Load Compatibility w Primer Size?

[257Roberts]

With these uncharted waters of components scarceness, one needs to consider all options, one of those is swapping to brass with small primer pockets. Currently, 223 Rem is the only thing I load with small primers and and thus my supply of small primers is far better than large.

I understand the principles in why small primers are used in some of these match loadings, but my question is, are large rifle recipes somewhat compatible if swapping down primer size, or does one need to start from scratch?

 

[Bc'z]

Ignition source is vital to a loads tune.
Abbreviated charge weight test is in order.

 

[RegionRat]

Yes with the above warning to check your work-up.

Small Primer swapped into a Large Primer load isn’t something I have done a lot of, but with this kind of choice coming along in some popular topics like 308 based calibers I have done it. I have not been tempted to explore ball powders or cold weather. Those are tests that will have to wait for when and if things get back to normal. Those are the less obvious questions in my own mind.

I didn’t have trouble with Varget for a typical Palma load, so take that with a grain of salt. The difference for me was in the noise level that I would expect for new brass versus cycled brass with all other things being equal.

 

[MagnumManiac]

I have tested both SR and LR primer brass side by side in 22-250 brass and 6.5x47.
The accuracy loads always vary and the SR primed brass hits pressure later in both cases.
The advantage for SR primed brass on a .473” bolt face is twofold, the start pressure is more uniform and the brass is tougher and able to withstand continued use at max pressure for longer.
If you have brass with SMALL flash hole, DO NOT open it up, it is this that makes the ES so uniform and wide nodes. Modify your decapping pin.

Cheers.

 

[Ned Ludd]

Shooters have been using SRPs in .308 Win cases with great success for a long time (i.e. Palma brass). The .308 Win case has slightly under double the internal volume of a .223 Rem case, so you can use that as an additional data point if you're thinking about some other larger cartridge. As has been mentioned, primer brisance, temperature, and powder selection (i.e. single base versus double base) can all affect ignition, and thus are important considerations in the context of SRP versus LRP.

 

[CA_Shooter]

I had the same conundrum as you. Small primers was all I had, so I had to switch up my brass to small primers.

I also found that I ended up getting pressure signs on the primers at mid range powder charges on the first firing. After brass growth I did not get pressure signs at even higher charges. Just something to look out for.

 

[JAlfred]

How have SR primed cases faired with volumes at or greater than 308 Win?

With SR primed cases greater than 223 volume and less than or equal to 6.5 Creedmoor, have magnum primers shown an advantage?

Not trying to stir up a mess, I just have a good supply of SR primers and not much else...

 

[Laurie]

With larger size cases and charges, small primers often give slightly reduced performance compared to LP equivalent brass from the same maker and with the same internal capacity. I've seen up to 1.5gn difference in 308 Win to produce same MVs.

As @Ned Ludd says, SP versions of the larger capacity cartridges are more powder make/grade and ambient temperature sensitive than LP versions. I found Lapua SP 308 'Palma' brass failed to ignite Hodgdon CFE-223 with a near 100% hangfire rate and the occasional complete misfire. (It's not necessarily an extruded v ball powder issue. Palma brass worked very well indeed in a test with the much older Hodgdon H414 ball powder, and some extrudeds work better with LP than SP too.)

 

[The boogalorian]

Where are you located? I’ll bet that you could find someone local that is willing to swap some Lrp’s for some srp’s.