Worked through 2 nodes and need some opinions.

[Buxndiverdux]

I've worked through two nodes and found 1/2 to 1/4 minute results in both nodes. Both of the most accurate groups were in the middle of the firing order.

I've been struggling to confirm these results, but have noticed something that might be a possible answer.

When I got back to confirm my groups, I've been firing a couple foulers on a clean bore, or a single fouler just to get some heat in the barrel on a dirty bore. These foulers have been some 168gr Nosler Ballistic tips I've had forever and just figured why waste 215 Bergers.

So my question is when I went to confirm my first node, I shot 2 168BT first since it was a clean bore. Then shot a 3 shot group, which was about 3.5". The next 3 shot group after about 5 minutes was 2 1/2". Another 5 minute wait produced a 1" group. All testing at 400 yards. All the same load.

The second node confirmation testing went almost the exact same way except I only shot 1 fouler and one group.

The first shot after the fouler was not where it should've been on paper. Bullet just hit at an odd spot off the normal area this powder and bullet combination have been printing.
The next 2 bullets shot in correct area 1" apart.

Could those 168gr BT's be laying some copper that the 215 Bergers don't like? Maybe takes a few shots to get happy?

I'm just about ready to try another powder since I can't seem to get any consistency.

What does the brain trust here think?

 

[Buxndiverdux]

118 shots down the barrel and all brass shot at least 3 times.

 

[wildcat455]

I had similar problems a long time ago, I don't even remember what manufacturer I was mixing. I vaguely remember some velocity and pressure issues.
Although I do not have the answer for you I can tell you what my solution was.
I stopped shooting mixed bullets/powders during load development, and shooting sessions. When I switch powders or bullets, I clean the gun down to bare metal for a bullet switch, and powder residue for powder switch. (as long as the same bullet is used.) The only exception to this for me is bullets of the same type from the same manufacturer. I.E. Hornady ELDX and ELDM. I'll also shoot bullets with the same manufacturers designation, but different weights, I.E. Berger Hybrid Target 200, 215, 230 or in the Elite Hunter series 250, 300. I won't mix say, Berger Hunting with Berger Hybrid Target, or Sierra Game Kings with Sierra Match Kings, just because I don't know if jacket material is the same.

I have no empirical data to support what I do, but I did quit having those problems. So I stuck with it. Quite likely I'm doing more work than is necessary, but I've been doing it this way for so long I don't really even notice truthfully.

Good luck and let us know how you make out!

 

[Canhunter35]

I've had trouble with changing bullets also. Stick with the 215s and see how they do cold bore

 

[19 Badger]

I always clean the barrel out when switching brands of bullets.

 

[FURMAN]

Hard to tell exactly what you are saying but I will say a couple of things. It typically takes 6-12 rounds after cleaning to get the full accuracy the rifle is capable of. I have seen some very strange things shooting different bullet and/or powders. I stick with one combo until it will not work.

 

[Lonewolf74]

As others have stated I would stop mixing bullets during any load development and in fact once break in is done and I've found a bullet I know the rifle likes I tend to only let that bullet down the tube.

Next I would stop cleaning the barrel during load development. Again once past break in you should not have to clean more then once every 150 rounds unless you have tested and confirmed that accuracy drops off after XX number of shots. As others have stated it seems to take most rifles 5-10 shots to "settle" after cleaning and from what I've seen even a few more shots if running coated bullets.

 

[Buxndiverdux]

Ok. Thanks for the info.