bullet seating question

[dan06]

Ok my new 6.5x284 is ready to go and I tried some listed loads for it with H4831and berger 130 gr vld's. It groups very well as my first 3-3 shot groups averaged were a little under .5" at 100 yards I got the crono out and the velocity wasn't what I expected at right around 2650fps. I'm going to use this as my long range out to 4-500 yard hunting rifle so I was looking for a little more velocity. I next tried a couple of different powders and got safely up to 3000fps but the groups opened up to a little more than MOA. with very consistant velocity.

My question is should the same seating depth work with these loads if it worked once or will I have to start over on experimenting with seating depth if I change loads.

 

[necchi]

I'm not real good with technical answers, but in my experiance changeing seating position once the powder charge has been found CAN be an advantage to tightening up the groups.

Then another small charge change CAN be a futher improvment after that seating depth is found.

That's the neat thing we as loaders can do, we can keep tweeking variables till the best results are found.

In other words, Yes. But it's not really starting over it's a continual quest for best ;D

 

[CdnHotshot]

Just a thought - IMR4831 will produce from 85-95 fps more velocity as compared H4831SC with same powder weights. My accuracy improved with IMR4831 as the velocity and pressure increased.
Hope you might consider this a try.

 

[Larryh128]

IMR 4831 would be faster because it's a faster burn rate than H4831. The 2 aren't interchangeable for loading data.

 

[mikecr]

will I have to start over on experimenting with seating depth if I change loads

What seating depth tests have you done so far?

I find best seating depth first, with any powder(during brass fireforming). Then move onward with incremental loading/ladder with fully formed cases -sized MY way.
Once my charge is producing well, I revisit seating with +/- tweaks to center it's window of performance. I'm not tuning at this point, that's not what seating does. Just lookin at what condition my condition is in.
I can change powders without going back to seating. But if I change bullets, I start all over.

 

[Shootinstick]

Suggest you try switching to a slower different powder such as Reloader 22 or VV N160. If you move up to 140 grain bullets, I use VV N165.