Home Forums Reloading Big Game Rifles Match grade primers?

Have I seen them or am I thinking of brass?

In working up a load I have been going hog wild with measurements.
Started with average weight of primers weigh the group I am using for the present bracket loads divide by x.

Went to individual primer weighing when my pre /post charge weights were not quite jiveing. That helped. Was seeing .01-.03 variation in unused primers.

Last set weighed the spent primers (post ultrasonic cleaning of brass) and I it seems like the spent weights don't quite line up for consistent burned mass.
I had actually gone the extra step of trying to select a set of primers with more consistent unused weights.

Have I seen match grade primers that are a touch more consistent?
Is the difference in mass consumed enough to move the landing points around a bit?

Thanks

In what situation do you believe you'll net any measurable benefit from this activity?

OP must be extremely bored.

Well Mathman.
It started as a means to QC the finished round.
Brass weighs x
Primer weighs y
Projectile weighs z.
Difference between x+y+z and mass of finished round should be the weight of the charge.

Then in course of my tabulating I recalled a high school chemistry lab involving the mass consumed by combustion.. .and the associated energy released...

So I figured that I would consult the Oracle...
And see what the tribal knowledge of the situation was...

I could, of course have a more solid shooting position...
And..
Since the mass of the primer is at one end of the beam (off it actually on the <10gn barrel) and the mass of a completed cartridge almost to the other end, the error of the instrument may play a factor...

But on the lower side of my last bracket I had a perfect diagonal string result, so either I found an anti-node, or there is another cause.

How that for a roundabout answer?

Seems like another variation of pissin' into the wind.

I remember buying some CCI Match Grade primers back in the early 1980's, haven't seen any for years. Don't see that weighing primers is an activity that would yield enough improvement in accuracy if any to be a worthwhile activity.

I used to use the CCI BR2 instead of the 200 all the time. In those days they were only a couple of bucks more per brick. A while back the BR2 shot up in price and that ended that. My local store has them for seventy something a brick.

Thanks GW.
I thought I saw some somewhere but could not clearly recall.

I figured that if a dent in the case could change pressure and therefore velocity, then a bit more umph out of a primer might as well.
Otherwise why have Magnum primers vs. Plain vanilla?

Just looking for sources of variation as I did not expect the stringing where I found it.

Though I guess one leg of the bipod could have sank a bit with each shot....

You will gain a lot more by ditching the bipod for a more solid rest.

Focus on the fundamentals first.

Match grade primers have a more consistent amount of priming mixture in them, that's the only difference from regular primers; cups and anvils are the same.

Priming compound starts out as a wet slurry, kind of like thick jam or peanut butter. The way it's put into the cups is to spread it over a perforated plate with the cups under each perforation, exactly like spreading peanut butter on a sandwich. It's as much art as science and some employees are much better at it than others.

The employees who show a knack for very consistent and even spreading are assigned to making the match primers.

I don't know if that actually helps groups since I've never used them but suspect you'd probably need a very accurate rifle to begin with to notice any difference. I just posted this since you presented an opportunity to interject some arcane gun knowledge I picked up over the years...

I agree with antelope sniper. Just my $0.02....you mentioned the bipod leg might be sinking with each shot causing stringing. Does this mean you're not shooting from a bench? I'm not the best benchrest shot, but I can sure do better, with regard to group size, from a solid bench than from any other shooting platform. That said, I seldom use a bipod from the banch. You can watch a rifle bounce off the bipod, it's just too hard of a rest, though steady, strange things happen at the shot if the rifle has any recoil at all...and they all do. POI will often change from a bipod to good sandbags. Be careful your sandbags aren't too firm. I learned from Mule Deer to try a soft towel tween the bag and the rifle, especially with light rifles, and it helps..

I do use a bipod for prairie dog hunting, but check zero from a bipod on the ground as compared to my bench zero. Minor adjustments are sometimes, but not always, necessary. And my groups are not as tight from the bipod as from the bench.

Unfortunately not going to happen in my present location.
Stuck with field conditions. The absolute linearity of the group was theo oddity.
Thanks though.

Thanks Jim. That is a good little tidbit. I figure that there might be something there.

I am going to try switching one piece of brass from the two sides of my bracket.
They have been in two groups for several steps.
This will give me one group with mass aligned to within .05 gr8 and two other measurements at .002"

The second group will have more brass weight variation, but the other two measurements will within .002" and it will get primers that are identical to the ability of my balance. The first group gets primers with a .02gn range (+/- 0.01)

I still have two variables but maybe things will be better.
Oh and I annaled too. The last step was the second since annealing.

Just another thought, you say you are stuck with field conditions. I understand not everyone has a good range to shoot from. On the farm, I use a portable bench (mine is by Knothole Designs out of Wyoming, think he has a webpage), and bags. It's close to as steady as the concrete bench at the local range. I use it for prairie dog hunting too, if I don't have to walk far from the pickup. Beats shooting froma tailgate or a bipod by quite a bit, and you can set up anywhere you can put up a target.

Maybe not. It can be a symptom of varying the cant of the rifle.

Perhaps you could get yourself a couple pieces of railroad tie. Get them nice and level, and put a real rest on top of that solid foundation?

With strawberry jam!

Thanks .300S it's a hike in kind of spot.

There is another slightly higher tier with a nice backwards j-shaped tree I might use. Comes out of the hill about horizontal about two-feet in diameter then goes vertical with a radius of about three quarters of an arms length...
Not sure I have a good line from there and my decline will bump up a bit from 5.7-ish

Thanks again A.S.

I'll say this: There are many ducks you need to get into a very tidy row before worrying about differences between individual primers, if ever.

"cups and anvils are the same." Not exactly. In all the "match-grade primers" I'm acquainted with, by actually visiting the factory and interviewing the manufacturers,the cups and anvils are formed from the same batch of brass, with the same machinery before it wears too much for acceptable results.

On the other hand, that will make exactly zero difference in OldManoftheSea's handloads--which is exactly as much difference as it will make in most handloads.

As I said it occurred to me based on variations between pre and post use weights.

John,
Thanks for chiming in. I have not heard much from you lately, but maybe we have been traveling different sections....
Thanks for locking in on the original question: do they exist? And how much effect might the variation in compound weight make?.

So they are the nth degree for heavy rifles, solid benches and indexing cartridge cases so they sit in the rifle the same way every time.....
Best-