Load workup & primer selection

[yellowfin]

Load development, I am learning, is very time consuming, so I'm wondering about something in regards to the variable of primers. In your experience, do you do your ladder loads all with one primer first and try the best powder and weight later with different primers? Or do you do each increment with each primer choice, as any combination might work at any time without regard to how it does with others? I've got 3 different bullets, 3 different powders (to start, yes, I know I'll do more later) and 3 different brands of primers with 5.56 so wondering if I can take a shortcut somewhere.

 

[mojavejim]

I'll play with primers after I find a load & test with the same.

 

[Sendit6.5]

I'll play with primers after I find a load & test with the same.

I pretty much do this. It's the last variable I'm likely to mess with.

However, I HAVE had a couple situations where I had strange results early on in development that led me to try a different primer. In those cases I was trying something like a magnum primer in a non magnum caliber and once I heard a rumor of a bad lot. So I tried swapping mid stream. Normally, though, I wouldn't mess with primers except to refine a load or to check the effect in case I was worried I might not be able to find more of a particular (i.e. Federal 210m) primer.

 

[GhengisAhn175]

You have to be doing primer tests when you're looking for the node window.

What's the point of doing a primer test AFTER you do a charge test with another component? That's the equivalent of doing a charge weight test with H4350 then switching to IMR 4451 or IMR 4350 expecting it could possibly be a better powder. Or bullet. Or case manufacture.

No one really devoted to this way of testing because it is consuming. Only a handful of benchrest guys I know still do it (because their discipline calls for it).

If youre trying to do primer tests and save the amount of loads you have to make, you can start with one powder and cover your normal wide range.
Then when you find your range, go +\- a full grain each way with the other powder. Should save you some.

A really good example of this is what Laurie holland did with his huge "primer test". Post test several things were pointed out, main one being that the test was skewed because he had a set load and only changed the primer.

Theres another test that was done regarding the use of various primers in different temps. While it was more geared towards magnum primers vs non, a similar secondary result was derived that changing primers may change your node windows.

long story short, if you change primers with a set load & it happens to perform better, you lucked out and it's a fluke.

If it it turns out 'worse' then fine tune the powder charge

 

[Citius7]

As a safety side note to what the fine folks above have said. Changing primers should be done with care. What does not show any signs of pressure could have significant pressure signs with another. One poster above said start a full grain low and work up. I'd take heed there. Remember it's still 50,000+ psi 3 inches from your face. What a few rounds for a new primer just to make sure.