First Ever Load Development Help

[YotaEer]

So the below pictures and chicken scratch reference my first 27 rounds I’ve ever reloaded. Not gonna lie, I was very nervous that I was going to blow up but they all seemed to work well.

With the current shortage of components, I’d like to keep additional load development to a minimum and looking for experienced reloaders take on my data.

Specs: Tikka 6.5 CM, 20” PVA barrel, silencer co omega, once fired hornady brass, Winchester LRP, H4350 and 140 ELD.

My best group came from factory 140 ELD followed by 40.3 grains of H4350 (first pic). My next best groups came from 42.4 grains and 41.2, respectively (second pic). The final picture shows my chicken scratch of velocity, SD and ES.

41.2 grains had the second lowest SD and ES, behind 41.5, but 41.5 shot poorly. My gut says stick with 41.2 since I get the improved velocity and consistency over factory with only a minor hit to accuracy. However I’m also thinking of trying out the 42.4 again due to its grouping, despite the lower consistency and some minor pressure signs.

Long story short, stick with the 41.2? Thoughts?

 

[ScottPriestley]

Thats pretty awesome - Id say stick with the 41.5 and consider seating depth as the only other variable.

 

[YotaEer]

Thats pretty awesome - Id say stick with the 41.5 and consider seating depth as the only other variable.

So you recommend going with 41.5 instead of the 41.2 and varying depths?

 

[pell1203]

Just as a point of reference...

With that powder, brass, and bullet combination there are well known nodes in the 41.3-41.5 range at ~2700 fps and a higher velocity node in the 42.3-42.6 range at ~2780 fps. These MVs are out of a PVA 24” barrel on a 6.5 Creedmoor RPR.

I’d try jumping them about 0.030” for a baseline and adjust from there. Good luck!

 

[308sako]

With your component combination, and a few other unmentioned factors; (cartridge over all length etc,) I would say simply that the above concept of .030" or my suggestion of .020" "Jump' would then open another phase of testing for you. However the 41.2, and 42.5 grain charge weights should be your focus with he seating depth/cartridge overall length. My guess is that the 42.5 grain load in the shorter barrel will be best for you.

 

[Dthomas3523]

Purely based on data provided (assuming it’s good data and good loading methods):

Go with 41.3 or 41.4, do a seating depth test and done.