Q. for Felix re primers

[Blackwater]

You've done a lot of investigation on primers, it seems. I also think I've read somwhere that you have a background in benchrest, which I assume is where you found out a lot about the finer points of shooting, and the technical matters related? In a recent post, you mentioned that Federal primers tend to have the hottest flame and lowest impetus imparted to the bullet. Can you rate Win, Rem, CCI and any others you've had experiments with, or seen techincal tests of please? Just curious. May come in handy when playing with a load to know what primers are hotter or more forceful and which are milder, etc.

[felix]

Good question, Blackwater, but no real answer. In the BR world, heat and force must be as constant as possible, and the selection results down to simply following the leader, ie, the BR record holder as of late because everyone shoots virtually the same load. In the cast world, we have unlimited number of issues such as boolit hardness and fit, and we all know that is seldom consistent from boolit lot to another. Besides that, we often want to shoot speeds which are not optimum for the case size. These factors make us chose different primers for different applications. But, I can tell you that the most forceful primer by far during the 1995 trials was the Winchester Large Rifle magnum. Save this primer for the longest of cases, i.e., the belted magnums. ... felix

[Blackwater]

Well, that's sort'a what I was afraid you'd say, generally, but thanks anyway. The more I learn about reloading and all the technical stuff, the more I realize it's always going to boil down to letting the target and general load behavior that's going to be the only final arbiter we're ever going to get.

One reason I asked is that a buddy was shooting 6.5 and 6.7 gr. Red Dot in his .45 LC Vaquero, and just by changing from WLP's to CCI std. LP's, he basically halved his groups. He shot quite a few 1" 25 yd. groups with that gun, but traded it off after a time for something he wanted more. Sometimes it's just amazing to find a small change like that make such a difference, and I guess that's a good reason NOT to shoot the same old proven loads all the time, except for really serious position shooting to keep your abilities up, but to keep trying new stuff just to see what happens. Sometimes the magic's there, sometimes you just learn what doesn't work as well.

Sure keeps it interesting, doesn't it?

[StarMetal]

Blackwater

Felix said something important here. He said as of 1995 the hotest primer was Win Large Rifle Mag. Don't for one second think that primer mixes don't change from year to year or lot to lot. You can't go by what Felix found in 1995. Heck powders are slightly different from just lot to lot, alone over a big year span. Bottom line is you have to find out currently for yourself and when you find what you want buy a large number in the same lot number.

Joe

[Blackwater]

Yes, you're right. What I was lookinig for in the original question was merely some glittering generalities that might serve as a guide for loading and checking out primers more "systematically," if you can call it that, or at least something to take an educated guess when I wanted to go in a particular direction. I know just enough about primers to know there's a lot I do NOT know. I haven't seen many instances where the primer made much difference, but there have been some. This is with hunting rifles, not the super accurate bench guns, so it's a lot harder to tell a real difference, and it has to be a significant one. Still, it does happen on occasion, and it looks to me like reduced loads for cast may (?) wind up being more responsive to a simple primer change.

I've shot mostly '06 sized cases through the years, and the WLR has become my go-to primer of preference. I've used every major brand and type of primer, all with good success. Only complaint I really have is that back when I used them at least, Rem rifle primers showed the most variation in trying to "read pressure signs," when I had more faith than I should have in such things. Some flattened out a lot, and some would be very rounded after firing. I didn't know if it was actual pressure differences or variations in the primer cup's metalurgy or heat treat (if it gets any?), or what. All I knew is the variation was something I didn't like, so I quit using them very much. I've never really been disappointed with WW, Fed or CCI's in any way, so have tended to stick with them. Others' experience will vary, of course.

Sure keeps things interesting, though.

[John Boy]

Couple of items related to the subject ...
(1) Testing of various primers, measuring force in a DMS ;-) manner!
http://www.castingstuff.com/primer_testing_reference.htm

(2) Single Shot Rifle Journal, May-June 2003: Table of Primers that measured 'Apparant Primer Energy, as a Function of Bullet Displacement' lists the Win-WLRM having the highest value (1.83") for Average Movement (inches). The lowest was: Fed-150 (0.932")

Regards
John