Benchrest Primers VS CCI

[Remshooter]

I normally use the CCI primers but thought I would try some CCI BR primers just to see if there was much difference. Are
they hotter, more consistent or all of the above??

 

[fullersson]

In my experience the BR4's are more consistant than the 450's. I get better groups and less flyers with the BR4's.

 

[necchi]

From what I understand the BR are off the same line, only "hand selected" by a senior/more experianced worker,

 

[limbic]

Isn't that also the difference between 205 and 205M? I'm a big fan of the br4. I don't think they are hotter.

 

[K22]

Federal 205M match primers are not hotter than standard 205 primers, the same is true for CCI standard primers 400 and match primers BR4. Reference: Lyman Reloading Guide, 47th edition.

 

[dcali]

I've never been able to tell the difference.

 

[Laurie]

I've got to disagree with the comments that there is no difference between CCI-450 and BR4 types. I'd always believed the latter was simply a selected batch of the former too, but my .223 Rem F/TR rifle using 90gn Bergers says otherwise. Comparing the two from lots purchased at the same time, the BR4 consistently gave around 40 fps higher MVs with my then match load's charge of Reloder 15, a much larger MV spread, and doubled 100yd group sizes. Reducing the charge weight slightly to get it back to that produced by the 450s didn't reduce the ES or group sizes, so I could only deduce the two primers weren't behaving the same way and the BR4 is likely 'too hot' for the 24.5-25.2gn charges I'm using here.

Comparing them with other powders in the cartridge and 90gn Bergers - N540, N550, and IMR-4007SSC confirmed the BR4s gave consistently poorer results than the CCI-450 throughout, so it wasn't a one-off Reloder 15 issue.

This may be simply a manufacturing lot issue of course and buying the two types today would reverse those results. It's not a problem for me as I have plenty of this batch of 450s and the BR4s work fine in Lapua 'Palma' small primer .308W brass and 6BR.

It does show that when you work a load up for a specific purpose that an apparently unimportant component change can undo all your load development work. Nowadays, I recheck my match loads every time I start a new lot of primers or powder.

Laurie,
York, England

 

[limbic]

I shot my competition load today with 205m and br4. Avg fps was only 1 fps difference and es/sd were about the same. 21/8. 6 shot groups.

 

[K22]

Laurie,

CCI 450 primers are MAGNUM primers and ARE hotter than CCI Benchrest primers, BR4. The only difference between CCI 400 and BR4 is that the latter is supposedly more consistant and thus promoted for "Benchrest" use.

 

[CatShooter]

Laurie,

... The only difference between CCI 400 and BR4 is that the latter is supposedly more consistent and thus promoted for "Benchrest" use.

The biggest difference between the 400 and the BR-4 is that the 400 uses a 20 thou cup, and the BR-4 uses a 25 thou cup - that means that the 400 will crater long before the BR-4. I left the 400 because of that reason.

Meow

 

[6BRinNZ]

Remshooter - links to primer info

http://www.jamescalhoon.com/primers_and_pressure.php

CCI BR has thicker cup and slightly wider dimension

Also German Salazar has performed primer flash tests (BR4 plus other brands)

http://riflemansjournal.blogspot.com/2009/06/primers-small-rifle-primer-study.html

CCI site

http://www.cci-ammunition.com/products/primers/default.aspx

Having a quick read for each primer type - the suggestion is that magnum primers are 23% hotter, BRs have a little more effort in selecting the materials and 400s have a wider strike region for off center pins.

This site suggests for 6BR case and 105 grn projectiles CCI450 with varget is showing better numbers...basically all of this means try and if you like buy