September 5, 2018, 04:11 PM | #1 |
Senior Member
Join Date: July 8, 2013
Location: Littleton, Colorado
Posts: 1,121
|
Bench Rest CCI Primers
Is it safe to use CCI BR-2 Large Rifle primers in place of a standard CCI Large Rifle primers?
|
September 5, 2018, 04:36 PM | #2 |
Senior Member
Join Date: April 10, 2008
Location: Alaska
Posts: 7,014
|
Yes
__________________
Science and Facts are True whether you believe it or not |
September 5, 2018, 04:54 PM | #3 |
Senior Member
Join Date: July 28, 2007
Location: Ohio
Posts: 11,755
|
Really need more info.
If you are currently running some load that runs the ragged edge of the red line... then ~NO~ it is neither safe nor smart to simply insert another primer of any sort. If your load is moderate, then throwing a new primer in isn't unsafe, but it may definitely alter the performance or POI of the load.
__________________
Attention Brass rats and other reloaders: I really need .327 Federal Magnum brass, no lot size too small. Tell me what caliber you need and I'll see what I have to swap. PM me and we'll discuss. |
September 5, 2018, 06:39 PM | #4 |
Senior Member
Join Date: September 2, 2010
Location: Plainview , Long Island NY
Posts: 3,863
|
CCI BR 2 is the same primer just better quality control used for benchrest and competition ,
|
September 6, 2018, 07:06 AM | #5 |
Senior Member
Join Date: July 9, 2007
Location: Fort Pierce, Florida
Posts: 381
|
CCI BR primers are my usual primer
(I load for accuracy ) As started above they are a standard primer but they have a thicker cup and are made by The more experienced people (less variation ) (The thicker cup helps prevent slamfires in some military rifles) |
September 6, 2018, 06:31 PM | #6 |
Senior Member
Join Date: April 10, 2008
Location: Alaska
Posts: 7,014
|
I don't believe that they are thicker is correct.
At least lit says more sensitive not less. They do have a military line that probably is thicker.
__________________
Science and Facts are True whether you believe it or not |
September 6, 2018, 06:40 PM | #7 |
Senior Member
Join Date: March 1, 2009
Posts: 4,232
|
BR2's use the same cup as the 200
https://www.sksboards.com/smf/index.php?topic=56422.0 Never used a BR2 myself but in the morning I am doing a little 5 shot test with Rem, Win, CCI200, and Fed Gold Medals on a load I am working on
__________________
“How do I get to the next level?” Well, you get to the next level by being the first one on the range and the last one to leave.” – Jerry Miculek |
September 6, 2018, 09:10 PM | #8 |
Senior Member
Join Date: September 2, 2010
Location: Plainview , Long Island NY
Posts: 3,863
|
I like using what is recommended CCI large rifle or CCI BR2 you won't see a difference , the same goes for Federal primers, Now if the question was magnum or standard primers you could use them in a pinch but I wouldn't make a habit of it . I have used magnum primers with my 45ACP in a pinch and didn't see a difference .
|
September 7, 2018, 08:51 AM | #9 |
Staff
Join Date: March 4, 2005
Location: Ohio
Posts: 21,017
|
CCI military sensitivity spec (less sensitive than commercial) #34 and #41 primers do not have thicker cups. CCI told me over the phone those primers have cups and priming compound formula and quantity identical to CCI 250 and 450 magnum rifle primers, respectively. The lower sensitivity is achieved by using an anvil whose legs have a wider included angle of spread, making them a little shorter and a little less rigid than the anvils they use in the 250's and 450's. So these are really a modified commercial primer. Actual mil-spec primers go through a lot of additional lot sample testing and are a lot more expensive, therefore. The only military sensitivity spec primer I am aware of that uses a thicker cup to reduce sensitivity is the Federal GM205MAR for 5.56 (they don't make a large rifle military sensitivity spec primer). Unlike the CCI #41, it is not a magnum primer, but rather is their 205M match primer in the thicker cup.
The CCI BR primers are, as mentioned before, simply a standard primer design executed to higher QC requirements, with selected cups and anvils and the priming mix dosage introduced with an eye to higher consistency by their most experienced primer making personnel. CCI claims on their site: An independent researcher identified the use of CCI Benchrest primers as one of two factors that were the most significant contributors to tiny groups. It may be hype, but if they are genuinely more consistent it probably isn't. It's just that for reasons of how standard deviations add up, it won't be apparent unless you are trying to tighten groups of a quarter moa or less. Also, in every situation where the combination of powder and bullet are different, you can get different results. I've read recently someone saying BR primers did the worst in his experiment. There are a lot of variables here that may not be the primer's fault, though, like different seating effort messing up the handloader's use of them, or slightly lower sensitivity than, say, a Federal primer causing a mainspring that has taken a set to fail to strike with enough energy to make a less sensitive primer fire consistently. If your gun is not shooting under 1 moa, the component combination typically matters less than if you are, but as with all other rules about loading for accuracy I know of at least one published exception where groups went from 2 moa to 1 moa with one change to one component (outside neck turning of the brass) and have personally had flash hole deburring take loads of one powder from about 1.25 moa to 0.7 moa (but I could easily get that gun to shoot 0.7 moa with other powders without resorting to deburring). Until you try something in your gun, nothing is certain about it.
__________________
Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle |
September 7, 2018, 09:57 AM | #10 |
Senior Member
Join Date: April 11, 2013
Location: High up in the Rocky Moun
Posts: 665
|
According to research I did a few years ago, Remington #7 1/2 SM and 9 1/2 LR are true MilSpec.
The 7 1/2 was developed for the 5.56X45mm. This info came from the NRA.
__________________
The soldier's pack is not so heavy a burden as the prisoner's chains. Dwight Eisenhower It is very important what a man stands for. But it is far more important what a man refuses to stand for. |
September 7, 2018, 05:33 PM | #11 |
Senior Member
Join Date: September 2, 2010
Location: Plainview , Long Island NY
Posts: 3,863
|
If your looking for good reliable primers benchrest is the way to go , my pay alittle more .When quality drops and problems arise switsh to another brand . For now CCI BR2 primers are excellent primers..
|
September 7, 2018, 08:31 PM | #12 |
Senior Member
Join Date: August 26, 2016
Location: North Dakota
Posts: 1,636
|
I have used tens of thousands of cci primers. I like them in many applications. In gas guns, BR primers are a waste of money. In testing BR2's in my AR-10, and BR4's in my national match 223, I saw no appreciable difference in coefficient of variation with respect to velocity.....and no difference in reliability either.
In other rifles, I found BR4 and BR2 made very modest differences in low capacity cases like 204 ruger, 223, 243...and a virtually statistically insignificant difference (depending on your confidence interval) for larger case capacities like 270 win. So, I cant say it makes "no" difference. But I doubt anyone outside of a true bench rest competitor would really notice any improvement. Last edited by Stats Shooter; September 8, 2018 at 07:12 AM. |
September 8, 2018, 11:42 AM | #13 |
Senior Member
Join Date: February 13, 2002
Location: Canada
Posts: 12,453
|
"...They do have a military line that..." Are nothing more than magnum primers. Nothing military about 'em except the brilliant marketing. You don't need 'em for a semi-auto battle rifle either.
Never noticed any difference between a BR primer and a regular primer myself.
__________________
Spelling and grammar count! |
September 9, 2018, 07:39 PM | #14 | ||
Senior Member
Join Date: June 8, 2016
Location: Cleveland, Ohio Suburbs
Posts: 1,750
|
T. O'Heir:
Quote:
Quote:
Ron |
||
Thread Tools | Search this Thread |
|
|