Primer Comparison Test

[Poper]

Ok, so in a previous thread I asked a question regarding the possible differences in primers because I believe a change from one mfr to another may have affected the accuracy performance of a previously proven load in a .308 Winchester chambered rifle. I haven't been able to find where someone else has performed a similar test for comparison, therefore, I have decided to devise and perform a test to determine if there is a measurable difference in primers of the same class. I.E. Large Rifle primers.

The setup:
To keep this as simple as possible, I have elected to use a slightly used Weatherby Vanguard bolt action rifle chambered in .30-06 with a 22" barel that has been fitted with a Boyd's "Prairie Hunter" pre-finished walnut stock. Said rifle is equipped with a Redfield 3-9x40 scope in Warne Maxima rings on a Warne Maxima one-piece base. Said rifle has fired less than 200 rounds.

The load is one that has not been fired in this rifle before, so how it will group is anyone's guess, which is exactly why it was selected and exactly why the data gathered by the chronograph should illustrate the differences, if any. It also is slightly higher than the starting load for this bullet and powder combination in the Berger manual but is well below the maximum load for this combination.
All cases will be new, unfired Remington brass, fully prepped, including full length sized, trimmed to length ( 2.484"), chamfered, deburred, primer pockets uniformed, and the flash hole deburred.
Bullets are Berger 155 grain VLD Hunting.
Powder is 53.5 grains of IMR4350.
Cartridge overall length = 3.340"

Loading to be done using a single stage RCBS "Rock Chucker II" press, Redding bushing style full length die, RCBS Competition Bullet Seating Die, RCBS Charge Master 1500 powder dispenser and all charges will be weighed. Primers will be seated using a RCBS Universal Hand Priming Tool.

The Test
To measure the performance as accurately as possible with an amateur's tool box yet with a little bit of sophistication (if that is possible ), I have elected to keep everything as identical as possible with the only variation being the primer manufacturer.
A string of ten test rounds of each primer will be fired over a Shooting Chrony Beta Model chronograph. That data, and that data only, will be used to determine the performance differences, if any. The bore will be be allowed to cool between strings and will also be cleaned between strings. The barrel will be fouled with two rounds prior to firing each string.

I'll endeavor to illustrate with photos if/when practical. With a little luck, I'll be able to run this test this weekend. Stay tuned!

Poper

 

[Rule3]

What primers do you plan on testing?

I would think velocity, average , High/Low , SD and other chrony data only would be the main factors to look at. Accuracy is a whole other variable.

Sounds good, have fun, interested in seeing the numbers.

 

[Lee S. Forsberg]

I did some primer testing a long time ago. I use a different set than you are using. PM me if your interested in what I found out.

 

[Andrew Leigh]

Read this.

http://riflemansjournal.blogspot.com/2009/06/primers-large-rifle-primer-study.html

 

[Rule3]

Read this.

http://riflemansjournal.blogspot.com/2009/06/primers-large-rifle-primer-study.html

Great article and information but way beyond my pay grade!

 

[Poper]

What primers do you plan on testing?

I would think velocity, average , High/Low , SD and other chrony data only would be the main factors to look at. Accuracy is a whole other variable.

Sounds good, have fun, interested in seeing the numbers.

The primer lineup will be the non-magnum primers I have on hand:
1) Remington 9-1/2
2) MagTech 9-1/2
3) CCI-200
4) Winchester LRP

Chrony data I am interested in and will tabulate: Hi, Lo, Extreme Spread, Avg Velocity, Std. Deviation.

I may not have been clear in my reason for this shallow test, so I will state it here:
Question: Is there a significant/measurable difference in the performance of different primers of the same class by different manufacturers in a typical off-the-shelf, out-of -the-box sporting rifle that will significantly or dramatically impact the performance of a proven load in a given rifle?
Reason for question: In the event a particular primer for a proven load in an average casual handloader's recipe is unavailable, will the substitution of a primer of the same class from a different manufacturer perform in a similar manner if all other variables are unchanged?

This is more for the satisfaction of my curiosity than anything else. I'll share the data here with those interested and we can each draw our own conclusions (or not).

Poper

 

[Rule3]

Glad to see you have a proper scientific method going on!

 

[Poper]

Update:

Primer Comparison Test UPDATE:

RIFLE: Weatherby Vanguard / Howa 1500; .30-06 Springfield
LOAD: From Berger Manual, 1st Edition – 51.5 gn (2662 fps) to 57.5 gn (2981 fps)
BULLET: 155 Grain Berger VLD Hunting (weight matched)
CASE: Remington, new, FL sized & trimmed, de-burred, chamfered, flash hole de-burred, primer pocket uniformed.
POWDER: IMR 4350
PRIMERS: Remington 9-1/2, MagTech 9-1/2, CCI-200, Winchester WLR
COAL: 3.340”

Range Conditions:
Ideal; Wind = 0-5 mph from behind, Temp. = 65 deg. to 75 deg., Humidity = 52%
Test rounds were fired at 100 yards in ten round strings with breaks for cleaning and barrel cooling between strings only. Because this was a load never fired in this rifle previously, three zero check rounds were fired. These three rounds were all touching and measured 0.303” center-to-center. Then a scope adjustment of twelve clicks vertical and five clicks right placed the zero point of the next three shot group almost exactly on the aim point. It measured 0.535”. (See attached.) Barrel was cleaned and allowed to cool before firing the first ten round test string. The barrel was cleaned and allowed to cool between each ten round string.

Test string statistics:
There was a cable failure with the first string fired which was the Remington 9-1/2 primers and no data for that string was captured. However, because the sight-in target was so good, all strings were fired for group (sort –of) in that effort was made for proper sight alignment and trigger squeeze, but without great concentration, and were measured center-to-center. The data below is organized with the Target 10-round Group size first followed by the chronograph statistics of High, Low, Average, Extreme Spread and Standard Deviation.

String #1: Remington 9-1/2
G = 1.478”

String #2: MagTech 9-1/2
G = 1.871”
H = 2730
L = 1501
A = 2118
ES = 1228
SD = 1289

String #3: CCI-200
G = 1.119”
H = 2843
L = 2804
A = 2830
ES = 38.87
SD = 12.80

String #4: Winchester LRP
G = 1.759”
H = 2867
L = 1511
A = 2451
ES = 1355
SD = 1302

Conclusions:
When comparing the average velocities, it is evident that a change in primers could affect the impact point of the center of the group in a minor way. Meaning a minor scope adjustment would be necessary for precise bullet placement. However, when looking at the groups and the data together, such a scope adjustment would be very minor, indeed, and the variation within some of the primer strings was enough to account for the entire variation itself.
Additional questions came immediately to mind as I was tabulating the data:
1) Is the data represented by the Winchester string and the MagTech string typical for these manufacturers?
2) Is this wide variation an anomaly specific to these primer lots?
3) Could this variation noted by the chronograph be a characteristic of the way this particular powder works with this particular primer?
4) Would I get similar results if I was to repeat this test?
When I was looking at this data, I reminded myself that the reason I decided to run this test to begin with was the erratic groups my .308 suddenly began throwing when the only change in its proven load was a change in primers, so I took another look at the .308.
Upon inspection: Lo and behold! The front action screw was loose! There is the probable cause of the blown groups.

Poper

 

[ArchAngelCD]

Thank you very much for all the information and taking the time to develop the data.

 

[Poper]

You're welcome, Angel.

I'm not sure it will be repeatable.
However, I am curious enough to run it again just to see if I get similar results.

Poper

 

[rodregier]

My sources indicate RWS LR primers are a very good choice for non-magnum usage.
Good luck finding any.

http://yarchive.net/gun/ammo/308_loads.html

http://yarchive.net/gun/ammo/accurate_primers.html

 

[Andrew Leigh]

Hi Poper,

I am lost;

Your chrony battery must have been getting flat. How on earth is it possible to have a ES of 1228 and 1355, a change in velocity of around 40%. It is impossible to get sub 2" groups with that velocity spread.

Not to mention the STD Dev? If I get a std deviation of more than 20fps I get worried. Are we missing a "." somewhere? If not your battery is a gonner.

I built a small 9V regulator and bought a 12V gelled cell to avert this problem. Used to get so frustrated when you do a bunch of critical load development, spend hours prepping cases and taking care and the data is corrupted by a flat battery.

 

[JRWhit]

Hi Poper,

I am lost;

Your chrony battery must have been getting flat. How on earth is it possible to have a ES of 1228 and 1355, a change in velocity of around 40%. It is impossible to get sub 2" groups with that velocity spread.

Not to mention the STD Dev? If I get a std deviation of more than 20fps I get worried. Are we missing a "." somewhere? If not your battery is a gonner.

I built a small 9V regulator and bought a 12V gelled cell to avert this problem. Used to get so frustrated when you do a bunch of critical load development, spend hours prepping cases and taking care and the data is corrupted by a flat battery.

^^^^^This

The one that came out at 1500fps Should have been drastically noticed for low or no power. That's really slow for that cartridge and would have had very low recoil.

 

[steve4102]

Hi Poper,

I am lost;

Your chrony battery must have been getting flat. How on earth is it possible to have a ES of 1228 and 1355, a change in velocity of around 40%. It is impossible to get sub 2" groups with that velocity spread.

Not to mention the STD Dev? If I get a std deviation of more than 20fps I get worried. Are we missing a "." somewhere? If not your battery is a gonner.

I built a small 9V regulator and bought a 12V gelled cell to avert this problem. Used to get so frustrated when you do a bunch of critical load development, spend hours prepping cases and taking care and the data is corrupted by a flat battery.

I was wondering the same thing!

A high of 2730fps and a low of 1501fps with MagTech primers??

A high of 2867fps and a low of 1511fps with WLR primers??

Somethin ain't right?

 

[Poper]

The battery is not low. It is less than 30 days old and is an Eveready Ultimate Lithium battery with little use. I didn't try to explain the numbers nor am I going to try. They are what the machine recorded.

Surely you read this as well?

4) Would I get similar results if I was to repeat this test?

It would be interesting to try it again with OFB. Similar results may be worth a telephone call to Shooting Chrony.

Poper

 

[USSR]

The battery is not low. It is less than 30 days old and is an Eveready Ultimate Lithium battery with little use. I didn't try to explain the numbers nor am I going to try. They are what the machine recorded.

The battery may not have failed, but there was a chronograph failure somewhere that completely invalidates the data. You simply do not get ES numbers like that with a properly functioning chronograph.

Don

 

[Poper]

The battery may not have failed, but there was a chronograph failure somewhere that completely invalidates the data. You simply do not get ES numbers like that with a properly functioning chronograph.

Don

And your solution is to not report the data? Or what?

My first reaction is to run the same test again and see if the results are repeatable. If so, and in the results are within the same range with the same primers of the same lot, then one may be closer to assuming the original data may have been valid. If the data does not repeat or if say the CCI data mirrors the previous MT or Win data, then a suspect chrono malfunction is possible.

If similar erratic data is collected in a second test, then it would be logical to try the same experiment over a different chronograph, would it not?

Poper

 

[Rule3]

Thanks for putting the time and work in and posting your results.


Extreme Spreads can be powder weight related. How was the powder dropped?. Was each load weighed? Sorry if I missed it if you explained it.

After having problems with two Chronys and returning them, I have little faith in their ability to be accurate. The would not function in the nuclear FL sunlight,
Since getting a Competition Electronics I have had no issues, JMO

 

[USSR]

Quote:
The battery may not have failed, but there was a chronograph failure somewhere that completely invalidates the data. You simply do not get ES numbers like that with a properly functioning chronograph.

Don

And your solution is to not report the data? Or what?

Exactly! Reporting data that is obviously flawed does nothing for the tester's credibility. You go back to the drawing board, figure out why your chronograph wasn't working properly, fix it and then rerun the test.

Don

 

[heavydluxe]

This isn't a peer-reviewed journal. This is someone experimenting and letting us all hop on for the ride.

Looking forward to future posts, Poper.

 

[Rule3]

This isn't a peer-reviewed journal. This is someone experimenting and letting us all hop on for the ride.

Looking forward to future posts, Poper.

Well don't "review" the other posts then You can not expect to post something and then not hear other opinions.

I appreciate the time and work going into posting such data. Done it myself. It takes time and effort and I applaud those that do it.

From the data there is something a miss, what that is, I nor anyone can say for sure. If I get data with one "wild" shot I will delete it.

Nothing I posted was meant in any way to be negative towards the OP.

 

[NCsmitty]

The battery may not have failed, but there was a chronograph failure somewhere that completely invalidates the data. You simply do not get ES numbers like that with a properly functioning chronograph.

That's pretty much the deal here. If you had a legitimate low number like you indicated, it would have been a very noticeable reduction in recoil and muzzle report for comparison. I like to be at least 15' from chronograph to the muzzle, so the muzzle blast doesn't affect the data, but I'm not saying that's what happened.
I encourage you to give it another try, as I enjoy reading information from those who take the time to do tests like this.


NCsmitty

 

[rodregier]

Muzzle blast from too-close deployment is one of the biggest sources of weird readings on an optical chronograph.

If you're serious about getting good chrono data, lot of charm running some .22LR projectiles thru first to confirm it's working well. Of course, that does imply you have access to .22LR ammunition these days.

 

[forestswin]

Poper
by chance did you write your individual chrono readings down on paper? I know the chrongraphs store the strings, but if you did, maybe some of the data can be analyzed on a spreadsheet - throwing out some bogus readings.

Geez a 30-06 with 40 rounds - how's your shoulder??

 

[Poper]

Geez a 30-06 with 40 rounds - how's your shoulder??

Actually, it was quite comfortable to shoot off sand bags.
The 53.5 grains of IMR 4350 is pretty close to a starting load for the 155 grain Berger and the Weatherby Vanguard in the walnut stock ain't no lightweight!

Muzzle blast from too-close deployment is one of the biggest sources of weird readings on an optical chronograph.

I have been thinking about this, too. I have a longer cable and I will try another 5 or 6 feet downrange just to see. A friend has suggested adding additional shade cover, too.

I'm going to run the experiment again. Same everything except a one-grain increase to the powder charge (54.5 grains) this time - still well below maximum - and the additional 5' or 6' of space between the muzzle and the chronograph.

Poper