match” bullet since it was a…
rifleshooter.com rifleshooter.com


accurateshooter.com/cartridge-guides/308win
 
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KnotRight said:
I had a Lee melting pot to salt bath anneal but the pot shorted out. Just looked for another one and nobody has them in stock. Also, I went to order some RCBS X-dies and those too are not in stock.
Click to expand...
Also I'd about bet that you had a few over charges and didn't know it. Most of the regular powder scales only measure down to .2 gr so it may of shown 44.8 but could've been over that and scale didn't show it.
 
REELDOC said:
Were you checking for accuracy also? Are you showing any pressure signs? Have you trimmed the brass? What are you COAL's for all bullets? What primers? Regular or bushing dies?

rifleshooter.com

308 Winchester load development: Sierra 168 gr. MatchKing with IMR 4064 and VARGET

In the days before the 175 gr. Sierra MatchKing (SMK), the 168 SMK ruled supreme in the 308 Winchester. Back then it was sometimes referred to as a “heavy match” bullet since it was a…
rifleshooter.com rifleshooter.com


accurateshooter.com/cartridge-guides/308win
Click to expand...
REELDOC, I was just checking velocity with different loads compared to the Hornady Reloading Manual. I think that I shot around 35 to 38 rounds today. That brass in now in the tumbler for a few hours. Was hoping to use my RCBS dies to reload them but the spindle is screwed up. Going to use the Hornady FL dies. Will check the case length after resizing them. I still have some Varget left and Hornady 165 Match Point bullets. I am going to ladder 3 or 4 rounds starting at 41.5 grns of powder then going up by .2 of a grn. Once I figure out the sweet spot in SD, I will try them out for accuracy.
The problem that I/we have is I can not get the bullets that I want to shoot. Besides the Matich Bullets, I have some 150 FMJ bullets that I will screw around with on steel. Again, I need to feel good that I know the true velocity of the bullets. Also, I am hoping to be able to shoot my loaded bullets over another chrono.
 
Look up optimal charge weight method. It is much faster and better than ladders.


Here is a load I did for 223. 4 rounds at each target following Dan Newberrys Ocw method. Center target is a great node. Less than .25in.

20210307_152029.jpg
 
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KnotRight said:
REELDOC, I was just checking velocity with different loads compared to the Hornady Reloading Manual. I think that I shot around 35 to 38 rounds today. That brass in now in the tumbler for a few hours. Was hoping to use my RCBS dies to reload them but the spindle is screwed up. Going to use the Hornady FL dies. Will check the case length after resizing them. I still have some Varget left and Hornady 165 Match Point bullets. I am going to ladder 3 or 4 rounds starting at 41.5 grns of powder then going up by .2 of a grn. Once I figure out the sweet spot in SD, I will try them out for accuracy.
The problem that I/we have is I can not get the bullets that I want to shoot. Besides the Matich Bullets, I have some 150 FMJ bullets that I will screw around with on steel. Again, I need to feel good that I know the true velocity of the bullets. Also, I am hoping to be able to shoot my loaded bullets over another chrono.
Click to expand...
My final thoughts..........

FWIW I still think you are at the bottom the charge weight and may want to start increasing a 1/2 grain at a time until you see good accuracy without pressure issues. You have the starting charges but may need to venture up. Quit worrying about the chrono until the moon and stars align when accuracy crosses the pressure limit. Finding out the fps of a certain load don't mean much if it isn't accurate. Go from 5 to 3 rounds, find the top two accurate three round loads and then work on them. Putting 3 in the same hole during initial testing is the same as 5 in the same hole.

As mentioned before, you need to know your maximum COAL for your rifle for each bullet you are testing. Back off the lands .020 or to mag length. Pressure varies with the amount of bullet you have shoved in the brass. Make sure your brass is trimmed to proper length. Since you don't have bushing dies your neck tension issue is not in play.

OCW is a good system but shooting round-robin (anytime you are comparing loads) is the key. This allows each round per load to shoot progressively through the barrel heat and cleanliness. Another way is to clean the gun, fire your rounds, let it cool, clean it again and fire the next rounds. Constancy is the key.

And after all that is said and done you have to run dope on the temperatures in the four seasons. I test at 30, 50, 70 and 90 degrees.

Good luck.................
 
REELDOC said:
My final thoughts..........

FWIW I still think you are at the bottom the charge weight and may want to start increasing a 1/2 grain at a time until you see good accuracy without pressure issues. You have the starting charges but may need to venture up. Quit worrying about the chrono until the moon and stars align when accuracy crosses the pressure limit. Finding out the fps of a certain load don't mean much if it isn't accurate. Go from 5 to 3 rounds, find the top two accurate three round loads and then work on them. Putting 3 in the same hole during initial testing is the same as 5 in the same hole.

As mentioned before, you need to know your maximum COAL for your rifle for each bullet you are testing. Back off the lands .020 or to mag length. Pressure varies with the amount of bullet you have shoved in the brass. Make sure your brass is trimmed to proper length. Since you don't have bushing dies your neck tension issue is not in play.

OCW is a good system but shooting round-robin (anytime you are comparing loads) is the key. This allows each round per load to shoot progressively through the barrel heat and cleanliness. Another way is to clean the gun, fire your rounds, let it cool, clean it again and fire the next rounds. Constancy is the key.

And after all that is said and done you have to run dope on the temperatures in the four seasons. I test at 30, 50, 70 and 90 degrees.

Good luck.................
Click to expand...

Yep have to shoot round robin. The ones I showed above were shot round robin with 1 min between each firing to keep barrel temp consistent. There is a node at a slightly lower load and maybe another one above but the center target was really good and the velocity was just north of 2900 FPS which was my target speed for the 224 75gr ELDm bullets out of the 223 bolt gun I just built.
 
With the continuing shortages in ammo and components I try to get every bit of data I can out of every bullet I send downrange. So I use my chrono a lot. I look at SD more than the avg velocity and try to keep it below 10. It's a quick way to check your loads because I think it is a reflection of your overall reloading regime (powder charge, brass condition, neck tension, etc.) A low SD correlates with a consistent velocity across your charge weights and directly impacts your group size. And I shoot at 200 yards (or further). If you have a half way decent rifle it will be a little forgiving with grouping at 100 yards. Some days I get 1/2 moa at 100, sometimes 3/8, and even 3/4 to 1 moa if I'm having a bad day. I'm working up a load for a 7mm right now and with what I had loaded and shot this morning the best 5 shot group was 1.42" at 200 yards (0.68 moa with an SD of 11) which still sucks IMO but it is getting better as my other groups (OCW) with lighter powder loads measured over 2.0" with SD's in the 18 plus range. My goal is 2800 avg velocity with an SD below 10 and shooting 0.5 moa. So, @TSConver is right on the use of the chrono just measuring velocities. And he had a goal in mind too as to velocity. But if you use one check the accuracy nodes with both the velocities and the SD. They usually correlate nicely.

Loading manuals tend to be conservative in their load data and liberal on their velocities. ;)
 
Downeast said:
With the continuing shortages in ammo and components I try to get every bit of data I can out of every bullet I send downrange. So I use my chrono a lot. I look at SD more than the avg velocity and try to keep it below 10. It's a quick way to check your loads because I think it is a reflection of your overall reloading regime (powder charge, brass condition, neck tension, etc.) A low SD correlates with a consistent velocity across your charge weights and directly impacts your group size. And I shoot at 200 yards (or further). If you have a half way decent rifle it will be a little forgiving with grouping at 100 yards. Some days I get 1/2 moa at 100, sometimes 3/8, and even 3/4 to 1 moa if I'm having a bad day. I'm working up a load for a 7mm right now and with what I had loaded and shot this morning the best 5 shot group was 1.42" at 200 yards (0.68 moa with an SD of 11) which still sucks IMO but it is getting better as my other groups (OCW) with lighter powder loads measured over 2.0" with SD's in the 18 plus range. My goal is 2800 avg velocity with an SD below 10 and shooting 0.5 moa. So, @TSConver is right on the use of the chrono just measuring velocities. And he had a goal in mind too as to velocity. But if you use one check the accuracy nodes with both the velocities and the SD. They usually correlate nicely.

Loading manuals tend to be conservative in their load data and liberal on their velocities. ;)
Click to expand...

However good SDs do not correlate to good groups all the time. The speed of the bullet needs to match the harmonics of the barrel.. That is why I use OCW method, it is agnostic of velocity and SD. They usually correlate but it is not a requirement. I have had great groups with SDs in the double digits.
 
I use the OCW method and a chrono as well. Like I said, I try to get as much out of each round as I can. I have never gotten decent groups with high SD's or in high variations in velocity, at least not over time. But once again we digress. :)

 
Downeast said:
I use the OCW method and a chrono as well. Like I said, I try to get as much out of each round as I can. I have never gotten decent groups with high SD's or in high variations in velocity, at least not over time. But once again we digress. :)

Click to expand...


I chrony mine as well but a sd for 3 or 4 round group in OCW method is pretty meaningless statistically. Really need 10 rounds for a good SD estimation.

Gonna chrony 10 tomorrow and get 540 data. So I will let you know how they look. If good gonna true it up at colemans on Sunday.
 
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So ran 10 rounds past the labradar this morning. 2916fps was the average velocity and the SD was 20. This is for 223 bolt gun running 24.6 grains of 8208, CCI 400 primers, everglades ammo 223 annealed new brass and 75gr ELD Match Hornaday bullets. Some would say 20 is unacceptable but it shot a 5 shot group that was .5 in and if I remove the very first shot of the day from that group it is less than .3 in.
 
Went to the range again today with loads of Varget starting at 42.2 going up by ,3 grn to 44.1 grns. The AVERAGE SD for each load went from 27 to 3. I shot 4 rounds at 42.8 grns but forgot to record one of the shots. The other 3 were 2593, 2603 and 2602. That averaged was right at 2,600 ft/sec. After shooting 2 weight groups I let the rifle cool off for 5 or so minutes. My next best ASD was 10 SD and it was loaded with 43.1 grns. Those shots were 2593, 2619,2633 and 2632 for an average of 2619 ft/sec.

Now, I will load around 10 rounds of Varget with 42.8 and 10 with 43.1 to see which one is more accurate at 100 yards and then at 500 yards.

FYI, the rounds shot with 44.1 grns of Varget, the primers were flatten completely.
 
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