Which Starline brass for the 6.5 Creedmoor?

[jski]

Starline offers 2 different cases for the 6.5 Creedmoor, one with large rifle primer pockets, the other with small rifle primer pockets.

The website lists the advantages of the small rifle primers. Does anyone have experience with this?

SR 6.5 CM (Small Rifle primer)

Small Primer 6.5 Creedmoor
1.908 - 1.912 O.A.L.
This is our Small Rifle Primer version of the 6.5 Creedmoor. The 6.5 Creedmoor was designed as a target caliber in 2007 by Hornady but has become an extremely popular hunting caliber as well. While it isn't as long as some of the other 6.5 caliber short action calibers, such as the .260 Remington, the Creedmoor utilizes a 30° shoulder and very little body taper to help it achieve similar ballistics. The shorter length also gives it more versatility as far as bullet seating depth is concerned. Almost every major rifle manufacturer offers either a bolt-action rifle or a modern sporting rifle in 6.5 Creedmoor caliber due to its versatility and inherent accuracy.

Our SR6.5CM brass uses a Small Rifle Primer. Many target shooters prefer the Small Primer for the increased consistency and accuracy. While other small pocket manufacturers use a smaller than standard flash hole, Starline uses our standard .080" flash hole, as we feel that it gives better ignition with some of the slower powders and in cooler conditions* (and you won't be breaking off decapping pins either!)The Small Primer version also maintains primer pocket size much better than the large primer version under higher pressures. For our Large Primer version please see our 6.5 Creedmoor case.

*As with all types of cases this large with small primer pockets, it will require care in powder and primer selection in cooler temperatures to prevent hang fires. Single-based propellents are generally easier to ignite and a quality primer such as the Remington 7 1/2 BR are recommended.

 

[farmerboy78]

I shooting buddy of mine uses the starlings srp and I have used .308 lapua Palma with srp... the small pocket seems to handle pressure better, but be sure your decapper will work with it.

 

[rayatphonix]

Starline uses the same size flash hole in both the large and small primer versions of Creedmoor and .308 brass. That should eliminate decapper pin problems. I’ve got 500 cases I bought on sale. I’m cycling through the rest of my Hornady brass before I give it a try. I’ve heard good things.

 

[Blue68f100]

Yes, to the Lapula SP having a smaller flash hole. I prefer the SP over the LP if I have the option. I believe it holds up to pressure better since it has more meat around the pocket. I received a bad batch/lot of Lapula brass that had a bunch of defects that only showed up after the first cleaning. I returned the whole 200 and bought Starline's SP brass. You have to do more prep work to the Starline but I'm finding it very uniform and consistent.

 

[jski]

...
I returned the whole 200 and bought Starline's SP brass. You have to do more prep work to the Starline but I'm finding it very uniform and consistent.

Care to elaborate on “more prep work”?

 

[Blue68f100]

All related to the primer pocket. The flash holes are punched so you need to remove the flashing on the inside of the brass. The depth is good on all that I've checked. Starline recommends sizing the brass prior to loading, to remove dings in necks from handling. The brass length was at trim length, personally I prefer them to be SAAMI spec which is normally 0.010" longer, no bigie.

 

[rayatphonix]

Blue, how do you go about cleaning up burrs on the inside of the case? Or did I misunderstand and it's the inside of the primer pocket that needs to be cleaned?

 

[Blue68f100]

With tools like these flash hole deburring. https://www.midwayusa.com/product/125945/redding-flash-hole-deburring-tool-with-30-caliber-pilot

When the hole is punched it will have a flashing on one side if not all the way around. This impacts the consistency of the powder igniting.

Far as I know Lapula is the only mfg machining the flash holes vs punching them out. So the cleaning needs to be done to all punched flashed holes if your looking for the max accuracy.

 

[jski]

Guys, we haven't really addressed my original question: small v. large rifle primers.

Our 6.5 Creedmoor brass uses a Large Rifle Primer. This is the standard for this round and it is what many prefer due to its reliable ignition no matter what temperature you are shooting in or the burn rate of your powder.

Our SR 6.5 Creedmoor brass uses a Small Rifle Primer. Many target shooters prefer the Small Primer for the increased consistency and accuracy. While other small pocket manufacturers use a smaller than standard flash hole, Starline uses our standard .080" flash hole, as we feel that it gives better ignition with some of the slower powders and in cooler conditions* (and you won't be breaking off decapping pins either!)The Small Primer version also maintains primer pocket size much better than the large primer version under higher pressures. For our Large Primer version please see our 6.5 Creedmoor case.

*As with all types of cases this large with small primer pockets, it will require care in powder and primer selection in cooler temperatures to prevent hang fires. Single-based propellents are generally easier to ignite and a quality primer such as the Remington 7 1/2 BR are recommended.

 

[rayatphonix]

Fair enough. In theory small primer brass for the Creedmoor should provide greater strength of the primer pockets because there is more material. This should result in longer brass life if you anneal the necks. Without annealing the neck is likely to work harden before the primer pocket expands too much to securely hold the primer. Additionally, some people feel the small primer pockets allow for greater pressures thanks to the additional strength. Higher pressure often means higher velocity. Finally, some say the small primer is more consistent than the large primer and therefore you’ll have less deviation from shot to shot.

From a negative standpoint some are of the opinion that small primers may have difficulty consistently igniting some powders, especially in cooler weather. I found a site that studied this and doesn’t believe that should be a problem. As Starline uses .080” holes in their small primer brass, I think it is a non-issue. Large primer brass uses an .080” flash hole, small primer brass typically uses a smaller flash hole. Blue recommended removing the burr on the flash hole and I think that’s prudent in any case.

I am going to start using small primer brass on both my Creedmoor and .308 rifles, mainly because of the longer brass life. I anneal, so case hardening is a non-issue and I believe the positives outnumber the negatives. I’ll begin loading some .308 this coming weekend but it will likely be a while before I try the Creedmoor.

 

[rayatphonix]

BTW, what I’ve written is mostly what’s on Starline’s site. I researched the claims on the web and opinions seem consistent. I’ll say again that if I didn’t anneal, I wouldn’t have changed.

 

[Varminterror]

Small rifle, no question.

 

[jski]

This is from Lapua's website on their 6.5 Creedmoor brass:

6.5 Creedmoor brass with small rifle primer
Made with Lapua’s typical dedication to precision, our new 6.5 Creedmoor case has been refined just a bit, to make it an even better performer. We’ve opted for the small rifle primer, which normally produces an optimized ignition and better accuracy than large primers in mid-sized cartridges like the Creedmoor.

We’ve also incorporated our smaller diameter flash hole (1.5mm, rather than the industry standard 2.0mm), which has proven to provide enhanced accuracy, and is used in a number of our other accuracy oriented cases. In this respect, the new 6.5 Creedmoor joins the ranks of our other dedicated accuracy cartridges such as the .220 Russian (6mm PPC), the 6mm BR Norma, the 6.5x47 Lapua and the .308 Win. Palma cases.

And naturally, the 6.5 Creedmoor is made with our well known Passion for Precision. Lapua ammunition is manufactured with strictest control over the metallurgy, the forming and drawing processes and precise annealing, all performed under the watchful eyes of our production experts. For you, the handloader, that means the durability for which our cases are famous, combined with consistency and long life. Already proven in shooting competitions, we predict that the 6.5 Creedmoor will be a force to be reckoned with for many years to come.

Evidently, they subscribe to the small rifle primer theory. Unlike Starline, they don't also offer a large rifle primer case.

 

[joneb]

Some powders may perform better with a large rifle primer

 

[ArchAngelCD]

There is an article on this in the May 2018 Shooting Times.

Lane Pearce did a side by side test of Starline 6.5mm Creedmoor brass with both large and small rifle primers. He concluded the large rifle primed brass was more reliable especially when double based powders are used. Cold weather also showed a variation in complete powder ignition favoring the LRP based brass. He said its possible to produce a hangfire or squib with the small primer brass.

It's worth a read if you are loading for the 6.5mm Creedmoor.

 

[Varminterror]

Some powders may perform better with a large rifle primer

Which top performing powder in 6.5 Creedmoor consistently and reliably does better (which I assume means “yields more precise loads at max or near max velocity”) than H4350 and small primers?