nononsence, got some questions for you about primers.

bpost

I have been loading for the better part of 50 years and have never had primer issues with off the shelf primers.  MILSURP ammo, sure from the early 1950's Commie block stuff that had misfires and hang fires, folded necks, brittle cracks and the like.  15 years ago Tula primers in SRM were the most amazingly consistent I have ever seen across a chrono.

I can only think of a few rare instances where an off the shelf primer failed to fire or gave erratic ignition.  Maybe 4-5 total out of a 100,000 or so shot.

In your experience are primers that important in getting accuracy and consistent ignition assuming perfect powder charges and perfect bullets?

Thanks for your thoughts!

XXCross

In a word ..YES...as are things like the consistency of the depth of the primer pocket and depth to which the primer is seated.

BikerBob

Here is a link to an interest article about the effects of different primer manufacturers on shotgun shells.

I would expect given the size of the barrel and the shot patterns that this would drive a larger observed variance in rifle consistency due the the measurements of the single projectile vs. a pattern of many projectiles.

http://www.armbrust.acf2.org/primersubs.htm

nononsense

Sorry about the delay but I got called away to work on a couple of horses.

As much as I would like to emphasize one component over all the others, cartridges are still a system. Each one has to be selected for the accuracy level you’re looking for. It is the interior ballistics which are effected by the powder/primer combination and the exterior ballistics reaction (bullet) to the interior effects. Without all 3 working in concert together, your concept of accuracy will suffer. Put a low quality bullet on top of a great powder/primer combination and you get mediocre performance. The converse is true with a great bullet over a lesser powder/primer combination.

It is a truth though that primer selection can have a significant effect on accuracy at the target. A nominal hunting load performing at a 1” group can sometimes be improved by selecting a different primer. This though is still dependent on the ability of the rifle system and the barrel. If you’re working with a tested benchrest rifle and you’re seeing 1/2” groups, a primer change is mandatory. So it sort of depends on the type of firearm, it’s use and the necessity for significant testing. Narrowing down the use and the standardized accuracy of a particular firearm will help you gage how much potential there is for change. 

Factory rifles have seen significant improvements on=ver the last 20 years but do not expect benchrest groups simply by switching primers.

Best.

toad67

I was recently trying to figure out what my vanguard in 240 Wby liked. I could consistently get 1" groups with the 85 gr Barnes TSX bullets with Federal and CCI primers. Just for giggles, I tried some Winchester primers, consistently shrank the group size by 50%. Winchester primers aren't generally the most accurate primers, but in this case, the combination was great.

nononsense

It never ceases to amaze me about which primers provide the best groups. That’s why we say it’s a test to switch primers when testing powders and bullets.

Best.