Are flat base bullets ok for mid range ?

[Road_Clam]

So thus far been enjoying shooting at my 600 yd range, and my skills seem to be slowly improving. I've been doing some research and would like to take my K98 8mm Mauser out to 600 yds. Thus far have only tested IMR 4350 and 198gr PPU FMJBT bullets and did not have very good accuracy. The best I got was about 3.5 MOA so I'm not confident taking this combo out too 600. The velocities were maxed out around 2240 fps , and that risks transonic instability at 600 yds. I would like to try something in the 175 gr but seems slim choices as far as BT target bullets. Was wondering if any of you had good success taking flat base hunting bullets out to midrange distances ?

 

[watercam]

Re: Are flat back bullets ok for mid range ?

I was under the impression that Sierra had a Matchking in 8mm.

https://www.sierrabullets.com/store/product.cfm/sn/2415/323-dia-8mm-200-gr-HPBT-MatchKing

Still heavy but should hold its velocity better. What pressure signs were you getting? Hodgdon shows H4350 with starting loads at 2250-ish and 2500+ max.

 

[Road_Clam]

Re: Are flat back bullets ok for mid range ?

I was under the impression that Sierra had a Matchking in 8mm.

https://www.sierrabullets.com/store/product.cfm/sn/2415/323-dia-8mm-200-gr-HPBT-MatchKing

Still heavy but should hold its velocity better. What pressure signs were you getting? Hodgdon shows H4350 with starting loads at 2250-ish and 2500+ max.

MTM, when I tested the PPU 198's I started getting a sticky bolt extraction and I got a bit concerned about elevated pressures. The primers looked fine. However I'm using resized -06 casings and maybe it's possible I need to skim cut the OD of the necks again. I think I might go back and test the 4350 right up to max suggested loads. I still have the bullets I just didn't finish shooting all the loads.

 

[watercam]

What about necking 7x57 brass up to 8mm? At least the other dimensions will be the same.