Ruger Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
964 Posts
Discussion Starter · #1 ·
I bought some Vhitavuori powder to use with some heavy .223 bullets. I decided to use the Vhitavuori online loading data from their website. It had my exact bullet and I settled on slightly above the middle weight and made 30 rounds, I could have gone one grain more per the data but I wanted to be conservative. Since I used Hornady bullets I later looked in my Hornady manual and their max load is .6 grains less than what I used. I called my buddy with Quickload and he told me that it showed I was a little over NATO 5.56 load pressure.

How can different reloading data sources be so different?

I'll likely pull the bullets and reduce the charge per the Hornady book and chrono them when I get the chance. Of course if I was shooting them in a Ruger I'd probably just leave them as is and not worry about it.
 

·
Registered
Joined
·
449 Posts
What guns were the various loads tested in? What's safe in one might be unsafe in another. Components and other differences, like seating depth, can make a big difference in loads. Start low and work up loads until you get signs of excess pressure in your firearm, then back off until you get the best accuracy. Be consistant.

That's the way I do it and, I believe, the most recommended method.
 

·
Retired Moderator & Gunsmith
Joined
·
18,526 Posts
scooter.maclusky, This is a very common event. VVH uses the European CIP pressure standards which are notably higher than US SAAMI pressure standards for a 223 Rem. CIP measurements are taken at the case mouth versus the case body for SAAMI. Have your buddy look at QuckLOAD again .... CIP max pressure is 62,355 psi versus 55,000 psi for SAAMI. Although these two loads may use the same bullet, are they both seated to the same depth (COL)? If not, that would account for a significant difference too.

All loads listed in Speer, Hornady, and Sierra reloading manuals are tested and comply with SAAMI max pressure ratings .... meaning they never list a charge that will produce pressures in excess of SAAMI standards. Nothing says the manuals have to go clear to the max powder charge, in fact I've found Hornady tends to be a bit conservative whereas VVH tends to go right to the edge.
 

·
Registered
Joined
·
126 Posts
Yeah, what he said :)
I never understood why some of the manuals were off. That sure makes sense. I use the Lee Reloading Manual. Hardcover book with lots of great information.

scooter.maclusky, This is a very common event. VVH uses the European CIP pressure standards which are notably higher than US SAAMI pressure standards for a 223 Rem. CIP measurements are taken at the case mouth versus the case body for SAAMI. Have your buddy look at QuckLOAD again .... CIP max pressure is 62,355 psi versus 55,000 psi for SAAMI. Although these two loads may use the same bullet, are they both seated to the same depth (COL)? If not, that would account for a significant difference too.

All loads listed in Speer, Hornady, and Sierra reloading manuals are tested and comply with SAAMI max pressure ratings .... meaning they never list a charge that will produce pressures in excess of SAAMI standards. Nothing says the manuals have to go clear to the max powder charge, in fact I've found Hornady tends to be a bit conservative whereas VVH tends to go right to the edge.
 

·
Registered
Joined
·
964 Posts
Discussion Starter · #5 ·
Iowegan, thanks for the reply. Both reloading sources used the same COL of 2.260 for the same Hornady 75 gr bullet. The only difference is the case. VVH using a Lapua case trimmed to 1.752 and Hornady using a Winchester case trimmed to 1.75.
My PMC cases were trimmed to 1.751. I think I'll shoot one and look for any signs of pressure before I pull all 30 since I'm one grain less than max published load and each charge was individually weighed before going in the case.
Now my Lee reloading manual indicates I can go .5 grain above the VVH max published load. Yikes!
 

·
Registered
Joined
·
964 Posts
Discussion Starter · #6 ·
update

Shot them yesterday, very accurate and no over pressure signs. Glad I did not pull them, thanks again Iowegan! Out of respect for this hobby I scared myself.
BTW, Vhitavuori powder is the cleanest burning I have ever seen.
Vhitavuori published load of 24 gr N140, 75 gr Hornady BTHP, COL 2.260.
 
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top