Pioneering...need help from a quickload owner please...

[Doublezranch]

Zayne and I are in the mists of using RL 33 with a 190 matrix in a 7 Rum. This is Zayne's rifle and he is doing all the shooting. We have done some testing already and are very miffed with the results. Wonderful accuracy but the charges are astronomical. No pressure yet and we are up to 102 grains. Cases still coming out dirty and small dimpling below the shoulder. I am wondering if the cases are too hard and need to be annealed. Also, Riley (barnesuser) thought dropping the charge and seating them into the lands .005 would help. I want to see if quick load can spit out a charge range and then compare it to the charge range we are at. If it's not too much trouble, I would like one for retumbo as well. COAL is 3.980. Thank you for considering this favor.

Jayson

 

[Deleted member 46119]

I get 3173fps @ 81k psi.

This may be a chambering where QL falls down. Too overbore? I got that with the Nosler designs and heavies.

What is your velocity, I may be able to make adjustments to the QL parameters.

 

[Doublezranch]

This is blistering for a 190...the average is a shade higher but this is first shot cold bore.

 

[Lefty7mmstw]

ZZ, I am not using any rl33 in my 7mm's... I've tried it in both the 7stw and 7rum and was less than enthused with the results. I've been on rl25 for the 7stw and either retumbo or rl50 for the 7rum. I'm not sure we can put enough load on the powder to get a decent burn in the 7mm's. The 300rum and a 225, now that IS another story...

I'm not quite sure why rl50 with 168 (vld match) berger's works, but I am at 95 grains rl50 and a 168 and the pressure is getting up to my max. already... 89 retumbo and the 180 sierra (or 175 hdy)seems to be the heavy bullet ticket for my rifle.
I am running a 3.770" oal on the 180's and a 3.810" oal on my 168's in my 7rum... The 175's are at mag length...

How many cycles are on your brass and how are the primer pockets holding up???

 

[Doublezranch]

I have less than 4 loads on the brass. Pockets are still very solid. If I can't get enough powder in there I'll be headed to Retumbo. However, I haven't had the best luck with retumbo but maybe this is the round it will work in.

 

[Lefty7mmstw]

ZZ, bring your rifle the next time you come through... If you try for a Saturday I can get out to a 200 yard range with you (only ten miles from my house); if you bring some stuff with we'll cook up some loads and work with them... We've got a couple of chronos here but if you want to bring yours by all means do...

As to the cycle count and pockets, you are running a long oal so you are going to get a bit more powder in at the same pressure; that's likely why you are not getting loose pockets at the charges you are running.
I worry that you may getting a funky pressure spike early in the burn as the bullet hits the rifling though. The 7rum has the freebore it has to lessen the pressure spike; I try to leave most of the freebore in play with my rifle.

 

[Doublezranch]

Alright... After many questions to many people all in which did a excellent job of helping me troubleshoot, my hunch was right. Riley and I spent the afternoon texting back and forth trying this, trying that. We both agreed that the neck tension was too little causing irradic pressure spikes. It was Riley's idea to seat deeper and to load 101-103 in half grain increments. Needless to say, problem solved. Pressure was nonexistent until 103. There was just a very faint ejector mark. Bolt was super easy to open on all loads. Now, to the numbers. I was using a Caldwell chrono which I know isn't a magnetospeed but It is what I have. Obviously the numbers are too erratic to take seriously however it does give me a good idea. Best group was less than .25 with 102.5 grains of 33. The numbers.....

 

[Doublezranch]

Here's a cool video of Zayne shooting. It's so cool watching that assassin muzzlebrake work....

https://m.youtube.com/watch?feature=youtu.be&v=pyZPNkFvv-Q