.260 OCW Results...Thoughts?

[dustingaunder]

43-45.5gr of H4350. 140 ELDM. 100 yards. 45 and 45.5 started to show ejector swipe. 44.5 primers and case head looked perfect. The 45gr Load put two in the top hole and I think the low shot was me but I only had 3 of each so no do overs. All of these shots seem like they would have been in one group so I don’t know what to think. I’d previously done this starting lower and ending at 44. The node really started at 43 and was still shooting at 44. I wanted to see where it ended so I ran through the node again with this test. Any advice is appreciated.

I think I’m going to tune around 89gr for my 338 lapua test on the same target. 91.3 and 92 had started to show good ejector swipe and the primers were flowing a lot. I loaded up 92.8 but was afraid I’d pierce the primers. I’m thinking there’s another node starting there but I can’t get there with this chamber. 300gr Hybrid.

 

[pbatesaz]

I like 43 to 43.5. Both live on the baseline and slightly left of the vertical. It’s hard not to like that group at 44.5 though. For the 338 I like 88.3 to 89. You could try shooting at 200 tp make the differences stand out more. Hey my advice is worth what you just paid for it. Got any chrono data?

 

[Deleted member 10043]

Overlay that image on Google Earth and go down to eye level at the measured distance and use the zoom function to determine the ground from the shooter to the target is perfectly flat.

 

[dustingaunder]

Overlay that image on Google Earth and go down to eye level at the measured distance and use the zoom function to determine the ground from the shooter to the target is perfectly flat.

I’m not sure what you’re asking me to do but the range I shoot at is perfectly flat to 100 yards.

 

[Deleted member 10043]

No problem. You have it under control then.

 

[dustingaunder]

I dug into my notes and the .260 loads are 43.5, 43.8, 44.1, 44.4, 44.7, 45 gr. I was going off memory on the .5gr increments. 43.7 is the load I settled on last time. I’ve had it out to 1k with great results. Just really looking for more velocity. Rifle is a 20” factory Tikka. Come up to 1000 is 9.5 mils.

 

[Deleted member 10043]

44.5

 

[TxWelder35]

Do you have any velocity numbers by chance?

 

[dustingaunder]

I’m definitely gonna try that one at 600 and 1000 to see if it shoots like that at distance.

 

[dustingaunder]

Do you have any velocity numbers by chance?

No, sorry. I normally look at the paper when doing this then chrono later when tuning.

 

[TxWelder35]

No, sorry. I normally look at the paper when doing this then chrono later when tuning.

Gotcha, just curious. Powder load just seems really high. I was at 2900 FPS @41.7 grains h4350 with a 136gr scenar and seeing ejecter marks

 

[dustingaunder]

New lapua brass and 210M primers. 2.900 COL.

I’m assuming these 260 Tikkas are slow like the 6.5CMs. I know a lot of guys run around 44 gr with the 140s but then I see others around 41-42. Guess it just depends on the barrel. I’d rather get 2900 out of 41.7 than have to run 44.5.

 

[TxWelder35]

New lapua brass and 210M primers. 2.900 COL.

I’m assuming these 260 Tikkas are slow like the 6.5CMs. I know a lot of guys run around 44 gr with the 140s but then I see others around 41-42. Guess it just depends on the barrel. I’d rather get 2900 out of 41.7 than have to run 44.5.

Crazy how different barrels respond to different loads so drastically. 45 grains in my gun would be downright dangerous.

I was at 2.888 COL with a cci br2 LRP in once fired lapua brass

 

[dustingaunder]

My 338 topped out at around 90g of h1000 and a lot of people love 92gr with the 300 Hybrid.

 

[Steel head]

Crazy how different barrels respond to different loads so drastically. 45 grains in my gun would be downright dangerous.

I was at 2.888 COL with a cci br2 LRP in once fired lapua brass

My 260 with roomy Winchester brass and 2.94 oal wouldn’t take 45 grains of H4350.
Last barrel wouldn’t either.

 

[dustingaunder]

I took the 44.4 load and my 43.7 load out to 600 this morning. Good conditions with little to no wind.

I yanked one of the 44.4gr loads. 4 reliable shots went into this group.

The five 43.7 went into this group that landed on top of the 44.4gr group.

All 9 shots measured together.