77 TMK 8208 XBR load dev

[sveltri]

Did some testing today to see if I could find a good load. Components used: Tikka Super Varmint 24”, Starline 223 3x fired, rem 7.5, 8208, 77 tmk. Warmed up the gun with some factory 73gn match, then 23, 23.3, 23.6, 23.9, 24.2. Velocity #’s on the last group were Ave. 2888 ES 25.3 SD 8.7. Loaded the remaining brass at 24.2. 5 shot groups.

 

[swavescatter]

What neck tension are you using? I picked up about 50fps using a light crimp because I used a neck bushing that was slightly too big. Never saw this accuracy though.

 

[sveltri]

Not a bushing die, just a standard Hornady resizing die.

 

[doc holiday13]

I'd bet you'd get some good traction on this if you posted in the reloading section

 

[riversidejeep]

I should sell about 15 rifles that sit in the safe and get a Super Varmint .223, I've wanted one since the came out because they shoot so well and you have proven it again!

 

[Pharmseller]

You’re a grain over max, no pressure signs? Is 8208 temp stable?

I have a couple thousand 77 TMK but I got started on 75 ELDM and Benchmark but now that 8208 is hitting the shelves I’m getting curious.




P

 

[BringBackThe80s]

Nice! I'm testing 8208 and 77 tmks myself, but out of an AR with 20" bull barrel. Hoping to see some good results.

 

[rifletuner]

I have tried 8208 XBR in 223s with heavy for calibre bullets a few times, but never get particularly good velocities. Maybe it works better in shorter barrels rifles or semi-autos, since I have only tried it in bolt actions with 24-26 inch barrels. But for me, H4895 and Varget have been much better options.

 

[sveltri]

You’re a grain over max, no pressure signs? Is 8208 temp stable?

I have a couple thousand 77 TMK but I got started on 75 ELDM and Benchmark but now that 8208 is hitting the shelves I’m getting curious.




P

No detectable pressure signs. Bolt lift was normal, no ejector swipes, no primer punctures. I'll look again at the primers and see if I had any flattening.

 

[Jesse Jaymes]

This is my Go To combo in 223 AI. I very much love this powder. Most suggest TAC. I think XBR is quite a bit more FPS than max charge of TAC. My loads are over yours, but I am AI'd.

 

[Wrench]

My 223ai runs 24.3 8208xbr under a 77tmk at 2850.....and shoots about like yours.

 

[Lawnboi]

That’s a lot of xbr in a straight 223