6.5 CREEDMOOR Brass. Small or large primer

[GR5150]

Hey y’all. I have a question that I know the folks on here will have the knowledge I seek. I just ordered 50 Pieces of brass from Peterson with Large rifle primer pockets. I know a few guys that shoot the small primer brass. What I would like to know what the advantages of each are. I’ve been told that the small rifle primers yield lower ES/SD. Do you have to use the small magnum primers. Is there a substantial difference in velocity between using small/large primers. I want to thank everyone that responds in advance. Gary

 

[rardoin]

I've shot both large and small primer Lapua brass and I have found great groups and mediocre groups with both; either case can yield very good precision. I have some loads that liked magnum primers and others that did not in the small primer brass. I have not seen a significant difference in velocity spread on given loads between the two. I would expect greater primer pocket life in the small primer brass if you are hammering them with higher pressure loads...ie. upper 2800's or more with a 140gr+. Shoot your large primer brass since you already have it it and test small primer when those give up the necks or primer pockets.

 

[GR5150]

Im planning on developing a load with the 123 ELDMs and H4350. I use CCI Standard LR primers. I had a good load with the 120 ELDs with Varget. My rifle is a R700 AAC-SD with a 22 in barrel. 130s is as heavy as I plan on going with it. Thanks for the reply. Gary

 

[Charwell]

I have a 20 inch 6.5 creedmoor. Mine liked varget with the 123. H4350 for the 130. I can put 40.5 grains h4350, in hornady brass with 210m, or lapua brass with cci450, with 130 accubond or 130 Berger and not touch the scope. If I use 205m in the lapua brass , it looks like 00buck. I don't have any velocity data .edit , I should add 39.5 grains varget and 123amax , hornady brass , 210m has same poi.

 

[wboggs]

I have a 20 inch 6.5 creedmoor. Mine liked varget with the 123. H4350 for the 130. I can put 40.5 grains h4350, in hornady brass with 210m, or lapua brass with cci450, with 130 accubond or 130 Berger and not touch the scope. If I use 205m in the lapua brass , it looks like 00buck. I don't have any velocity data .

I used identical loads in a 260 rem with large and small primers. There was about a 50fps increase with the large primers and about half the sd with the small primers.

 

[mgunderson]

Powder selection and external temperature need to be considered with small primers. Had good results with 123-130 class bullets, H4350, and LRP brass.

It is common to need to increase the powder charge a few tenths to maintain velocity when switching to small primer brass.

 

[JigStick]

Longer brass life and smaller ES with the small primers

 

[MagnumManiac]

I use SR Lapua brass in my 22-250AI & 6.5x47, each produce smaller SD & ES compared to LR Winchester/S&B brass.

Using my pressure trace II, I found that the SR brass handles hotter loads without expanding the pockets prematurely.
Brass lasts a looooooong time also.
I wish more companies would come out with SR brass in different cartridges than already out there.
It definitely has it’s advantages.

Cheers.

 

[Hengehold]

Hey y’all. I have a question that I know the folks on here will have the knowledge I seek. I just ordered 50 Pieces of brass from Peterson with Large rifle primer pockets. I know a few guys that shoot the small primer brass. What I would like to know what the advantages of each are. I’ve been told that the small rifle primers yield lower ES/SD. Do you have to use the small magnum primers. Is there a substantial difference in velocity between using small/large primers. I want to thank everyone that responds in advance. Gary

I think that a common observation is that it takes a little more powder (.5 gr?) to achieve the same velocity when changing from LP to SP. For example:
LP=3000fps with 45.0 gr of powder
SP=3000fps with 45.5 gr of powder

This may not be an issue for you unless the case/bullet/powder combo is already hitting the accuracy node with a full case of powder in the LP configuration. In this instance, with a SP case you may need to add that .5 gr of powder to stay in the accuracy node which could result in a compressed load. Bottom line, if you have room in the case for more powder then try the SP.

From a performance perspective, I shot with the US Palma team in 2011 and we used SP palma brass exclusively. It performed very well but I can not say that I could notice an improvement on paper from the one time use of virgin brass. That is my perspective as a prone/sling shooter. I never reloaded that brass so can not speak to the benefits of brass life.

great thread. good luck.

-Trevor

 

[nakneker]

You made a good choice on getting yourself some Peterson Brass, you’ll be happy with that. The thing I like about the SP brass is the longevity. I think it handles pressure better and you get a few more loads out of the brass.

 

[waterdog]

I use Lapua 6.5 Creedmoor brass, CCI-450 primers, R-16 powder and Berger 130 grain hybrids. I am a believer in Lapua brass having been in the benchrest game at 600 and 1000 yards, although I don’t compete anymore.
brass seems to last a very long time.