Primers: small -vs- large. Fact -vs- theory.

[dcali]

If there is an accuracy difference, it is slight, and obviously has something to do with optimizing ignition. As such, I'd expect to see differences with different calibers, powders, bullet weights etc. It's too broad a topic to answer definitively.

What is indisputable and easily verified is that small primer brass is stronger and will tolerate higher pressures, which will give you a little more flexibility in your tune. Small rifle brass will tolerate loads that toast large primer brass in one firing.

 

[Laurie]

I am not sure I have 'facts', but I have data .

I have not lost one piece of this brass to loose primer pockets, but am starting to get case head separations now. Note that this brass has seen two different barrels, with slightly different headspace in each barrel.

Your mileage may vary, but I am impressed with the life of the brass, the consistency of the velocity I can readily attain, and the low cost of 'doing business' using this brass.

Frank

That's very interesting re case life. I've wondered for some time what can be expected with annealing. When the Palma case first appeared, people often junked them after five or six firings, not because of any problems or an incipient failure becoming visible, rather a 'feeling' that the necks and shoulders must be getting work hardened and starting to produce inconsistent neck-tension on the bullet. Once affordable annealing machines arrived, most serious L-R competitors annealed their brass instead and kept it going much longer into double figures, but to date you're the first person I've come across who says "I got xx loadings out of mine before they started to fail." ............ and 24 is mighty good! My FTR load was 3,050 fps for the 155.5 Berger over IMR-8208 XBR, now dropped to 3,027 fps due to chamber throat wear - a real weakling loading by today's FTR standards - so I'll likely see something similar, although it'd need another two barrels or so to get to 20+ loadings with the number of these cases I have in use. It'll be interesting to see what the guys with the very hot loadings eventually get. So far, the feedback I'm getting is that they're up to 10-15 loadings and primer pockets / case-heads aren't expanding noticeably.

 

[Ned Ludd]

If one does a search, it will show Lapua went through exhaustive testing with primer size on this case....IIRC one of the reasons it took so long to get the 6.5 x 47 into production. IMHO, Lapua has their act together when it comes to case design.

I agree. I only wish they would consider adding .223 Rem cases with the smaller flash hole to their lineup.

 

[AckleymanII]

I agree. I only wish they would consider adding .223 Rem cases with the smaller flash hole to their lineup.

I am working with a 6 XC, brass made from 308 palma brass. 12 pieces of brass has been fired 35 times, annealed regularly, primer pockets are fine. Best load so far is 39.5g of H4350, and huge improvement in accuracy with a 7 1/2 vs a cci 450, velocity is 3070 fps, bug holes. Bullets are 107g Sierra's. Now with Lapua 308 brass with the large primers, I am getting 3170 out of the 107's with CCI 200's, excellent accuracy also. I started noticing very fine Fire Cracking for 10"+ with the bore scope within 300 rounds of shooting R#17, this powder must have battery acid in it. This is an X caliber barrel that is 31" long, and it is a hummer.

 

[1911nut]

My experience related to the original question.

I reloaded for a 219 wasp bench gun using large primer brass formed from zipper and winchester 30-30 brass.
I tested 5 different target type bullets for this cartridge using powders that worked in this cartridge in it's heyday.
3031, 4064 and 4320. I got lots of 5 shot groups @ 100 yds in the 2's and 3's.

Then I found some 30 American small primer brass and had it formed for my gun.
I was interested in this because I've come across the question about how would the 219 Wasp shoot if it had a small primer case? in several gun books and even on this forum.

Using the 30 American cases I easily found a load that shoots tighter than large primer cases - all cases were neck turned and neck sized.

With Remington 7 1/2 primers the gun has shot several groups in the low 2's and high 1's.

check this out:

http://forum.accurateshooter.com/threads/219-donaldson-wasp-with-a-small-primer.3906842/

it's not NASA research but I'm tickled.

 

[TAJ45]

That's very interesting re case life. I've wondered for some time what can be expected with annealing. When the Palma case first appeared, people often junked them after five or six firings, not because of any problems or an incipient failure becoming visible, rather a 'feeling' that the necks and shoulders must be getting work hardened and starting to produce inconsistent neck-tension on the bullet. Once affordable annealing machines arrived, most serious L-R competitors annealed their brass instead and kept it going much longer into double figures, but to date you're the first person I've come across who says "I got xx loadings out of mine before they started to fail." ............ and 24 is mighty good! My FTR load was 3,050 fps for the 155.5 Berger over IMR-8208 XBR, now dropped to 3,027 fps due to chamber throat wear - a real weakling loading by today's FTR standards - so I'll likely see something similar, although it'd need another two barrels or so to get to 20+ loadings with the number of these cases I have in use. It'll be interesting to see what the guys with the very hot loadings eventually get. So far, the feedback I'm getting is that they're up to 10-15 loadings and primer pockets / case-heads aren't expanding noticeably.

I am working with a 6 XC, brass made from 308 palma brass. 12 pieces of brass has been fired 35 times, annealed regularly, primer pockets are fine. Best load so far is 39.5g of H4350, and huge improvement in accuracy with a 7 1/2 vs a cci 450, velocity is 3070 fps, bug holes.

The above is, obviously, 35 firings on ea case, bullets iirc were 105 AMax and 107 Sierras. Both mentioned primers used.

 

[Doug Beach]

I am not sure I have 'facts', but I have data .

I have 200 pieces of Lapua 308 Palma brass that are on their 24th firing at Palma velocities/pressures (155 class bullets at ~3040 fps). I have annealed the neck/shoulder several times over those 24 firings. I chronographed a load in that brass last week, and got an average velocity of 3041, Hi velocity of 3046, low velocity of 3039 an Extreme spread of 7 fps, and a standard deviation of 2.4. The load is Tula primers under a healthy dose of H4895 with Berger 155.5 Fullbores.

I have not lost one piece of this brass to loose primer pockets, but am starting to get case head separations now. Note that this brass has seen two different barrels, with slightly different headspace in each barrel.

Your mileage may vary, but I am impressed with the life of the brass, the consistency of the velocity I can readily attain, and the low cost of 'doing business' using this brass.

Accuracy differences? Probably none that I can take advantage of, and given a load that is in 'tune' with the rifle for each type of brass, probably non-existent.

Just another data point.

Frank

Which Tula primer, exactly?

 

[wildfowler]

The other main changes are that the Palma case usually needs a slightly heavier charge than the LRP type to get the same MV, around a half grain in charges around the 45-47gn level, and that cold weather performance / reliability can be degraded the exact temperature at which undesirable effects kick in being related to the powder type and how easily it ignites. I found that some otherwise untemperamental grades started to see increased ES, groups and reduced MVs at anything below 5-deg C / 40F. Recently I got a load of hangfires and two complete misfires out of a box of 50 trial loads with Hodgdon CFE 223 in around 13-deg C ambient temperatures, on or a bit above 50F. So, certain ball powders are apparently a bad idea in this version of 308 in at least cool conditions.

Which SR primer were you using when testing this?

My go to 165 grain hunting load is 47.5 grains of CFE with a Remington 7 1/2 primer, using Palma brass.

Being in MS and the fact that I'm not likely to be out hunting with a rifle in temps below 40, I've not encountered any issues with my load. But the temp issue does cross my mind and I'm curious if you ever tested the 7 1/2 primer.

I chose the 7 1/2 primer based on the out of print German Salazar article. I seem to recall him saying they were as "hot" as large rifle primers.

Thanks.

 

[Laurie]

That was with the Italian Fiocchi SR. (CFE in standard Lapua brass with the Fiocchi LR model performed very well.)

This is not a mild primer. I carried out a 14 X SR / SRM / SR-BR primer test last autumn using a Viht N150 load in Palma 308 brass. (To be published later this year when I fit in a 15th primer model.) Out of the 14 primers tested, the Fiocchi SR produced the 4th highest average MV (and the 4th lowest SD).

To put that into context, the top half dozen so far as MV went with the N150 load were:

1st = Fed 205 .................. 2,827 fps
1st = Rem 71/2BR ............ 2,827
3rd Winchester WSR ......... 2,825
4th Fiocchi ....................... 2,823
5th CCI-BR4 .................... 2,822
6th Fed 205M ................... 2,820

in a list which goes down to 2,809 fps. (A much smaller MV range than when I ran the same test with LR Brass and primers.)

When I was shooting, I knew something funny was happening as I kept hearing / feeling what sounded like a 'rattle' and I kept checking the rifle and finding nothing amiss. I eventually realised there was a slight delay between the striker falling which I could hear / feel and the resulting ignition. Without electronic muffs that increase background sounds, I likely wouldn't have noticed what was happening.

One cartridge each in two batches (with different weight bullets) provided a complete misfire. When I pulled them, both primers had ignited, but there was no trace of any burn in the powder charge, all of the little balls looking in mint condition, although I dumped those charges anyway as a precaution.

There were other 'odd' effects. Twice in a considerable range of batches with increasing charge weights, MVs took a large hike after growing relatively slowly. I've seen this happen before once in a range with some powders as they get into their optimum pressure working ranges, but twice is unique as far I can recall.

 

[Berger.Fan222]

I am very familiar with ignition delays and recognize the sound immediately. I've seen it mostly with weaker primers and ball powders, but once with non-magnum primers and an extruded (cylinder powder) in .300 Win Mag.

The Palma case has worked very well with Fed 205M and CCI BR4 primers using Varget and H4895. If I had to shoot a ball powder in that case, I'd consider a magnum primer, or I would just use a case with large primer pockets.

 

[JohnKielly]

The Palma case has worked very well with Fed 205M and CCI BR4 primers using Varget and H4895.

I've had no issues with VV N550 & BR4s either, but I've found it to be relatively manageable for a double based powder.

 

[Laurie]

The original spec for the Palma case is to always use a magnum / BR primer. The tets by the US Palma teams showed that make / model had relatively little effect with the 155gn SMK and H. VarGet, just the type. My usual comp choice is the CCI-BR4. Here the case was used solely as a repository for side by side tests in a rifle with known characteristics and using a very easily ignited and reliable propellant, Viht N150.

In point of fact, the tests showed up far less difference between SR primers than expected and much less difference than was found in a previous similar test programme with standard brass and LR / LRM primers. However, part of the test was also to see how much difference was seen in primer cup strength given the thinner cups in standard SR models, and also variations in brass spec / strength between different makes and models. As expected this showed up in some models, and the test had to be abandoned for one make after three or four rounds due to their blanking. I then went on to use a selection of 'good performers' with N150 in my usual IMR-8208 XBR / 155.5 match load to see how they stood up to full, but not 'super-hot' pressures. One standard primer performed brilliantly, so much so that on ballistics / groups alone I would have switched to it from BR4s, but was sadly 'too soft', coming out of the chamber completely flattened despite a 0.001" headspace setting, and just on the verge of failing.

I have occasionally used ball powders before in Palma brass, notably H414 with a heavy bullet alongside matching loads in standard brass with an LR match primer, and deliberately tried in quite cold weather, only a degree or two above freezing. In this case, the small primer brass / primer performed very well, and most unusually and surprisingly actually generated higher MVs than the LRP case for the same charge weights as well as producing smaller ES/SD values.

So, all I say here is that some small primers may generate ignition problems with some ball powders in some temperature levels - frankly as expected. CFE223, which I regard as an impressive performer, may be a bit harder to ignite than other ball powders as a result of the anti-coppering treatment, or it may just be down to aggregate factors working one way. Certainly as expected, Palma cases are tending towards marginal reliability with such combinations.

 

[Stumpy1]

Which Tula primer, exactly?

Doug,

I have been using the Tula/Wolf small rifle magnum primers -same as I use for service rifle. I have had no ignition issues in cold temps with the H4895 or with IMR4064 down into the teens for temperature (I shoot a monthly winter fun match in the off season).

Hope this helps,

Frank