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View Full Version : Is the CCI BR4 primer an upgrade from Rem 7 1/2?


jepp2
August 11, 2011, 12:50 PM
I have been using the Remington 7 1/2 bench rest primer for my accuracy loads. Anyone have any experience with the CCI BR4 bench rest primer and if you found better consistency with the CCI primer?

Looks like the cost for the CCI is about 50% higher than the Remington, so I just was curious if the additional cost seemed justified.

Unclenick
August 11, 2011, 03:00 PM
CAUTION: The following post includes a load determination method not published for any cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.


Wow. Looks like CCI and Federal have both decided the market will bear shortage level prices for their BR and match products.

My answer would be they are not worth that much more in most guns most of the time. Benchrest shooters have found the key is using the mildest primer you can get so the powder has more control over final pressure and the primer has less. That way, whether the primer has match consistency or not becomes less significant to the final result.

For that reason the KVB standard primers (Tula and Wolf, at $20-$24 per 1000) have been getting kudos and favorable reviews among benchrest shooters. They can be harder to seat, but work well when you have that figured out (I run even non-crimped primer pockets through my Dillon swager to prevent hard seating). The caveat in benchrest loads is you need a load with good case fill for this to work out. If your load has a lot of empty space it may need a magnum primer to help pressurize the empty space, at which point the match magnums may be your best bet, despite the cost. Powder Valley has the Federal 215M match magnum primer at a lower premium than the CCI, so I would go there for that particular kind of item.

Note that changing primers can change your pressure, equivalent to up to about 4% powder charge. If I switch primers (from any kind to any other kind, regardless of whether it's standard to magnum or vice versa; sometimes these little guys fool you) I drop my charge weight 5% and use my chronograph to work back up to the same muzzle velocity I got from the other primer. I save a few of the old primers so I can fire the old load on the same day and under the same light conditions for the comparison. Achieving that match makes the pressure and barrel times pretty close to the same, and that usually puts you back on a sweet spot or very close to it.

(Note that the above assumes you haven't changed powders or even powder lot numbers. With a different powder or lot number, peak pressure may be rather different even when velocity matches.)

You can often achieve the above in just one step. Take the velocity from the original charge, divide by the velocity from the 5% reduced charge with the new primer, then multiply the 5% reduced charge by the result. It usually comes quite close in a rifle. If the load is compressed, though, I would go back up in steps not exceeding 2% of the old charge, just to be sure a spiky behavior doesn't show up in the process.

old roper
August 11, 2011, 07:24 PM
jepp2, I was at the Sportmans Warehouse here in Colorado Springs and I saw the prices of the CCI BR4 primers.

If you look at the results from the BR matches 6ppc you see most use Fed 205M. Myself I use Rem 7 1/2 or Fed 205/205M primers.

Slamfire
August 12, 2011, 10:24 AM
I know a number of competition shooters who use CCI Benchrest primers. My bolt gun gunsmith is a Long Range Champ, these are his staple. They are excellent primers. So to are Federal match, though I do not recommend Federal primers in Garands/M1a's. Federal primers are too sensitive and are the most slamfiring primer around. A bud of mine who is a F Class National Champ, he used CCI Benchrest, Federal match, all depends on what primer he developed the load.

Today's primers are very good and very consistent, even the standard grade primers.

The only way to know if they will make a difference is on paper. Primer effects are small compared to bullets, barrels, bedding, and powders.

Though a Wimbleton champ told me groups with small rifle primers in medium cases were 25% smaller. The unfortunate thing was misfires in cool weather.

Jimro
August 12, 2011, 11:56 AM
I've not used CCI BR4's but have literally ran though thousands of BR2s for my 308.

In a word? Try it in YOUR rifle with YOUR load work up and see if there is a difference. Generally my 308 handloads will hold 3/4 MOA from any rifle they are ran through. I'm not chasing "one ragged hole" so anything sub MOA is good for me.

Jimro

amamnn
August 12, 2011, 04:11 PM
When looking what we think might be the the most favored primer among BR shooters, there are some other factors to be considered.

What is ballyhooed online--even at benchrest.com and 6mmbr.com is not necessarily what people are using to win matches--or even what most people who shoot BR are using. If you try to use those sources as guidelines to help your accuracy, even in a REAL BR rifle, you are quite likely to be mislead.

If you want to find out what people who are successful at that game are using you need to read the equipment lists in the NBRSA newsletter or in Precision Shooting, the semi-official newsletter of the IBS. You will find that primer choice is mostly as Nick says among the short range BR shooters, but it is no means unanimous. The Federal 205M is far and away the primer of choice among those folks who load a 60ish gr. bullet in a 6PPC cartridge using N-133 powder. There are other choices that crop up from time to time. The nice thing about reading these match results is that they show not just what Jackie Schmidt or Tony Boyer or Lester Bruno or Jack Neary used at the Cactus or the super shoot, but what the regular guys in the trenches are using too, and what finished well in local matches.

The long range guys are not shooting the same cartridges as the shorties. A more energetic primer appears to be favored at least in the last few years of 600 or 1000 yard results I've seen. CCI and Remington primers are more often seen here.

Each chamber and barrel is a law unto itself. While a lot of us find that a milder primer in a short range cartridge gives better results since it does not start as harsh a vibration g harmonic in the barrel, it is by no means a guarantee of improved accuracy. I have a shot few thousand Rem 7-1/2 that I bought when the Federal 205Ms were impossible to get. I thought that I would use them in fire forming and the first stage of load proving and save my precious 205s. They were cheap and available. To my surprise a couple of the cartridges I shoot do better with certain powders and bullets when using the harsher Remington than they do when using the milder Federal primer. These are short range BR loads in 22BR and 30BR.

Go figure.

Unclenick
August 12, 2011, 04:23 PM
You do hear of that. Charles Petty get that result from his Cooper Phoenix in .223 in a series of Handloader articles in 2006. The hotter Remington primer grouped best at 100 but had the worst MV SD, so, at long range it presumably would cause too much vertical stringing. What I also noticed was his bullet (55 grain V-max, IIRC) got about 150 fps more out of the same 24 grain charge of Reloader 10X than he did with a 205M, which had the lowest MV SD's (also, IIRC). So, I was left to wonder if he had brought the charge up about half a grain with the 205M (QuickLOAD's predicted compensation), if it would not have given him similar accuracy without the MV ES? He didn't do it, so I don't know.

I've also acquired some 215M's to play with in the .30-06 where my loads don't always fill the case well, but have wondered about the Tula/Wolf KVB primers for 7.62 and 5.56. Presumably these would be their version of military hard and magnum strength for cold weather ignition.

So many things to try, and such limited time.

crowbeaner
August 12, 2011, 07:50 PM
I've used them both; the RP is what my best load uses. I use the BR4$ with another load. Price is not a consideration, results are.

old roper
August 12, 2011, 08:52 PM
amamnn, I don't disagree with you but some put to much into the primers just to prove their an expert.

Here is an article on Jackie Schmidt testing IMR 8208.

Jackie mention type primer and at the end of article mention condition of the primers. There is no mention of primers as a factor during the test.

http://www.gunslot.com/pictures/jackie-schmidt-tests-new-imr-8208-xbr-powder-%E2%80%94-results-are-very-impressive