Small Rifle Primer Test

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I decided to try a little test to see how much difference there is velocity wise and accuracy wise between the small rifle primers I have on hand in my 204. I have already worked up a load using RL 15, CCI BR4, W-W brass and Horn 32 gn V-max bullets. This loads shoots about 7/8" pretty consistently for 5 shots.

I just trimmed and prepped a couple or three hundred cases for the 204 and thought it might be interesting to give this a try. This is the first trim as I didn't have a trimmer pilot for it, so I got off my a$$ the other day and spun one out on the lathe and then trimmed all my once and twice fired brass. I was just going to go ahead and load the load I had worked up and thought about trying a variety of primers to see if any one is significantly better than the others. I don't believe I have seen such a test conducted here with any posted results so I thought I would give it a go.

I also chose the 204 because of the relatively small case capacity which should be more sensitive to ignition changes than say a 300 RUM or even a 308 or 30-06.

So this is what I have done;

25 loads each with 30 gns of RL 15 in W-W brass and using the 32 gn V-max seated at 2.40", using Rem 6 1/2, CCI 400, CCI BR4 and CCI 450 primers.

The Rem 6 1/2s should give me a very gentle ignition and then up to the CCI 450s which should give me the most aggressive ignition of the works, with the CCI 400s and BR4s somewhere in the middle. So my question is which, do you think will give me the most definitive answer........5, 5 shot groups of each at separate targets, obviously over time allowing the barrel to cool after each 5 rounds, or one 25 round group (of each primer) shot at the same aiming point again shooting 5 rounds and allowing to cool.

I don't have any exceptional expectations from this rifle as it is only a sporter barreled stainless 700 SPS, and I'm not sure the primer changes will make any difference at all in velocity, extreme spread or accuracy, but it will be interesting none the less to know. I bought this rifle new and have fired less than 400 rounds through it so I know it is not shot out and all is in like new condition.

Still waiting for the weather but I was bored and decided to play in my loading room, just another tidbit of information to add to the knowledge base............
 
I did the same test once in my 204 wit fed 205m, cci 450 and br4. 3 five shot groups with each. I came to the conclusion in my rifle there was no difference. all 3 had a few fliers out of the normal .5 inch groups and all 3 had at least one excellent group tat was sub .4. however you may see different results.
 
Douglas, I don't think there will be enough difference, in any part of your test, for you to say that primers make a difference.
I went for many years using any primer that fit the primer pocket of the case, even using large pistol for 45-70 and the 30-30 class of centre fire, and never noticed any difference, whatsoever.
In the survival days of the great depression the meat hunters shot moose and elk in temperatures of forty five below zero, or sometimes even colder, always using Dominion brand factory loads. They would tell you the ammunition lost some power in the cold, but if they thoroughly cleaned the action, especially the firing pin and guide, with kerosene in the fall, the cartridges always fired.
In the 1950s a family member was in the RCMP and stationed in the eastern high arctic. The government gave the RCMP cases of Dominion 30-30 ammunition to distribute to the Eskimos (OK, Inuit) for shooting their game. I happen to have an empty box of those shells, with the RCMP marks on them, and they are standard factory ammo.
Then, I got on CGN and found that great and growing numbers of people on there felt they had to use the "correct" primer, saying that certain primers "needed" a magnum primer and all powders needed a magnum primer in cold weather.
So I contacted Boomer on here, who lives on the western side James Bay, shoots in severe cold weather, and got him to do a cold weather primer test.
Here it is, lengthy, but scroll down.
This has been on the CGN before and there are people on here who firmly believe a "hotter" primer gives better results, especially in cold weather, but the test didn't show that it made any difference.
Bruce
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"So I'll start with the test parameters. What I was looking for was ignition problems, differences in average velocities, and differences in extreme spread. To ensure it would be the primers that resulted in velocity variations, I took the trouble to keep bullet and case weight to within a quarter a grain for each 5 round group. All of the cases were trimmed and chamfered, and the primer pockets were uniformed and the flash holes uniformed and de-burred. I wanted to test both ball and extruded powders, both fast and slow burning powder, in small, medium, and large capacity cartridges.

The test did not go without a few hitches. The first problem was that the Oehler P-35 didn't read the bullets fired from my SAKO .222 magnum, which was disappointing, so there is no .222 Magnum data to report. The Chronograph failed to read one of the magnum primer loads in the .30/06 and failed to read a magnum primer load in the .458. The .270 data showed lower velocities than I would have expected for a 130 gr bullet, running in the mid 2800s then the first 3 magnum round had little spread, but the last two increased the ES to 180 fps!!?? I hadn't worked up the load however, but Bruce wanted me to have the test include 60 grs of H-4831 under a 130, so that's what I put together.

Here are the results minus the .222 Magnum . . .

.270 Winchester
Ruger Hawkeye 22 inch barrel
Winchester brass
Winchester PP bullets
60.0 gr H-4831SC

CCI LR BR-2 Primers....................Remington 9.5M LR Primers
2837..........................................2841
2830..........................................2840
2833..........................................2842
2793..........................................2953
2814..........................................2772
Average 2821, ES 44...................Average 2849, ES 181


.30/30 Winchester
Winchester 94 NWT Commemorative 24"
Winchester brass
170 gr bullets, unknown make
30.0 grs IMR 3031

CCI LR BR-2 Primers....................Remington 9.5M LR Primers
2070..........................................2026
2065..........................................2052
2021..........................................2028
2044..........................................2087
2071..........................................2052
Average 2054 ES 50....................Average 2049 ES 61


.30/06 Springfield
Brno ZG-47 24" barrel
Remington brass
180 gr Sierra BT
58.0 grs H-100|V

CCI LR BR-2 Primers....................Remington 9.5M LR Primers
2775..........................................2768
2756..........................................2783
2827..........................................2773
2758..........................................2764
2727..........................................0000
Average 2768 ES 100..................Average 2772 ES 19


.375 Ultramag
Brno 602 22" barrel
Remington brass
270 gr Hornady Interlock
92.0 grs H-100V

CCI LR BR-2 Primers....................Remington 9.5M LR Primers
2948..........................................3015
2967..........................................2991
2973..........................................2976
2923..........................................2983
3012..........................................2963
Average 2964 ES 89...................Average 2986 ES 52


.458 Winchester
Winchester M-70 Express 21" barrel
Winchester brass
500 gr Matrix
76.0 grs H-335

CCI LR BR-2 Primers................... Remington 9.5M LR Primers
2059..........................................2003
2097..........................................2066
2113..........................................2067
2054..........................................2074
2091..........................................0000
Average 2082 ES 59...................Average 2052 ES 71


So that's it. Some of the readings such as the last two magnum primer velocities in the .270 make me wonder if a combination of the low morning light and the atmosphere full of ice crystals didn't produce some false readings. Perhaps that was the reason for the lack of readings with the .222 magnum, and the missing reading in the .30/06 and the .458. Anyway, its interesting stuff, and I think it shows that although I still prefer to use magnum primers, there is no practical ballistic advantage in doing so. I was really surprised by the .458 results, as the combination of ball powder, a powder charge greater than 50 grs, and extreme cold should have made magnum primers a distinct advantage over standard primers. I did not observe any hang fires in the course of this test.
 
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IIRC Barsness did a test on LR primers, he found virtually no difference in velocity but up to 10,000 psi difference in pressure, with the same loads in the same pressure barrel.
 
RL15 is not hard to ignite, so I would not expect to see much of a difference.

The challenge is to have a test that is accurate and statistically valid. You propose a big enough sample, but are not using a rail gun, which is what I prefer for this kind of test.
 
Ganderite said:
RL15 is not hard to ignite, so I would not expect to see much of a difference.

The challenge is to have a test that is accurate and statistically valid. You propose a big enough sample, but are not using a rail gun, which is what I prefer for this kind of test.[/QUOTE]


Granted Ganderite but I'm thinking ES and velocities should be somewhat informative. The accuracy level of course will be subject to my shooting ability and the draw backs of a sporter weight barrel. But on the other hand I don't hunt with a rail gun so the out come will be relevant to my rifle, given my shooting ability as the greatest variable.
I do not propose to do this with cold ammo as I wish to keep the outcome exclusively to the different ignition parameters within a normal temp range of +20 C +/- 5 deg. If I do decide to do this relatively quickly here I will keep the ammo in my truck while I shoot, with the truck running and the interior at normal temps. I did this all winter in the Yukon and then I would fetch another 5 rounds and keep them in my shirt pocket under my parka while I shot them 1 at a time. I used to do the same while shooting silhouette in the winter, never had to worry about ambient temp performance differences. Some competitors squawked about it but there was nothing in the rules that said it could not be done this way so pretty soon everyone was doing the same thing. Same performance winter or summer.......actually air density did make some minor differences out at rams and depending on the cartridge being used, some guys had to compensate for the winter air. There is significant air density changes with a 70 degree C swing in temps that we routinely saw from summer to winter.........but this is a whole 'nother topic ain't it.

Ganderite you say RL 15 is relatively easy to light, so can one assume that easy to light powders are much less sensitive to the violence and temps of the ignition? I know from using tons of Win 296 that some powders require and thrive with the most violent ignition possible and fall off very badly with cooler and less violent ignition to the point of becoming unreliable and even potentially dangerous. I also learned from diminutive powder charges in my hornet that it too was sensitive to too violent an ignition and the accuracy is measurably better with the more gentle ignition of the Rem 6 1/2 when using L'il Gun.
Click to expand...
 
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I learned to pay attention to results and to try avoid the "why". If the power or load works best with a CCi 500, so be it. That is what matters.

I notice guys shooting a bad group with a given bullet and blaming it on the twist. Not usually.
 
The shooter is by far, the greatest variable in accuracy.
So many times an excellent group will be made, but can not be repeated. Even in trips to the range, shooters will have good days and bad days. And when its a bad day they will usually blame everything, except the shooter!
I think the chronograph is far more reliable in testing for accuracy than is shooting.
 
The accuracy of the test you propose is dependent on the tools and procedures you use to produce loaded ammo. And, measuring velocity accurately.
This essentially means that bench rest quality ammo with a single digit ES capability.
Once a base line is established, with a statistically large enough sample the testing can begin.

I do not have any preference to primer brand due to the energy they produce, but rather cup thickness and consistency.
Velocity is regulated by powder charge to assure OCW/OBT which both aid in consistency and accuracy.

Should be a good test. ��
 
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