does anyone know how (if) a regular cci primer will change a load that uses a rem 9.5 primer?

It depends but rule of thumb is back off and work up to max again.
I'd come back 10% then see what happens

Changing the primer may have some change in the poi, but the only way to know for sure is to try it.

The 9.5 is a hotter primer and changing will affect the load. Whether or not it changes your load noticably is something only you can tell.

It varies w/ th epowder & the cartridge. In my 260ai, there is almost zero pressure diff. showing up as vel. on my chronograph. Accuracy does vary sometimes when using mag primers w/ powder charges that don't need them. I would back off 1gr & work the load back up 10% is pretty conservative.

9.5 is a standard primer. There may be a slight difference in some calibers. You can load -.5 gr, same load, and +.5 gr. to see for yourself.

In one of my loads (a 257 Weatherby if I remember correctly) Remington primers needed 1 to 1.5 grains more powder (I don't remember which powder) to give equivalent pressure signs compared to the CCI primers.

You are unlikely to notice any discernable difference. Rarely, a primer change will appear to make a difference in grouping, but most people never shoot enough groups with the two different primers to effectively rule out chance.

I'm glad someone brought this up.

ALL of my load development has been done with WLR primers, and that is what I've always used. (I don't know what primers were used when developing my 35 Whelen loads).

it is almost impossible to find WLR anymore... I can get CCI Large, CCI large mag, and sometimes Rem or federal, but I don't know how they compare to the winchester pieces.

anyone?

In working up loads I frequently try different primers. In medium to large rifle loads, I've found no need to make load adjustments when switching between CCI 200, CCI 250, CCI BR2, Federal 210M, Federal 215M, WLR and WLRM primers. The only significant difference I've found is that Remington primers seemed to need a little more powder to get loads equivalent to the others.

There is very little explosive in a primer so it contributes to the overall pressure developed by a cartridge. For cartridges the size of 308 Winchester and larger, I've found I can interchange primers with impunity unless the load was originally worked up with Remington primers.

Smaller cartridges such as handgun cartridges are a different story. In working up 44 Mag. loads, I tried CCI 250 (large rifle magnum primers) and had to decrease my load of H110 by about 1.5 grains compared to loads with CCI 350 (large pistol magnum primers).

Also, primers usually don't seem to make a whole lot of difference in how accurate a load is but I've found some notable exceptions so it's worth trying different primers if a load isn't doing just as you would like it to.

quote:

Originally posted by Dark Helmet:
I'm glad someone brought this up.

ALL of my load development has been done with WLR primers, and that is what I've always used. (I don't know what primers were used when developing my 35 Whelen loads).

it is almost impossible to find WLR anymore... I can get CCI Large, CCI large mag, and sometimes Rem or federal, but I don't know how they compare to the winchester pieces.

anyone?

The standard WLR is slightly stronger than most "standard" LR primers. It is probably pretty close to the CCI 250. That said, probably any "standard" primer will provide you with similar performance. The biggest difference you will find is the seating pressure needed with other primers compared to the unplated WLR. The WLR seats very easily (in fact, it seems somewhat loose). Most other primers will require a firmer push to get them fully seated. This, of course, has nothing to do with load performance, but I thought it merited mention.

Remington primers fail to fire 10x more than any other primer I've ever tried. I had almost 50% failure in my 45-70 and 45-120 with Remington primers, and the one I tried in my 6mm Ackley failed. In all other guns combined I've had one FTF with CCI's, and a couple with Winchester.

I don`t know how true this ranking is but it is very similar to one I saw a while back in Handloadser magazine. It shows the brisance of the various primers that are popular today.

http://www.castingstuff.com/pr...esting_reference.htm

quote:

Originally posted by Tyler Kemp:
Remington primers fail to fire 10x more than any other primer I've ever tried. I had almost 50% failure in my 45-70 and 45-120 with Remington primers, and the one I tried in my 6mm Ackley failed. In all other guns combined I've had one FTF with CCI's, and a couple with Winchester.

Interesting, the only rifle I use Remington primers in is my 375 H&H. I'm just about finished with my second brick and I've never had a single misfire.

My experience has shown the CCI to be the most inconsistant quality control wise. I have yet to have a WSR, WLR, WLRM, FED 210, 215, 215M, 205 and Rem 9 1/2 ignite. That being said I have had the worst luck with remington primers working up loads that produce good groups.

quote:

That being said I have had the worst luck with remington primers working up loads that produce good groups.

Just goes to show how these things go in cycles. Thirty-five years ago or so, no one, and I mean no one, would shoot anything on the benchrest circuit other than Remington 91/2 primers.

As far as reliability, I've never come across an unrelialbe primer. If the gun doesn't go "bang" when the trigger is pulled it is almost always some problem other than the primer. The exception might be "military grade" primers which have a very tough cup to resist slam fires in certain autoloaders. Some "civilian" rifles don't have enough punch to set them off reliably.

Rems are 10x worse. Interesting. I think I'd look to my guns mechanically. I've used CCI for more years than I'd like to remember but about 5 years ago I switched to Rems with my small rifle shooting. Lotsa matches and Pdog shooting. No ftfs to date.

I hope this is of use. I worked up loads for my 270 Winchester using Remington and CCI standard primers. Using 55.0 grains of H4831 with a Hornady 150 grain bullet.

With CCI the average velocity was 2809 fps and with Remington the average velocity was 2803 fps. So not much there...except...extreme spread over five rounds with CCI was 30 (THIRTY) fps. With Remington it was 116 fps!

So as THNDRCHIKEN noted:

quote:

That being said I have had the worst luck with Remington primers working up loads that produce good groups.

That may be the reason and I agree with his findings. Mine are the same.

This from a 23.50" barrel BRNO ZKK 600. So for consistency I favour the CCI product.