Need small rifle primer advice .

[quigley257]

Nearly all of the PRS shooters who use SRPs utilize the 450s so it's a no-brainer from that standpoint.

 

[Hugnot]

Some think, and they are probably correct, that the best accuracy & minimum variance is obtained with the minimum but adequate primer energy. Thus the 6.5X47 Lapua, .308W (SRP) & others like 6.5 Creedmoor (SRP). I have never seen a 6.5X47 Lapua with a LRP, but I might have not looked long enough. I hear 300 meter target shooting is real tough & attracts fierce competition . The X ring is about the size of a baseball inside a huge black circle. Standing, kneeling, & prone positions. My old body could not do the kneeling. I would guess ammo is loaded with 140 grain bullets & VN 540 or VN550 powder that is easier to ignite than ball powders like StaBall & Hunter. It gets cold in northern Europe.

I have many more SRP than LRP & I have been able to sustain my supply of CCI 41's at local gun stores, like Sport's Ware House & Scheels. I can buy SRP one fired 6.5 CM brass & neck it down or leave it as is for 6mm & 6.5 CM & keep on shooting. CCI 41's have worked out well with AA4350 and simlar extruded powders but 40 grain plus charges of Staball 65 & RS Hunter have not been good. The CCI 41's are intended for "For 5.56 mm Ammunition Small Rifle Military Primers", white box. The primers that I have measured have less anvil exposed. The CCI 41's have given great results with extruded powders, 40 grains plus & small charges of ball powders. Be sure your firing pin is snappy.

After reading:

https://arxiv.org/ftp/arxiv/papers/1203/1203.2701.pdf

I was able to buy 1000 Rem 7 1/2's and the Staball & Hunter groups tightened up. The Rem 7 1/2 is a real frisky little primer & sets of ball powders well.

Gotta adapt to keep shooting!

 

[Rosebud]

I was in same boat couple of years ago. I bought SRP Lapua Creedmoor brass, used 450s. Worked better than I would ever have expected. Just as accurate as my LRP loads, and just as fast. The reasoning behind the SRP is longer case life. More brass around the primer pocket. I've got some on their high double digits for reloads, pockets as tight as new. I've heard that there could be issues in extreme cold. But no data to back up said claim.

 

[Sasman]

Well now you have me a bit confused, which at my age is somewhat difficult to do. I have been loading .308 since about 1970 and all of the brass I have come across for the .308 uses Large Rifle Primers. I have never run across any .308 cases with Small Rifle Primers. First of all, where did you find them? Secondly why outside of primer availability would you want to use small primers in a cartridge designed for large primers. There has to be a big difference in flame propagation between the two thus burn rate and pressure differences which would affect bullet velocity. Over the years I have found that using Magnum primers in virtually everything I load works well. Of course I work up the loads from scratch, using the minimum velocity from the loading chart and have not noticed any real changes in velocity or pressures even when working at the top end of the loading chart. I have had people tell me I am crazy, and to be honest probably all of us are, but this crazy old lady is not afraid to experiment but does do it carefully. In closing, what advantage is there to using small rifle primers in a cartridge designed for large rifle outside of primer availability which while yet is somewhat of a challenge they are pretty much available these days, Oh, yeah I forgot.Magnum primers are pretty well available, not so much any of the specialty type primers. View attachment 386479

Yeah large rifle primers right now here in Canada , are about as easy to find as Hens teeth . Small rifle primers are still available but i figured i would try whatever i could find as this shortage is "supposed " to continue for the next 2 years !!! To make sure i could continue shooting , i had to invest in new 308 small primer brass and some once fired 6.5 Creedmoor small primer brass . I was asking for advise using what i had for primers , cci400's, BR4's and 450 Magnum primers for each of those rounds .

 

[QuietTexan]

308 Palma brass is for 1000 yard use, some of the logic explained to me is the case head has more brass in it and the primer can take more pressure since that particular sport is limited to one case design where SRP vs LRP is relevant (ain't no LRP 223 Rem that I've ever seen ).

No idea if it's true or not, or if all the debate over brisance and flash hole size yada yada yada truly matters in the ES/SD vs tune inside 1k yards arguments, but I can say CCI-450s are hot enough to light off 6.5 CM and 308 Win reliably, you can tune loads to small metrics with them, I use them with confidence year round (yes, it does get below freezing in Texas during hunting season - 0* is 0* everywhere y'all and it'll freeze anything just the same), and I actually prefer them right now because like you said.... they're available! Run them and keep shooting!