Load work up...seating depth test first OR charge weight first?

Seating depth first or optimal charge weight first?

  • Seating depth

    Votes: 6 85.7%
  • Charge weight

    Votes: 1 14.3%

  • Total voters
    7
Ok JE where can I find a brisance chart? I spent some time looking last night but could not find anything official. I found a test that was more a less a homemade deal with a pendulum measuring blast force, but it could have some relevance.
 
Or better yet could you post a list of what primers you have found to work best with different powders, or range of burn rate?
 
I start .10" off the lands, do a ladder test with charge wts (increasing .5 gr per shot till I find a node the rifle likes), then fine tune the seating depth from there at .003"-.005" increments.
I typically shoot Bergers & H1000.
 
Or better yet could you post a list of what primers you have found to work best with different powders, or range of burn rate?
This may be of some help:
http://precisionrifleblog.com/2012/07/02/most-accurate-rifle-primers-for-precision-reloading/. But its just part of the story. The rest has to do with how the primer is seated by the reloader ( not deep enough, too deep crushing the priming compound, primers seated to close to same depth in each cartridge ETC) . The condition of the firing pin and spring of the rifle. Its all an ignition "system" so each piece must work correctly.
 
My method is very close to JE. I personally like to shoot not load develop. I also like to get done with as little resource used as possible. Accuracy is a word defined many ways too. The rifle is a big variable here as not all rifles are created equal.

My goal is to find a load at top end that is also at 100% case fill without compressing. I don't like compressed loads for the most part. A little crunch is not always bad.

I rely on the chrono heavily during load development. I load develop at my longest oal that is convenient for the rifle. .02" off the lands or to fit the mag. Then when or if I do make a seating depth adj there is only one way to go. I work up my load one charge one shot at a time. I use the same aim point for each charge weight. I like to see uniform increase in vel for each increase in charge weight. If this is not uniform I will change powder. I watch the target for accuracy. If it is all over the place with each increase in charge weight I am suspect and often will make a change in powder then. The biggest thing here is uniform or predictable increases in vel for the increase in powder. I like to predict the vel for the next charge prior to the shot. When the vel increases predictably it almost always finishes with very good sd.

I like to find where pressure starts to show and then back off from it. That way I know that I am not too close to high pressure. Some rifles do not show pressure well. The vel is another indicator of high pressure. If your vel is off the chart so is your pressure.

Once I find the top end I will shoot 3 or 4 more to see that sd is good and get an average vel. I then get rid of the chrono (magspeed). Now I will shoot for a group. If accuracy is not good (relative term) I will then adj seating depth shorter. And shoot groups at the adj seating depth. If the first two shots are not good there is no point in shooting a 3rd. It won't make the group better. I do this until the accuracy is there.

With our bullets it is very rare that I make a seating depth adj. They don't need it.

Like JE I expect to be done load developing in a relatively low number of shots. I usually find my charge weight in less than 6 shots, another 4 for vel, 3-5 more for a group and zero the rifle. I am almost always done at this point. If I have to change powder it could add a few more shots.

Side note. Most cartridges I make 1g changes in charge weight. Small cartridges with less than 40g of powder I may go to .5g. I never mess with tiny charge weight changes. Only in my 17 Hornet, it only takes 10g of powder.

As a bullet maker it would be better for me to advertise a load development that takes hundreds of rounds but I would rather see my customers enjoy shooting accurately rather than waste time and money chasing a load.

Steve
 
Ok JE where can I find a brisance chart? I spent some time looking last night but could not find anything official. I found a test that was more a less a homemade deal with a pendulum measuring blast force, but it could have some relevance.


I have never found one chart that was the definitive rating for brisance,
But when comparing different charts that are available they appear to be close in the order but just not the same values (The way the test were conducted produced different numbers even though they were In the same basic order). One day I will do my own test and see if it changes the order. (It probably wont, but I would like to see).

I have several Links on my web site describing primers that Might help to understand them better. http://www.castingstuff.com/primer_testing_reference.htm

My own reference that I use goes from hot to cold and looks like this.
Note : This is based on all the info that I have seen and experienced.

Fed 215 M
Fed 215
Winchester LR Magnum
CCI 250
Rem 9 1/2 Magnum
Winchester large rifle
Fed 210
Fed 210 M
CCI BR 2
CCI 200
Rem 9 1/2

Again, based on velocity and pressure changes while working up loads this is my ranking and should be close but not exact.

Also base on many test and tons of data I have come up with a "Rule of thumb" that works most of the time.

Based on powder burn rates and cartridge capacity test have indicated that cases with 10 to 50 grains seem to prefer standard large rifle primers. Cases with 50 to 90 grains may have to be tested with standard or magnum primers, Sometimes the magnum primer will produce the highest velocity, but the poorest SDs. So my experiences
with this has been to try both with reduced loads and if the magnum primer reach the highest velocities but still maintain good SDs then I stay with them. In other test I have found that standard primers got much better SDs with very little loss in velocity, so they became the preferred primer.

With cases that have over 90 grains I have found that Magnum primers are a must. The only choice is the Brisance difference. and then subtle changes in brisance made a difference in accuracy and SDs.

These have been observances over the years and there is no scientific proof, just test results.

Selecting the best primer is not an exact science, but it has a huge impact on total performance. So there is no ONE best primer or a do it all primer if ultimate performance is desired.

Just My opinion and observations

J E CUSTOM
 
Barefoot thanks for the link it was info like many that I looked at. Pretty much all the info I have looked at agrees that Fed and CCI are amongst the best but only one gave any info on the "strength" of a primer.

Another interesting thing is all have shown the match or bench rest grade primers to be better than standard, though I and many on this forum have seen no difference in using them. And it sucks I have yet to see Fed 215 match on the shelves.
 
Barefoot thanks for the link it was info like many that I looked at. Pretty much all the info I have looked at agrees that Fed and CCI are amongst the best but only one gave any info on the "strength" of a primer.

Another interesting thing is all have shown the match or bench rest grade primers to be better than standard, though I and many on this forum have seen no difference in using them. And it sucks I have yet to see Fed 215 match on the shelves.
Don't get stuck on charts. They are really only a "suggestion" in my opinion. You have to test. Back when I shot PALMA I had my best luck with the standard Winchester Large Rifle primers. Don't get stuck on just the primers used by target shooters. They mostly shoot in warmer conditions than hunters. So you may need to do some testing in colder temps also with a hunting load to see what's up. If its one thing that I have learned in all the time I have been shooting and in this industry its that everything can change. From the wind direction to a new barrel , lot of powder, bullets , us "loose nuts behind the butt plate, ETC. As long as you keep that in mind you're good.
 
I want to say thankyou JE and all of you for your vast knowledge and experience.

I have only been at this for a year and am by no means an expert but believe I am at an advanced stage but I wouldn't be there or know half of what I do without all the help on this sight.
 
JE the link you posted is the chart I found last night.

Now along with your rule of thumb on case capacity will you steer more towered one primer over another based on faster or slower burning powder?
So for example a load in my 243 is 47 grains RL26 which is a slower burning powder, would you opt for a couple of the hotter large rifle primers or just test all that you can?
 
JE the link you posted is the chart I found last night.

Now along with your rule of thumb on case capacity will you steer more towered one primer over another based on faster or slower burning powder?
So for example a load in my 243 is 47 grains RL26 which is a slower burning powder, would you opt for a couple of the hotter large rifle primers or just test all that you can?


At this point if I were you I would look for the most consistent primer
With the same approximate Brisance. You can try going up to see where it leads you and also going down. It's like tuning you primer for optimum performance.

An example of the difference it can make in some cartridges. I had/have a 7/08 that I spent a lot of time working up the best load for because it was to be used in Running Boar matches (Moving targets at 500 Meters) and I needed the most accurate load possible.
There ended up to be only two powder choices and with Rem LR primers it consistently shot .058 to .073 groups @ 100 yards. SDs were averaging .09. I decided to try a match primer (CCI BR2) and the SDs came down to an average of .06 (Not very much) but accuracy average was from .051 to .063 (Again Not Much But A measurable difference @ 500 meters.

Subtle changes may not show much difference at 100 yards, but if you chronograph and keep good records on group sizes it will pay off at longer distances.

Again: I am no expert on primers, I just have lots of experience with them and can not settle for anything less that the best performance.
(I need all the help I can get).

J E CUSTOM
 
I have only been at this for a year and am by no means an expert but believe I am at an advanced stage but I wouldn't be there or know half of what I do without all the help on this sight.

Because you mentioned being new, I figured I would show you what happened with different primers with this particular savage .223 Rem. It had a 26" 9" twist barrel with an .800" muzzle. The next rifles results may come out differently. My objective is to convince fellow shooters to try different primers once they think they have a good load. The primers used are as follows: Federal 205 and 205 M, Remington 7 1/2 Bench Rests, CCI BR 4 and 450 magnum and Winchester WSR. Groups were fired at 100 yards from bags over several days. I used JLK 65 grain bullets.

Federal's 205 made three groups. They measured .519" @ 3220 fps, .962" @ 3224 and 1.216" @ 3210". The 1.216" group had a couple of fliers. They averaged .899" @ 3218 fps. I didn't try more because they weren't worth shooting in this rifle.

The 205 M from Federal is a match primer. There are records for four groups. They show groups of .709" @ 3224 fps, .726" @ 3224 fps, .644" @ 3224 fps, .757" @ 3227 fps. Their four group average was .709" @ 3225 fps. This primer produced the most consistent velocities that I have seen in any fire arm. Consistent velocities did not translate into the best accuracy.

The four Remington 7 1/2 Bench Rest primer's groups measured .744" @ 3211 fps, .682" @ 3211 fps, .676" @ 3224 fps and .682" 3223 fps and averaged .696" @ 3217 fps.

Four Winchester's WSR primers worked as follows: .582" @ 3220 fps, .399" @ 3249 fps, .830" @ 3219 fps and .812" @ 3219 fps. The average is .656" @ 3227 fps. All of the WSR primers were pierced by the firing pin.

Six CCI 450 magnum. It produced .684" @ 3200 fps, .546" @ 3207 fps, .711" @ 3234 fps, .544" @ 3219 fps, .806" @ 3191 fps and .525" @ 3218 fps. The average for the magnum primer was .636" @ 3211 fps.

Five BR 4. We saved the best for last. The groups measured .492" @ 3245 fps, .477" @ 3250 fps, .441" @ 3245 fps, .452" @ 3232 and .460" @ 3229 fps. Its phenomenal five groups average is .464" @ 3240 fps. It also produced the highest velocities.

I did this same test with a Freedom Arms .454. The CCI450 was the best producing five shot groups at 100 yards under 2".
 
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