Sierra 88 TMK Load Data

[bigunit]

Did some fire forming for 22-250 ai from regular 22-250 rem brass. 39.5 gr n555 and cci200. Really happy with the consistency and had a very low sd for fire forming. Averaged 3080fps.

 

[Schmo]

Did some fire forming for 22-250 ai from regular 22-250 rem brass. 39.5 gr n555 and cci200. Really happy with the consistency and had a very low sd for fire forming. Averaged 3080fps.
View attachment 1062416

I suppose it’ll work

 

[Deadspace]

16” factory tikka barrel with a TBAC ultra 9
24 grains of XBR
New Lapua brass
205MAR primers
2.46 OAL jumping .02
2600 FPS on average over 30 rounds.

The bottom left 10 shot group was .75” then made some zero adjustments on paper then verified drops on C zone sized steel IPSC targets out to 600. I need to double check those drops on paper but pretty happy that these things stabilize with the 1/8 twist. Basically zero load development too. Never messed with other seating depths. I tried 23 grains and was getting 2500FPS with 1” ten shot groups and tried two rounds with 25 grains getting 2700 fps but had some heavy bolt lift. Side note, the more I shoot the fixed six the more I like it.

 

[sierracharlie338]

Did some fire forming for 22-250 ai from regular 22-250 rem brass. 39.5 gr n555 and cci200. Really happy with the consistency and had a very low sd for fire forming. Averaged 3080fps.

Man fireforming is such a hassle and you don’t get useful data out of fireforming loads…..

Said someone who has never actually done it.

Nice shooting

 

[Big_wals]

Got some 88s in the mail today and shot a bit before supper. Tikka 16” .223, factory barrel.

23.0 XBR 2553 fps

23.4 XBR 2609 fps

Lake city brass, CCI 450 primers. Loaded to 2.458 oal, .025 off the lands. Only shot 5 rounds of each, one group was right at an inch, the other was barely over. Slightly cratered primers with both loads, no ejector marks or heavy bolt lift.

 

[bigunit]

Man fireforming is such a hassle and you don’t get useful data out of fireforming loads…..

Said someone who has never actually done it.

Nice shooting

I used to use cheaper components and faster powder for fire forming but now I pretty much just load up the components I want to shoot and have at er. I now have about 400 fireformed 22-250 ai brass so that will out last this barrel if I don't step on them too hard.