120gr. Sierra Tipped Game King, Winchester Staball Match

[tdbru]

used 31.0gr. of WSM, RP 7 1/2 primer, Starline cases. Seated the 120 STGK as far out as my elander magazines would allow.

20" AR. Faxon Gunner barrel. avg mv = 2485 fps. Sierra lists 2600 fps in a 24" tube.

22" Ruger American Gen 2 Predator. avg mv = 2487 fps.

pressures looked less than Hornady American Gunner factory ammo based upon fired primer radius, for what that's worth.

I may have two "slow" barrels, however, Hornady listed their American Gunner ammo (123gr. BTHP) at 2590fps (no barrel length given) and out of my 20" faxon gunner tube it averages 2467 fps.

If same MV = same pressure, which I doubt is exact, then these hand loads appear to be in the same pressure area as the Hornady American Gunner factory ammo as both are within 18 fps of each other in the 20" faxon gunner barrel.

I was mainly looking for MV and pressure signs with the few loads I fired in each rifle. Not enough to state a given group size. Next step is to load up enough of them to establish a group size in my rifles. I'd estimate both to be in the 1MOA - 1.25 MOA range but the sample size is too small to state that with any confidence.
best regards,
tdbru

[grayfox]

I'm hoping that shoots well for you. Been looking at the staball match but have other powders so have not bought any yet.
In a general sense, max pressure is close to proportional to MV for equal barrel lengths... but it's more related to the avg pressure for the length of the barrel (ie, area under the P-Length curve). Higher peaks and narrower, like H335 or other fast powders, will not equate to MVs of lower peaks and broader, like CFE or lever if you just look at the peak. If WSM is close to varget, but a ball powder, that means it could be useful indeed.
I don't know if I have a GRT entry for staball match, if I do I will compare it with some others.
Looks right about like the MV's for Ar comp and H4895 for me in my 20", although higher grain weights. My 20" I get 2490-2510 for those 2 powders but more in the 27.4-28.0 range.

[tdbru]

I am trying Winchester Staball Match since many other "favorite" powders are unobtainium. Many of the extreme powders that Hodgdon resells are from ADI (Australia) and I haven't seen any H4895, which I like for both the burn rate and the temp stability, for over 5 years. 8208XBR, also from ADI, was absent for years as well. I concour that staball match is on the slow side of useable, but it's at least available since it's made domestically. Many of the IMR powders (made in Canada) were also gone from the shelves for years. and let's not even get started about Alliants (Bofors, Sweden) Reloader series. Since both the CFE and StaBall series of powders are made by Olin in Florida, and are available, I am slowly trying to transition all my loads over to those powders since I dislike having the powders I reload with being unavailable. Winchester seems to have stepped up to fill the void and support us reloaders when we're 2nd (or 3rd) fiddle to other powder manufacturers. So they'll get my business.
best to you,
tdbru

[tdbru]

forgot to add, Sierra indicated to me that they designed the 120gr. Tipped Game King expressly for the 6.5 Grendel so it should be a good hunting bullet for us.
-tdbru

[grayfox]

10-4. There was a brief window for h4895 and Xbr last week or 2 or so... but only for a day or so. I got a couple lbs each from natchez, couple dollars cheaper than the hodgdon site, but at same time as hodgdon. You might also consider AR comp, which is close to the Xbr numbers in the 120-129 class, and I'm finding benchmark works for some of my loads vice h4895 (thinking mostly for the 308, since I have several for the grr already). But it might work for the 120 tgk also.
Go ahead and put in alerts for these on ammo seek, and also at the vendors (natchez, brownells, etc) to alert you when they do come in. Thinking they are being run in a batch and not continuously...
But I definitely feel the same, why do loads if you can't get the powders.
Ain't life grand...

[grayfox]

I have a load for my 20" in 120 tgk, 28.2 Xbr, 2512 fps, translates load estimate for benchmark, 27.6 grs, 2484... same node ~ 2490-ish.
And my lgs (10 mins away - terrible!! ) has both Ar comp and benchmark on the shelf. Bmrk is better $$.

[grayfox]

Powder valley has 8208 xbr, 1# bottles, in stock right now...........

[tdbru]

Thanks Grayfox. I am a little hesitant to develop a good load with xbr in case it goes away for another 5 years or so. I have not seen 8208 XBR or H4895 on any of the local shelves here in 5 years. Looks like you have to order those, and be quick about it when they show up.
thanks again Grayfox.
-tdbru