.260 Load development pt1

Reloading equipment, methods, load data, powder and projectile information.

.260 Load development pt1

Post by Elmer » 18 Sep 2017, 5:41 pm

Well, started load development for the .260 using Hornady 143gn eld-x bullets. Powder charges started from 40.5gn of AR2209 to 41.7gns , Lap brass, Fed match primers and all bullets seated 5 thou off lands.
Three shot groups at 100yds with the smallest group of .546" and the largest of .794....all charge weights were increased by .2gn increments.
The best groups started at .640" 40.5, .566" 40.7 and .546"at 40.9 , with group sizes starting to open up at 41.1 for .716"
The next batch of rounds will be 40.6gns, 40.8 and 41.0 ....then after that test I will be tinkering with seating depth to squeeze as much accuracy out of the Horandys.
Iam currently loading 5 thou off the lands, do have any suggestions for seating depth?, I have read anywhere from kissing the lands , right out to 25thou off.
cheers,
Sean
https://youtu.be/NtrBhEEe7ek
Elmer
Sergeant
Sergeant
 
Posts: 724
South Australia

Re: .260 Load development pt1

Post by Apollo » 18 Sep 2017, 7:14 pm

I and my old mate (Gunsmith) believe in a starting point of either jammed or at least touching the lands. Reason, simple. If you are going to adjust, you only have one option, not two, make them shorter.

I shoot 6.5x47 Lapua (3 Rifles) using 130gr bullets cause 140gr is too heavy in my view for that calibre. A 260 Rem then 140gr with it's extra power is probably ideal. I would do testing with bullets at least touching the lands, I would be loading 4 rounds per test in the same increments as you have done. Pick a perfect time and after a few fouling rounds shoot your tests allowing a bit of cooling time between, like a few minutes at least. Look at the best grouping of 3 shots out of the 4 fired then load more of those at that powder load but increase the seating depth.

Don't know if those Hornady Bullets are a Secant or Tangent Ogive. If Secant like a Berger VLD then they may even like being seated 0.120" off the lands. Only a test will tell.

I fine tune at 200 Metres and really do most testing at that distance, at 100m it's really a one hole group and tells me nothing. My interest is target shooting at 500 & 300 Metres. 300 Metres I expect 5 shot groups less than 1.0" but more like half that to be competitive. At 500 Metres my best is 5 shots in 1.120" but wish I could do that more often.

BTW.. My 300m comp has a factory rifle class and I did think at one time to try a .260Rem but I went with a .243Win which I won against a 260 that day. That was a Tikka T3 Varmint but the same barrel is now on a Sako 85 and for some reason is more accurate on a consistent basis, haven't used that in a comp yet but I'll see in a few weeks how it goes.

Best of luck with the 260. 6.5mm is a great, very accurate calibre.

BTW... Of your groups, I like the 41.3gr the best. It shows potential in elevation and windage being closest to a round group. Just needs to be tightened up into one hole.
Apollo
Warrant Officer C1
Warrant Officer C1
 
Posts: 1327
New South Wales

Re: .260 Load development pt1

Post by Elmer » 18 Sep 2017, 10:33 pm

Thanks for your reply Apollo, that sounds like a sensible idea starting with the bullet touching the lands, I reckon I will try that with the next batch and seat the bullet up to about 25thou in 5 thou increments. You sure have some accurate rifles there...looking at the 41.3gn group even though its slightly larger I see what you mean. That looks like a good load to do the seating test, thanks for your advice,
cheers,
Sean.
Elmer
Sergeant
Sergeant
 
Posts: 724
South Australia

Re: .260 Load development pt1

Post by Apollo » 19 Sep 2017, 12:15 am

Sean, in most calibres there are at least two accuracy nodes, some have three.

The Yanks, especially 1,000 yard shooters go for the top highest possible accuracy node. To the detriment it's very hard on cases pushing them to their limit but also that top velocity accurate load is not all that consistent from day to day yet alone all in one day.

My load and my mates is on the low side of loads, it stays consistent during a day from say 8.00am to 4.30pm and that's why it performs.

Now, if you are only into hunting then it's a slightly different story. You need a consistent cold shot accuracy but that too may be one from the lower node. We are only talking a hundred feet per second velocity difference perhaps, have not measured the high side as I always start low and pick my first best low velocity load. Wins for me in a lot of calibres even long distance varminting at home.

All the very best. One of these days I'll have to try a 260 Rem.
Apollo
Warrant Officer C1
Warrant Officer C1
 
Posts: 1327
New South Wales

Re: .260 Load development pt1

Post by Osty » 19 Sep 2017, 7:44 am

Nice video Elmer. You've probably mentioned this in another thread, but what powder measure/scale do you use? How confident are you in your 0.2gr increments?
Osty
Recruit
Recruit
 
Posts: 12
Tasmania

Re: .260 Load development pt1

Post by Elmer » 19 Sep 2017, 9:02 am

Thanks Osty, I use a digital RCBS POWDER MASTER? 750, I also work in Laboratories so I do a lot of weighing with scales that measure to 10,000th of a gram...yeah, you could say Im pretty confident with my weighing skills and the RCBS is a reliable little set of scales,
cheers.
Elmer
Sergeant
Sergeant
 
Posts: 724
South Australia

Re: .260 Load development pt1

Post by Osty » 19 Sep 2017, 11:23 am

Elmer wrote:Thanks Osty, I use a digital RCBS POWDER MASTER? 750, I also work in Laboratories so I do a lot of weighing with scales that measure to 10,000th of a gram...yeah, you could say Im pretty confident with my weighing skills and the RCBS is a reliable little set of scales,
cheers.


Thanks Elmer. Good to know you stand by the RCBS 750. Brought this up as I'm looking at getting a digital scale and wanted to know what you used.

Cheers,
Osty.
Osty
Recruit
Recruit
 
Posts: 12
Tasmania

Re: .260 Load development pt1

Post by Gamerancher » 19 Sep 2017, 11:29 am

Nice mirage in the video, we have a saying in BPCR silhouette, "never shoot in a boiling mirage". Just sayin'.
User avatar
Gamerancher
Sergeant Major
Sergeant Major
 
Posts: 1596
New South Wales

Re: .260 Load development pt1

Post by Apollo » 19 Sep 2017, 1:28 pm

Gamerancher wrote:Nice mirage in the video, we have a saying in BPCR silhouette, "never shoot in a boiling mirage". Just sayin'.


Same applies for Benchrest Target and cross fingers it changes within the 7 minute time slot.

That's pretty mild mirage in the video.
Apollo
Warrant Officer C1
Warrant Officer C1
 
Posts: 1327
New South Wales

Re: .260 Load development pt1

Post by Joom » 19 Sep 2017, 2:06 pm

Elmer wrote:I also work in Laboratories so I do a lot of weighing with scales that measure to 10,000th of a gram


How would work feel about you setting up a little reloading bench in the corner? :mrgreen:
Remington 700 and... Who needs another rifle?
User avatar
Joom
Lance Corporal
Lance Corporal
 
Posts: 101
Queensland

Re: .260 Load development pt1

Post by Gamerancher » 19 Sep 2017, 3:36 pm

Yeah it is Apollo, but it is still there and boiling. If I was load testing to see what shoots the best out of a rifle, I'd be looking for better conditions. There will be some indications of what the potential is but on watching the video carefully, you can see the elevation of the shots moving with the mirage. Don't know, wasn't there to see what Elmer could see. The man certainly can shoot, his videos are testimony to that. Not a criticism, just an observation. :thumbsup:
User avatar
Gamerancher
Sergeant Major
Sergeant Major
 
Posts: 1596
New South Wales


Back to top
 
Return to Reloading ammunition