want to see a rifle go "out of tune"

[bill123]

so the rifle is a 6mm dasher used in 600/1000 yd br
rl 15 cci 450 lapua cases barts 105
the group on the left is my current competition load
0.167 with less than 20 thou vertical
the next three "groups" are each 0.1 gr up in powder(+.1.+.2,+.3)
there was a slight right to left breeze.
notice how they grow in VERTICAL...THE HARMONICS/the tune going away.
that is tune going away. i could keep adding powder till it comes back..if it does before i max out.
i actually like the node i am at, there is one lower.View attachment 133529

Great example Thanks. So how do you keep the load in tune as the barrel wears? Are following a MV, chasing lands??

 

[ar10ar15man]

no it does not.
0.1 plus or minus .1 for an rcbs 10/10

My rcbs 10/10 scale does measure .01 increments....a

 

[ar10ar15man]

both , but only time will tell. still good at this point. about 500 total , but this bullet i just started with.

Great example Thanks. So how do you keep the load in tune as the barrel wears? Are following a MV, chasing lands??

 

[therifleman556]

Where do you begin? Charge weight or seating depth?

 

[Don A Parsons]

I call it chasing the lands,,, we do this on the big bore units.

Roughly 200 shots, check cone where the lands start,,, if burn is happening,,, we reset the jump,,, if not,,, we run another 200 ish and check again...

We like to do this at the end of the weekend so we can reload for the following match,,, 5 to 7 thou won't make alot of difference until we shoot another ladder and box test part way through the month...

Its not uncommon that we luanch 7 to 800 rounds per month as the season ramps up... Then 200 rounds for hunting season as we test fire the irons through the harvest adventures. Ha...

Hunting is no fun unless we shoot frozen rocks and trees. LOL...

Each shooter finds their method to the mad-ness,,, we enjoy the extra tinkering since it gives us something to do,,, it let's us know if the boolitz will land on target with 12.43 MOA @ the 600 mark.

 

[Capt RB]

The tight windows shown for AR10AR15man's dasher show how a small case can be very tough to stay in tune on comp day. The .1 in a dasher is far more change percentage wise than that same .1 in a 308 based case or magnum sized case.
It also shows how important it is to know how tight that window may be. SHow up and the temps drop 20 degrees and you lose that tune without an adjustment with say RL15 for example
Thanks for sharing AR10AR15man!!

 

[ar10ar15man]

it depends on how you got to the final match load.
in my case i use charge from on the lands and then adjust length.
with this bullet, 12 thou off was a sweet spot, so i will start with it at 12 off and adjust powder.

Where do you begin? Charge weight or seating depth?

 

[John Klingenberg]

I built my 6 br two summers ago and found an awesome load for RL15. shot nice little groups. Later that year we had a break in weather late November. I took her out to do some group therapy. The same rifle and ammo I had loaded in summer opened up to about 3/4 inch. The temperature change was around 50 degrees. I checked and rechecked everything. Tried a more stable powder and haven't loaded with RL15 since. Varget is my new go to for several cartridges.

 

[ar10ar15man]

so i have heard.
i am the one guy in the world that never got varget to shoot. traded it all for 15 and am happy. i do check the weather before i go to a match. i have a 30br that would not shoot LT30 when i was in colorado. went back to 4198. retired to az. on a whim loaded up a bunch of rounds to retry lt30 .....OMG no schit.... i shot 6 zeros as in 0.0x, i had nine groups with an average of 0.09x . guess what i shoot now..
yep everything counts

I built my 6 br two summers ago and found an awesome load for RL15. shot nice little groups. Later that year we had a break in weather late November. I took her out to do some group therapy. The same rifle and ammo I had loaded in summer opened up to about 3/4 inch. The temperature change was around 50 degrees. I checked and rechecked everything. Tried a more stable powder and haven't loaded with RL15 since. Varget is my new go to for several cartridges.

 

[therifleman556]

So do you have different loads ready to go based on conditions?

 

[ar10ar15man]

not me. i know others that take prepped brass and vials with powder.
i know some that tune the day before, load that night.
this is close to what is done in short range br where loads are changed thru out the day.
the level of competition at 1000 is way beyond what was done just 5 years ago.
i do have a van i will be able to load in on site, just not yet
i take a load that looks good for the predicted conditions.

So do you have different loads ready to go based on conditions?

 

[John Klingenberg]

So do you have different loads ready to go based on conditions?

No I just load the one load and use it year round. If I was a competitor I probably would but I just like to sit and bang out little holes in paper or shoot tiny targets like rocks and such on my berm.

 

[26Reload]

no it does not.
0.1 plus or minus .1 for an rcbs 10/10

I stand semi corrected....
But still the 10/10 scale can be dialed to a more precise load than a lot of scales...if you electronics match up well(whose to say how close they actually are weighing) then the 10 cylinder dial can be adjusted to allow in between measurements rather than just the .1....as I used it that way myself... incrementally....guesstimated.....but more accurate.....
I trusted my increments much more than the electronics that didn't weigh even close to my adjusted 10/10......

 

[ar10ar15man]

yes you can do that,
but you do not KNOW what that weight is.
the scale is only "certified" for plus or minus 0.1
i agree cheap electronics are worse than most beam scales.

I stand semi corrected....
But still the 10/10 scale can be dialed to a more precise load than a lot of scales...if you electronics match up well(whose to say how close they actually are weighing) then the 10 cylinder dial can be adjusted to allow in between measurements rather than just the .1....as I used it that way myself... incrementally....guesstimated.....but more accurate.....
I trusted my increments much more than the electronics that didn't weigh even close to my adjusted 10/10......View attachment 133680