Seating depth

[Mikemontminy]

The conditions haven’t been stable enough for testing. Always windy. While doing a bullet seating depth test with Berger 105 vld’s in a Dasher at 300 yds should I be looking for the least amount of vertical or smallest group overall.

 

[BradY]

If your at the point where your testing seating depth you should have a window of seating depth where it’s all consistent. Might be as small as 3-5 thou, might be as large as 10-20. Only testing will confirm. If your powder charge is in a node then seating depth should bring it in tight. If not tight and consistent then maybe switch bullets. No point forcing a barrel to shoot something it won’t like.

 

[KenOath]

View attachment 1046684 The conditions haven’t been stable enough for testing. Always windy. While doing a bullet seating depth test with Berger 105 vld’s in a Dasher at 300 yds should I be looking for the least amount of vertical or smallest group overall.

In general I will do a powder charge test first to find a charge window which gives the least amount of vertical then try those charge weights with a number of different seating depths which should tighten groups horizontally..

 

[dmoran]

@Mikemontminy
Vertical dispersion is key for LR, in my experience (also for Mid range).

 

[Dusty Stevens]

Looks like you need windflags and learn how to read them. Those groups are what we call a “weather report”

 

[Mikemontminy]

Everything was shot with wind flags. The wind has been terrible all month for testing. 15 to 20 mph switching back and forth. Just trying to work up a load for a used Dasher I picked up that I would like to use for midrange F-class. So far It hasn’t matched the performance of my 6mm Br. I did a couple ladder tests at 500 yards using a camera system to record impacts. The load I picked from that was 31.6 gr of Reloader 15 at 3017 f.p.s. Let me know if you see something different. This was a narrowed down version of the first ladder .

 

[Stan Taylor]

I don't know a 100 percent but I have never seen a 6 dasher with that kind of velocities with that much powder in R15.

 

[dmoran]

@Mikemontminy -

I know there can be big differences in powder lots at times, but like @Stan Taylor noted above, I neither have seen RL15 produce that kind of velocity from those light of charges in a Dasher. It generally takes 32.5 to 33.0 for me to get into the 3000-fps levels. What chronograph are you using?

Myself like the 31.7 zone from your ladder.

 

[KenOath]

View attachment 1046971 Everything was shot with wind flags. The wind has been terrible all month for testing. 15 to 20 mph switching back and forth. Just trying to work up a load for a used Dasher I picked up that I would like to use for midrange F-class. So far It hasn’t matched the performance of my 6mm Br. I did a couple ladder tests at 500 yards using a camera system to record impacts. The load I picked from that was 31.6 gr of Reloader 15 at 3017 f.p.s. Let me know if you see something different. This was a narrowed down version of the first ladder .

Load testing in 15 to 20mph switching winds can and usually is a fruitless exercise in my experience.. we had some relentless winds here for over two months recently...you really had to be lucky to get a window to shoot in, usually at day break, some mornings I sat there for an hour or two for 10 shots or went home without firing a single shot. I’d rather wait than shoot in bad conditions where I struggle to make heads or tails of my results on paper. Load development can be VERY frustrating.

 

[Stan Taylor]

Load testing in 15 to 20mph switching winds can and usually is a fruitless exercise in my experience.. we had some relentless winds here for over two months recently...you really had to be lucky to get a window to shoot in, usually at day break, some mornings I sat there for an hour or two for 10 shots or went home without firing a single shot. I’d rather wait than shoot in bad conditions where I struggle to make heads or tails of my results on paper. Load development can be VERY frustrating.

Rusthythe wind is your friend.LOL

 

[Mikemontminy]

@Mikemontminy -

I know there can be big differences in powder lots at times, but like @Stan Taylor noted above, I neither have seen RL15 produce that kind of velocity from those light of charges in a Dasher. It generally takes 32.5 for me to get into the 3000-fps levels. What chronograph are you using?

Myself like the 31.7 zone from your ladder.

I’m using a Labradar which seems accurate checking Eley match in 22lr. I know it’s about a third of the Dasher velocity but pretty close to printed velocity on box. With a 100 yard zero I need exactly 8” of elevation at 500 yards.

 

[KenOath]

Rusthythe wind is your friend.LOL

Very true, I do find tougher wind conditions wipe out half the competition at our local club matches!!

 

[barefooter56]

View attachment 1046684 The conditions haven’t been stable enough for testing. Always windy. While doing a bullet seating depth test with Berger 105 vld’s in a Dasher at 300 yds should I be looking for the least amount of vertical or smallest group overall.

I suggest you look at the load that was shot on the target that is on the lower right side. Very nice water line! As was mentioned it is basically a "weather report" . Every shooter has their own way to do load development. I have always found the bullet seating depth accuracy node first. Then the velocity accuracy node. If the SD (standard deviation) number needed tweaked after that I move the bullet seating depth up and down about .002 from what the CBTO was to see which way I needed to go to fine tune a little further if necessary. If you have any more questions please feel free to contact us! Thanks for using our bullets !

 

[Mikemontminy]

I suggest you look at the load that was shot on the target that is on the lower right side. Very nice water line! As was mentioned it is basically a "weather report" . Every shooter has their own way to do load development. I have always found the bullet seating depth accuracy node first. Then the velocity accuracy node. If the SD (standard deviation) number needed tweaked after that I move the bullet seating depth up and down about .002 from what the CBTO was to see which way I needed to go to fine tune a little further if necessary. If you have any more questions please feel free to contact us! Thanks for using our bullets !

Had better conditions for testing this morning so headed to the range with some more berger vld’s loaded with different powder charges from 31.6 to 32.5 grains of Reloader 15. All seated with 20 this jump. Leaving in a hurry I forgot poles for my wind flags so had to shoot with no flags. Found a couple nodes at 31.8 (3016 f.p.s.) and 32.3 (3043 f.p.s.). The bolt lifted a little hard on the faster charge and the primer was a little flat so I may stick with 31.8. All shot at 300 yards with a lite breeze. The top target was 31.8 and 31.9 grains. The bottom was 32.3 grains.

 

[BT1]

Much improved. Good work. I have always started a new barrel at 300 also. Maybe go back and test the best of the lot with different seating depths. Vertical less that 1/4 is good, best loads should shoot closer to 1/8". Your 2 groups on the right look like they qualify. Many have seen good results with the VLDs even jammed up to 15. Then cherry pick the best vertical loads from them and move to the competition distance with 5 shot groups. If you are so inclined repeat with a primer test, although most times not significant, but worthy of a test. You sure are on the right track.

 

[KenOath]

Yep the right two targets have same POI on target, elevation is good..your getting close..

 

[barefooter56]

View attachment 1047522
Had better conditions for testing this morning so headed to the range with some more berger vld’s loaded with different powder charges from 31.6 to 32.5 grains of Reloader 15. All seated with 20 this jump. Leaving in a hurry I forgot poles for my wind flags so had to shoot with no flags. Found a couple nodes at 31.8 (3016 f.p.s.) and 32.3 (3043 f.p.s.). The bolt lifted a little hard on the faster charge and the primer was a little flat so I may stick with 31.8. All shot at 300 yards with a lite breeze. The top target was 31.8 and 31.9 grains. The bottom was 32.3 grains.

You could try to see if you can "tweak" the load by testing at 32.0 and 32.1 grains. Might be that the hard bolt lift goes away and you crawl back onto the velocity node with out the pressure.